AnyCloud Bluetooth Advertising Scanner (Part 10)

Summary

We have finally reached the end of the AnyCloud Bluetooth Advertising Scanner.  In this article I will add the ability to sort the database.  In addition I will add the ability to purge a device.  And finally, truly finally, a bit of commentary.

Story

I originally built this program to help me learn about the AnyCloud Bluetooth SDK.  Well, originally I built this functionality to try to find and talk to a specific device (in an upcoming series).  The problem is that there are so many devices at my house that are blasting out so much data it is hard to see what I am looking for.  What I realized would help is add the ability to sort the devices from newest to oldest.  In addition I noticed that occasionally my database would fill up… and it would be nice to purge out old entries.  So that is what we are going to do.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Fix the Database Data Structure

You might remember that the database was built as an array of structures.  This mean that any moving around of the data would be a require a replacement of the whole structure.

static adb_adv_t adb_database[ADB_MAX_SIZE];

To fix this problem I moved the database to a an array of pointers.

static adb_adv_t *adb_database[ADB_MAX_SIZE];

To support this, when I see a new device I malloc a block of memory to hold the actual structure.

    // If it is NOT found && you have room
    if(entry == -1)
    {
        adb_database[adb_db_count] = malloc(sizeof(adb_adv_t));

Then I had to fix all of the references to the structure.  And there were a bunch (actually 43 of them).  But the replacement was pretty simple

adb_database[…].xxx is replaced by adb_database[…]-> …. here are the three different cases

case 1: adb_database[adb_db_count].

case 2: adb_database[entry].

case 1: adb_database[i].

That was actually way less painful that I thought it was going to be.  Probably what would actually be best is a library of these data structures with an API that would not have changed when the key changed, but that I suppose, is for another day.

Add Two New Commands

Now I add the sort and purge commands to my command list.

typedef enum {
    ADB_ADD,
    ADB_PRINT_RAW,
    ADB_PRINT_DECODE,
    ADB_WATCH,
    ADB_ERASE,
    ADB_RECORD,
    ADB_FILTER,
    ADB_SORT,
    ADB_PURGE,
} adb_cmd_t;

Create the Sort Functionality

To sort, I will use the c-standard library function qsort.  It requires a function that compares two entries a/b and returns

  1. a negative number of a<b
  2. 0 if a=b
  3. a positive number if a>b

Here is the function.  Hey Hassane you like those pointers?

static int adb_sort_cmpfunc(const void * a, const void * b) 
{
    adb_adv_t *p1 = *((adb_adv_t **)a);
    adb_adv_t *p2 = *((adb_adv_t **)b);
        
    return p2->lastSeen - p1->lastSeen;
}

The sort is actually really simple now.  Just a call to sort (then I decided to print out the table)

                case ADB_SORT:
                    qsort(adb_database, adb_db_count, sizeof(adb_adv_t *), adb_sort_cmpfunc);
                    adb_db_print(ADB_PRINT_METHOD_BYTES,true,-1);
                break;

Now instead of this….

I get this…

Create the Purge Functionality

The purge function needs to do two things

  1. Free all of the memory from an entry
  2. Move the pointers so that the “purged” entry is gone.

First I erase all of the data in the linked list with the adb_eraseEntry function.

Then I free the head of the list

Then I free the actual structure

Then I move all of the pointers to squeeze the able.

static void adb_purgeEntry(int entry)
{

    adb_eraseEntry(entry);
    free(adb_database[entry]->list);
    free(adb_database[entry]->result);
    free(adb_database[entry]);
    adb_db_count -= 1;
    for(int i=entry;i<adb_db_count;i++)
    {
        adb_database[i] = adb_database[i+1];
    }
}

And you need to add the actual command.

                case ADB_PURGE:
                    if((int)msg.data0<0 || (int)msg.data0>=adb_db_count)
                    {
                        printf("Purge error %d\n",(int)msg.data0);
                        break;
                    }   
                    adb_purgeEntry((int)msg.data0);
                break;

The End & Commentary

I would like to add and maybe will one day:

  1. A connect function with a GATT browser
  2. A smarter way to deal with the fact that device change addresses

Finally a couple of comments about this

  1. You might notice that I don’t check very many possible errors.  I do this in the interest of simpler to read code.  This is a tradeoff that I make for “teaching” code.  I hope that you understand that if you want to do something like this in a real product that you need to be much more careful.
  2. I don’t have unit testing.  This falls into the same category as the error checking.  Really this is a bad idea as code without unit testing is obsolete the second it comes out of your fingers.  But, it is easier to read.
  3. I don’t have many comments.  This is something that my colleagues bitch about all of the time with me.  And I know that it must be a personality defect.
  4. I use malloc/free all over the place.  This is a religious war.  You can make a static allocation scheme, but it would be really complicated in this case.  I personally think that the tradeoff of using a battle worn and tested malloc/free is totally worthwhile against the complexity of custom static memory allocation schemes.

AnyCloud Bluetooth Advertising Scanner (Part 9)

Summary

In this series of articles I am building a Bluetooth Low Energy Scanner using the Cypress/Infineon AnyCloud SDK running on a PSoC 6 and CYW43xxx.  In Part 9, I will fix a memory leak, add packet age, and improve the printing.

Story

You might be starting to wonder if this series is ever going to end.  Well, this article and one more.  That is it.

This morning as I was looking at the serial console window I noticed that I had hit the limit of device in the buffer,  OK.  But that it had also crashed, gone, bye bye, so long … the long dark road.  That needs fixing.

I also was curious when I looked at the output, how long ago I had seen the packets/devices.  So I decided that having “age” in the database made sense.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Fix the Memory Leak

I noticed that a while after I started getting the message “ADV Table Max Size” that things would crash.  But Why?  The answer is a memory leak – go figure. I originally thought when I get a new device I would just overwrite the last entry in the table.  But, when I overwrote the adb_database[adb_db_count]. record with a new scan_result and a new list, I left memory that was previously allocated, here is the code:

    if(entry == -1)
    {
        adb_database[adb_db_count].result = scan_result;
        adb_database[adb_db_count].listCount = 1;
        adb_database[adb_db_count].record = false;
        adb_database[adb_db_count].filter = true;
        adb_database[adb_db_count].numSeen = 1;

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = 0;
        current->data = data;
        current->count = 1;

        adb_database[adb_db_count].list = current;

        adb_db_count = adb_db_count + 1;
        if(adb_db_count == ADB_MAX_SIZE)
        {
            printf("ADV Table Max Size\n");
            adb_db_count = adb_db_count - 1;
        }
        else
        {    
            adb_db_print(ADB_PRINT_METHOD_BYTES,false,adb_db_count-1);
        }
    }

A cheap fix is to just stop making new entries when the database runs out of room.

    // If there is a new entry and you ran out of space
    if(entry == -1 && adb_db_count >= ADB_MAX_SIZE)
    {
        free(scan_result);
        free(data);
        return;
    }

Add Age

As I mentioned earlier I wanted to keep track of

  1. The last time I had seen a device
  2. When I saw that specific advertising packet

The FreeRTOS has a free running millisecond counter that starts a 0 and counts up to 2^32.  A really cheap way to keep track of time is just to use this counter. To do this the first step is add the time to the database.  Both in the device record and the packet record.

typedef struct {
    uint8_t *data;
    int count;
    TickType_t lastSeen;
    struct adb_adv_data_t *next;
} adb_adv_data_t;

typedef struct {
    wiced_bt_ble_scan_results_t *result;
    bool record;
    bool filter;
    int numSeen;
    int listCount;
    TickType_t lastSeen;
    adb_adv_data_t *list;
} adb_adv_t ;

Update the Printing

I am going to make the output look like this with a new column representing the seconds since I heard the packet.  In the picture below you can see that I heard 00 at 0.0 seconds ago…  Then you can see that I had a recording of device 5 where I have a bunch of packets that I heard back into time.

To do this I just add a time calculation like this:

static void adb_db_printEntry(adb_print_method_t method, int entry, adb_adv_data_t *adv_data)
{
    float time = ((float)xTaskGetTickCount() - (float)(adv_data->lastSeen))/1000;

    printf("%c%c%02d %05d %03d %6.1f ",adb_database[entry].watch?'W':' ',
    adb_database[entry].filter?'F':' ',
    entry,adb_database[entry].numSeen,adb_database[entry].listCount,
    time);

Fix up the Add

The next thing that I need to do is make the “add” function add the time.  The problem is that this function has gotten totally totally out of control.  It turns out that there are x different possibilities

  1. Ignore the packet (because the table is full)
  2. Add a new device & packet
  3. Update the head of the list with a new packet
  4. Insert a new packet at the head of the list
  5. If you are filtering update a duplicated packet count

The code for these branches all looked somewhat similar.  But, which branch to take depended on

  1. If you were “watching” that device
  2. If you were “filtering” that device
  3. If you were “recording”
  4. If you had seen that packet before (aka it was found)

I ended up making a truth table:

Watch Filter Recording Found Action
0 0 0 0 update the head
0 0 0 1 update the head
0 0 1 0 update the head
0 0 1 1 update the head
0 1 0 0 update the head
0 1 0 1 update the head
0 1 1 0 update the head
0 1 1 1 update the head
1 0 0 0 update the head
1 0 0 1 update the head
1 0 1 0 insert at the head
1 0 1 1 insert at the head
1 1 0 0 update the head
1 1 0 1 update the found
1 1 1 0 insert at the head
1 1 1 1 update the found

The case where you

  1. Had no room
  2. Saw a new device

Look like this:

static void adb_db_add(wiced_bt_ble_scan_results_t *scan_result,uint8_t *data)
{

    TickType_t timeSeen = xTaskGetTickCount();

    int entry = adb_db_find(&scan_result->remote_bd_addr);

    // If there is a new entry and you ran out of space
    if(entry == -1 && adb_db_count >= ADB_MAX_SIZE)
    {
        free(scan_result);
        free(data);
        return;
    }
    
    // If it is NOT found && you have room
    if(entry == -1)
    {
        adb_database[adb_db_count] = malloc(sizeof(adb_adv_t));
        adb_database[adb_db_count]->result = scan_result;
        adb_database[adb_db_count]->listCount = 1;
        adb_database[adb_db_count]->watch = false;
        adb_database[adb_db_count]->filter = true;
        adb_database[adb_db_count]->numSeen = 1;
        adb_database[adb_db_count]->lastSeen = timeSeen;

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = 0;
        current->data = data;
        current->numSeen = 1;
        current->lastSeen = timeSeen;

        adb_database[adb_db_count]->list = current;

        adb_db_count = adb_db_count + 1;    
        adb_db_print(ADB_PRINT_METHOD_BYTES,false,adb_db_count-1);

        return; 
    }

At this point in the code you know that you have seen this device before.  If you are filtering you should look in the linked list to see if you can find the specific packet (lines 1-15).

If you look at the truth table above you will see three cases where you should insert at the head of this list.  Those cases are identified with the sprawling if on lines 17-21).  Once you identify that scenario you do the needful.

    adb_adv_data_t *updateItem=0; 

    if(adb_database[entry].filter) // if filtering is on.
    {
        int len = btutil_adv_len(data); // ARH maybe a bug here
        
        for(adb_adv_data_t *list = adb_database[entry].list;list;list = (adb_adv_data_t *)list->next)
        {
            if(memcmp(list->data,data,len) == 0) // Found the data
            {
                updateItem = list;
                break;
            }
        }
    }

    // insert at the head
    if( (adb_database[entry].watch && !adb_database[entry].filter && adb_recording && !updateItem) ||
        (adb_database[entry].watch && !adb_database[entry].filter && adb_recording && updateItem) ||
        (adb_database[entry].watch && adb_database[entry].filter && adb_recording && !updateItem)
    )
    {
        adb_adv_data_t *updateItem = malloc(sizeof(adb_adv_data_t)); // make new data
        updateItem->next = (struct adb_adv_data_t *)adb_database[entry].list;
        updateItem->numSeen = 1;
        updateItem->data = data;
        updateItem->lastSeen = timeSeen;

        adb_database[entry].list = updateItem;
        adb_database[entry].numSeen += 1;
        adb_database[entry].lastSeen = timeSeen;
        adb_database[entry].listCount += 1;
        free(scan_result);
        
        adb_db_print(ADB_PRINT_METHOD_BYTES,false,entry);


        adb_recording_count += 1;
        if(adb_recording_count == ADB_RECORD_MAX)
        {
            adb_recording = false;
            printf("Recording buffer full\n");
        }
        return;
    }

The final case happens when you are just going to update a found packet.

    if(updateItem == 0)
        updateItem = adb_database[entry].list;


    adb_database[entry].numSeen += 1;
    adb_database[entry].lastSeen = timeSeen;

    updateItem->lastSeen = timeSeen;

    int len = btutil_adv_len(data); // ARH maybe a bug here
    if(memcmp(updateItem->data,data,len) == 0)
    {
        updateItem->numSeen += 1;
    }
    else
    {
        updateItem->numSeen = 1;   
    }

    free(updateItem->data);
    updateItem->data = data;
    free(scan_result);

}

In the next article I will add

  1. Sort
  2. Purge

Then I will call it  a day.

AnyCloud Bluetooth Advertising Scanner (Part 8)

Summary

In this series of articles I am building a Bluetooth Low Energy Scanner using the Cypress/Infineon AnyCloud SDK running on a PSoC 6 and CYW43xxx.  In Part 8 I will turn on the ability to filter duplicate advertising packets.

Story

In the previous article I added the ability to record advertising packets.  The problem is, of course, that many devices are blasting out advertising packets, which will quickly overwhelm you.  I suppose more importantly it will overwhelm the packet buffer.  Most of the device are just advertising their presence, so they send the same data over and over.  Some devices alternate between a small number of different advertising packets, e.g. an iBeacon then and Eddystone beacon.

The way that the filter will work is that I will update the “add” function to search through all of the packets that device has launched, then if I have seen the packet before (Ill use a memcmp) then I will just keep a count of how many times I have see that packet.

The other thing that needs to happen is for me to add a “filter” command so that I can turn on packet filtering on a device by device basis.

And I need to fix the printing to use the new filtered packet database.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Update the Data Structures

In order to do the filters, and keep track of the data I will add

  1. A “count” field to the packet data structure
  2. A “filter” boolean field to the device data structure.
typedef struct {
    uint8_t *data;
    int count;
    struct adb_adv_data_t *next;
} adb_adv_data_t;

typedef struct {
    wiced_bt_ble_scan_results_t *result;
    bool record;
    bool filter;
    int numSeen;
    int listCount;
    adb_adv_data_t *list;
} adb_adv_t ;

Update the Add Function

In the function “static void adb_db_add(wiced_bt_ble_scan_results_t *scan_result,uint8_t *data)” which is called every time I see a new advertising packet I will need to handle four different cases:

  1. The first time you see a device
  2. A device you have seen AND you are recording AND have the filtering turned on
  3. A device you are recording but not filtering
  4. A device you have seen, but are not recording or filter.

In the first case, a device you haven’t seen before, you need to

  1. Automatically turn on the filtering
  2. Initialize the counts to 1
  3. Do the other initialization (as before)
    // If it is NOT found
    if(entry == -1)
    {
        adb_database[adb_db_count].result = scan_result;
        adb_database[adb_db_count].listCount = 1;
        adb_database[adb_db_count].record = false;
        adb_database[adb_db_count].filter = true;
        adb_database[adb_db_count].numSeen = 1;

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = 0;
        current->data = data;
        current->count = 1;

In the case where you have

  1. See the device before
  2. You have room in the record buffer
  3. And you are in record mode

You will then decide if you are filtering.

Then you will iterate through all of the packets and compare the data to the data you just received.  If there is a match then you update the count, free the duplicate data and return.

    else if(adb_database[entry].record && adb_recording_count<ADB_RECORD_MAX && adb_recording)
    {
        adb_database[entry].numSeen += 1;

        if(adb_database[entry].filter) // if filtering is on.
        {
            int len = btutil_adv_len(data); 
            for(adb_adv_data_t *list = adb_database[entry].list;list;list = (adb_adv_data_t *)list->next)
            {
                if(memcmp(list->data,data,len) == 0) // Found the data
                {
                    list->count += 1;
                    printf("Count = %d\n",list->count);
                    free(data);
                    free(scan_result);
                    return;
                }
            }
        }

If you have not see the data before, then you need to add it to the linked list.

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = (struct adb_adv_data_t *)adb_database[entry].list;
        current->data = data;
        current->count = 1;

If you are not recording and not filtering, just increment counts.

    else
    {
        adb_database[entry].numSeen += 1;
        adb_database[entry].list->count += 1;

Add a “filter” Command

I want the ability for a user to “filter all” or “filter clear” or “filter #” – just like we did with watch.  So, add the #defines and new function to advDatabase.h

#define ADB_FILTER_ALL -1
#define ADB_FILTER_CLEAR -2
void adb_filter(int entry);

Then add the new filter command in advDatabase.c

typedef enum {
    ADB_ADD,
    ADB_PRINT_RAW,
    ADB_PRINT_DECODE,
    ADB_WATCH,
    ADB_ERASE,
    ADB_RECORD,
    ADB_FILTER,
} adb_cmd_t;

I will use the adb_queueCmd function that I created in the last article.

inline void adb_filter(int entry) { adb_queueCmd(ADB_FILTER,(void*)entry,(void *)0); }

The filter command has three cases

  1. All – turn the bool for all on
  2. Clear – turn the bool for all off
  3. Just a specific number – toggle that specific number
static void adb_db_filter(int entry)
{
    if(entry == ADB_FILTER_ALL)
    {
        for(int i=0;i<adb_db_count;i++)
        {
            adb_database[i].filter = true;
        }
        return;
    }

    if(entry == ADB_FILTER_CLEAR)
    {
        for(int i=0;i<adb_db_count;i++)
        {
            adb_database[i].filter = false;
        }
        return;
    }

    if(entry > adb_db_count-1 || entry < ADB_WATCH_CLEAR)
    {
        printf("Record doesnt exist: %d\n",entry);
        return;      
    }
    adb_database[entry].filter = !adb_database[entry].filter; 

}

And you need to fix up the main command processor

                case ADB_FILTER:
                    adb_db_filter((int)msg.data0);
                break;

Finally add the command to the usrcmd.c

static int usrcmd_filter(int argc, char **argv)
{

    if(argc == 2 && !strcmp(argv[1],"all"))
    {
        adb_filter(ADB_FILTER_ALL); // all
        return 0;
    }


    if(argc == 2 && !strcmp(argv[1],"clear"))
    {
        adb_filter(ADB_FILTER_CLEAR);
        return 0;
    }

    if(argc == 2)
    {
        int i;
        sscanf(argv[1],"%d",&i);
        adb_filter(i);
        return 0;
    }

    return 0;
}

Fix the Printing

Now we nee to fix the printing.  I want to add an indicate of the filtering to the output.  Remember from the previous article I indicated “Watch” with a “*”.  When I looked at it, I decided that I should indicate filter with an “F” and watch with a “W”.  So I fix that.

        printf("%c%c%02d %05d %03d MAC: ",adb_database[i].record?'W':' ',
            adb_database[i].filter?'F':' ',
            i,adb_database[i].numSeen,adb_database[i].listCount);
        btutil_printBDaddress(adb_database[i].result->remote_bd_addr);
        switch(method)
        {

Then I test the “filter” command

Fix the Printing Part (2)

As I noodled on how to change the printing I decide that it would be nice to sometimes print out only one packet e.g. no history and sometimes print them all out e.g. history.  So, I add a new parameter to the function called “history”

static void adb_db_print(adb_print_method_t method,bool history,int entry)

As I looked at the printing code, I decided that it would be better to have a new function to print only one entry.  I suppose that I could have left the code inline, but I thought that intent was clearer.

static void adb_db_printEntry(adb_print_method_t method, int entry, adb_adv_data_t *adv_data)
{
    printf("%c%c%02d %05d %03d MAC: ",adb_database[entry].record?'W':' ',
    adb_database[entry].filter?'F':' ',
    entry,adb_database[entry].numSeen,adb_database[entry].listCount);
    btutil_printBDaddress(adb_database[entry].result->remote_bd_addr);

    switch(method)
    {
    
    case ADB_PRINT_METHOD_BYTES:
        printf(" Data: ");
        btutil_adv_printPacketBytes(adv_data->data);
    break;

    case ADB_PRINT_METHOD_DECODE:
        printf("\n");
        btutil_adv_printPacketDecode(adv_data->data);
    break;
    } 
    printf("\n");

}

With the new function in place I now need to update the print function to call the new entry function.  Printing the history is just a matter of iterating through the linked list.

static void adb_db_print(adb_print_method_t method,bool history,int entry)
{
    int start,end;
 
    if(entry < 0)
    {
        start = 0;
        end = adb_db_count;
    }
    else
    {
        start = entry;
        end = entry+1;
    }

    if(end>adb_db_count)
        end = adb_db_count; 

    for(int i=start;i<end;i++)
    {
        if(history) // then iterate through the linked list print all of the packets
        {
            for(adb_adv_data_t *list = adb_database[i].list;list;list = (adb_adv_data_t *)list->next)
            {
                adb_db_printEntry(method,i,list);    
            }
        }
        else // Just print the first packet in the list
            adb_db_printEntry(method,i,adb_database[i].list);
    }
}

Now, I need to update all of the calls to adb_db_print to have the new history parameter.  First, I made the decision that when you “print” from the command line that you are interested in the history.

                case ADB_PRINT_RAW:
                    adb_db_print(ADB_PRINT_METHOD_BYTES,true,(int)msg.data0);
                break;
                case ADB_PRINT_DECODE:
                    adb_db_print(ADB_PRINT_METHOD_DECODE,true,(int)msg.data0);
                break;

But when you are printing out the packet for a new device don’t print out the history

            adb_db_print(ADB_PRINT_METHOD_BYTES,false,adb_db_count-1);

Program and Test

After I program my development kit, I start by typing “watch all”.  Very quickly, at my house, you can see that a bunch of devices are discovered.  You can see that all of these have a “W” (meaning that I am watching them) and an “F” meaning they are filtering out duplicates.  Then I type “record” to turn on recording. After a minute I turn off recording then do the print you can see below.

A couple of things to notice.

  1. Device #4 (which I highlighted) appears to be sending out a pattern of alternating packets.  See that I have heard 3335 packets yet there are only two in the buffer
  2. You can see device 11 seems to be sending out 16 different packets.  Why?  I don’t know.

But we can “decode 11” to try to figure it out.  You can see that it is advertising manufactures specific data with Apple’s UUID which I happen to know is 0x004C.  But why?  I don’t know.

I really want to move onto a new series of articles… but there are two functions which I will add to the program.  Stay tuned for what they do.

AnyCloud Bluetooth Advertising Scanner (Part 7)

Summary

In this series of articles I am building a Bluetooth Low Energy Scanner using the Cypress/Infineon AnyCloud SDK running on a PSoC 6 and CYW43xxx.  In Part 7 I will add the ability to record BLE ADV packets.

Story

If you have been reading along, at this point we have built a BLE scanner that can see Bluetooth devices that are advertising.  My scanner has a command line and you can print out the most recent data.  Even better, we built a decoder that allows you to better understand the data.

Now I want to add the ability to record more than one advertising packet per device.  To that end I will add three commands:

  • watch – Mark a device as one that needs to have the advertising data recorded.  You can type “watch 12” or you can say “watch all” or you can say “watch clear”
  • record – Turn on recording of “watched” devices.  When you type record it will toggle the recording state between On and Off.
  • erase – clear the record buffer of all but the most recent packet.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Update the advDatabase Interface

The first thing I realized as I went to add a new command was that I was typing the exact same code over and over for the public interface.  The code looked like this:

void adb_watch(int entry)
{
    adb_cmdMsg_t msg;
    msg.cmd = ADB_WATCH;
    msg.data0 = (void *)entry;
    xQueueSend(adb_cmdQueue,&msg,0); // If the queue is full... oh well

}

So I created this:

static void adb_queueCmd(adb_cmd_t cmd,void *data0, void *data1)
{
    adb_cmdMsg_t msg;
    msg.cmd = cmd;
    msg.data0 = data0;
    msg.data1 = data1;
    xQueueSend(adb_cmdQueue,&msg,0); // If you loose an adv packet it is OK...
}

Then did this to eliminate the duplication.

inline void adb_addAdv(wiced_bt_ble_scan_results_t *scan_result,void *data) { adb_queueCmd(ADB_ADD,(void *)scan_result,(void *)data);}
inline void adb_print(int entry) { adb_queueCmd(ADB_PRINT_RAW,(void *)entry,(void *)0); }
inline void adb_decode(int entry) { adb_queueCmd(ADB_PRINT_DECODE,(void*)entry,(void *)0); }

Redo the Database

If you recall from previous posts, my advertising database was just

  1. An Array of structures
  2. Each structure contained the mac address and…
  3. A pointer to a malloc’d copy of the advertising data
typedef struct {
    wiced_bt_ble_scan_results_t *result;
    uint8_t *data;
} adb_adv_t ;

#define ADB_MAX_SIZE (40)
adb_adv_t adb_database[ADB_MAX_SIZE];

Here is a picture of the datastructure

 

Now what I want to do is make the “data” pointer to be a pointer to a linked list of data.  Here is the new definition.

typedef struct {
    uint8_t *data;
    struct adb_adv_data_t *next;
} adb_adv_data_t;

typedef struct {
    wiced_bt_ble_scan_results_t *result;
    int listCount;
    bool record;
    int numSeen;
    adb_adv_data_t *list;
} adb_adv_t ;

The new data structure looks like this

I wanted to limit the number advertising packets that can be stored so I don’t run out of memory.  I am not actually sure how many can be stored, but I suppose a bunch as the chip has 1MB of RAM.  But, I pick 100 which seems like enough to start out with.  I create two variables

  1. A counter for the number of advertising packets that are currently saved
  2. A recording state (are you saving or not)
#define ADB_RECORD_MAX (100)
static int adb_recording_count = 0;
static bool adb_recording = false;

Update the Printing

You probably noticed that I declared two new members of the adb_adv_t structure, specifically numSeen and listCount, which I would like to print out.   I also wanted a visual indication that I am “watching” a device.  The columns are now:

  1. A “*” to indicate that a device is being watched
  2. The device #
  3. The number of packets that I have seen in total from that device
  4. The number of recorded packets for that device
  5. The MAC address
  6. The raw bytes

To do implement this a simple change is made to the print function:

    for(int i=start;i<end;i++)
    {
    
        printf("%s%02d %05d %03d MAC: ",adb_database[i].record?"*":" ",i,adb_database[i].numSeen,adb_database[i].listCount);
        btutil_printBDaddress(adb_database[i].result->remote_bd_addr);
        switch(method)
        {
        
        case ADB_PRINT_METHOD_BYTES:
            printf(" Data: ");
            btutil_adv_printPacketBytes(adb_database[i].list->data);
        break;

        case ADB_PRINT_METHOD_DECODE:
            printf("\n");
            btutil_adv_printPacketDecode(adb_database[i].list->data);
        break;
        } 
        printf("\n");
    }

Update the Add

Now that we have all of the infrastructure in place we need to update the function that saves advertising data.  When an advertising packet comes in you have three situations to consider:

  1. You have never seen the device before
  2. You have seen the device before and you are “watching” it
  3. You have see the device but you are not watching it

In the case where you have never seen the device you need to

  1. Save the scan result
  2. Set the listCount to 1 (you only have one datapoint)
  3. Turn off recording (start with the recording off)
  4. Set the total numSeen to 1 as this is the first packet you have seen
  5. Allocate some memory for the advertising linked list structure
  6. Terminate the linked list
  7. Save the advertising data
  8. Increment the database count (up to the max)
  9. Print out the packet you just saw
    if(entry == -1)
    {
        adb_database[adb_db_count].result = scan_result;
        adb_database[adb_db_count].listCount = 1;
        adb_database[adb_db_count].record = false;
        adb_database[adb_db_count].numSeen = 1;

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = 0;
        current->data = data;

        adb_database[adb_db_count].list = current;

        adb_db_count = adb_db_count + 1;
        if(adb_db_count == ADB_MAX_SIZE)
        {
            printf("ADV Table Max Size\n");
            adb_db_count = adb_db_count - 1;
        }
        else
        {    
            adb_db_print(ADB_PRINT_METHOD_BYTES,adb_db_count-1);
        }
    }

In the case where you have

  1. Seen the device before
  2. You are recording that device
  3. There is room left in the recording buffer

Then you will

  1. Increment number seen
  2. Create memory for the new entry in the linked list
  3. Attach the tail of the linked list to your new entry (you will insert at the front of the list)
  4. Save the data
  5. Increment the number of saved entries
  6. Insert your new packet at the head of the list
  7. Printout the packet
  8. Increment the record count (the total number of packets in the recording buffer)
  9. Then potentially stop recording if you have gotten to the max size.
    else if(adb_database[entry].record && adb_recording_count<ADB_RECORD_MAX && adb_recording)
    {
        adb_database[entry].numSeen += 1;

        adb_adv_data_t *current = malloc(sizeof(adb_adv_data_t));
        current->next = (struct adb_adv_data_t *)adb_database[entry].list;
        current->data = data;
        adb_database[entry].listCount += 1;
        adb_database[entry].list = current;

        adb_db_print(ADB_PRINT_METHOD_BYTES,entry);

        adb_recording_count += 1;
        if(adb_recording_count == ADB_RECORD_MAX)
        {
            adb_recording = false;
            printf("Recording buffer full\n");
        }
    }

In the case where you have seen the device before, but you are not recoding then you will

  1. Update the numSeen
  2. Erase the old packet data
  3. Save the new packet
  4. Erase the “result” (you already have it saved)
    else
    {
        adb_database[entry].numSeen += 1;
        free(adb_database[entry].list->data);
        adb_database[entry].list->data = data;
        free(scan_result);
    }

Add a Watch Command

The watch function is pretty simple.  It just needs to either mark the “record” boolean as true or false.  When I decided to implement this function I decided to make positive numbers be the entry in the table.  But, I also wanted to be able to “watch all” and “watch clear”.  So, I used negative numbers for those two special meanings.  I used a #define in advDatabase.h to define those values.

#define ADB_WATCH_ALL -1
#define ADB_WATCH_CLEAR -2

The function is then pretty simple

  1. If it is watch all… then iterate through the database and turn them on
  2. If it is watch clear … then iterate through the database and turn them off
  3. Otherwise make sure that it is a legal number and toggle it.
static void adb_db_watch(int entry)
{
    if(entry == ADB_WATCH_ALL)
    {
        for(int i=0;i<adb_db_count;i++)
        {
            adb_database[i].record = true;
        }
        return;
    }

    if(entry == ADB_WATCH_CLEAR)
    {
        for(int i=0;i<adb_db_count;i++)
        {
            adb_database[i].record = false;
        }
        return;
    }

    if(entry > adb_db_count-1 || entry < ADB_WATCH_CLEAR)
    {
        printf("Record doesnt exist: %d\n",entry);
        return;      
    }
    adb_database[entry].record = !adb_database[entry].record; 

}

Once I have the infrastructure in place, I then add the watch command to usrcmd.c

static int usrcmd_watch(int argc, char **argv)
{

    if(argc == 2 && !strcmp(argv[1],"all"))
    {
        adb_watch(ADB_WATCH_ALL); // all
        return 0;
    }


    if(argc == 2 && !strcmp(argv[1],"clear"))
    {
        adb_watch(ADB_WATCH_CLEAR);
        return 0;
    }

    if(argc == 2)
    {
        int i;
        sscanf(argv[1],"%d",&i);
        adb_watch(i);
        return 0;
    }

    return 0;
}

Add a Record Command

The record command simply turns on the global bool to either true or false and prints out the number of spaces free in the record “buffer”

                case ADB_RECORD:
                    adb_recording = !adb_recording;
                    printf("Record %s Buffer Entries Free=%d\n",adb_recording?"ON":"OFF",
                        ADB_RECORD_MAX-adb_recording_count);
                break;

And the change to usrcmd.c is also simple.

// record = toggles
static int usrcmd_record(int argc, char **argv)
{
    if(argc == 1)
    {
        adb_record(-1);
        return 0;
    }
    return 0;
}

Add an Erase Command

The erase function is like “watch”, as I overload the “entry” to have an ALL which is setup in advDatabase.h

#define ADB_ERASE_ALL -1

The erase is a bit more complicated than the watch.  When you receive a erase command you will either erase them all by iterating over the whole dates, or just erase one.

                case ADB_ERASE:
                    if((int)msg.data0 == ADB_ERASE_ALL)
                    {
                        for(int i=0;i<adb_db_count;i++)
                        {
                            adb_eraseEntry(i);
                        }
                    }
                    else
                        adb_eraseEntry((int)msg.data0);

                    printf("Record Buffer Free %d\n",ADB_RECORD_MAX-adb_recording_count);
                break;

The individual eraseEntry function checks to make sure that you have a legal “entry”.  Then it follows the linked list “freeing” the data structures.

static void adb_eraseEntry(int entry)
{
    if(entry > adb_db_count-1 || entry<0)
    {
        printf("Erase Entry Not Found %d\n",entry);
        return;
    }

    adb_adv_data_t *ptr;
    ptr = (adb_adv_data_t *)adb_database[entry].list->next;
    adb_database[entry].list->next = 0;
    while(ptr)
    {
        adb_adv_data_t *next;
        next = (adb_adv_data_t *)ptr->next;
        free(ptr->data);
        free(ptr);
        adb_database[entry].listCount -= 1;
        adb_recording_count -= 1;
        ptr = next;
    }
}

And, of course, you need to add the command to usrcmd.c

// erase
// erase #
static int usrcmd_erase(int argc, char **argv)
{
    if(argc > 2)
    {
        return 0;
    }

    if(argc == 1)
    {
        adb_erase(ADB_ERASE_ALL);
        return 0;
    }

    int i;
    sscanf(argv[1],"%d",&i);
    adb_erase(i);
    return 0;    

}

Now when you build and program the kit you can turn on/off recording and erase and….

In the next post I will add

  1. Smarter printing
  2. A “filter” to eliminate duplicate advertising packets

AnyCloud Bluetooth Advertising Scanner (Part 6)

Summary

In part 6 of this series I will update the AnyCloud BLE Advertising Scanner to decode advertising packets into a more human readable textual output

Story

We are now 6 (or maybe 7 depending on how you count) articles into this series and we are still looking at raw bytes.  I have gotten to where I am pretty good at understanding those bytes, but that is now way to roll.  You might remember from the article on the IoT Expert Bluetooth Utility library that there were a some interesting functions defined in the header.  Here it is:

wiced_bool_t btutil_isEddystone(uint8_t *data);
wiced_bool_t btutil_is_iBeacon(uint8_t *data);
wiced_bool_t btutil_isCypress(uint8_t *data);

int btutil_adv_len(uint8_t *packet);
void btutil_adv_printPacketDecode(uint8_t *packet);
void btutil_adv_printPacketBytes(uint8_t *packet);

Lets transform our  project from part 6 to use these functions.  In this article I will

  • Redo the print bytes (to be smarter) functionality and to use the built in function
  • Rework the logic for the “print” command implementation
  • Add a new command “decode” which will run the decode function

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Replace two code blocks with function calls

Do you remember this block of code?  It print’s out the 6-bytes of the Bluetooth Address.

    for(int i=0;i<BD_ADDR_LEN;i++)
    {
        printf("%02X:",adb_database[entry].result->remote_bd_addr[i]);
    }

You might have noticed that this function already exists in the BT Utility Library.  Use it.

    btutil_printBDaddress(adb_database[entry].result->remote_bd_addr);

Then you remember this block of code which iterates through and advertising packet and prints out the raw bytes?

// Print the RAW Data of the ADV Packet
    printf(" Data: ");
    int i=0;
    while(adb_database[entry].data[i])
    {
        for(int j=0;j<adb_database[entry].data[i];j++)
        {
            printf("%02X ",adb_database[entry].data[i+1+j]);
        }
        i = i + adb_database[entry].data[i]+1;
    }

Well, it exists in the library as well.  Use it.

btutil_adv_printPacketBytes(adb_database[entry].data);

Fix the “print” Command

In the previous implementation I had two functions for “print”.  The first one printed one entry and the second one printed the whole table.  I decided that I didnt really like this logic, so I compressed those two functions into one function.  Specifically, it take a number “entry”.  If that number is -1 then it will print the whole table.

static void adb_db_printRawPacket(int entry)
{
    int start,end;
 
    if(entry <= -1)
    {
        start = 0;
        end = adb_db_count;
    }
    else
    {
        start = entry;
        end = entry;
    }

    if(end>adb_db_count)
        end = adb_db_count; 

    for(int i=start;i<=end;i++)
    {
    
        printf("%02d MAC: ",i);
        btutil_printBDaddress(adb_database[i].result->remote_bd_addr);
        printf(" Data: ");
        btutil_adv_printPacketBytes(adb_database[i].data);

        printf("\n");
    }
}

Add a new “decode” Command

The next thing to do is to add a function to print out decoded packets (or the whole table).  So I wrote this:

static void adb_printDecodePacket(int entry)
{
    int start,end;
 
    if(entry == -1)
    {
        start = 0;
        end = adb_db_count;
    }
    else
    {
        start = entry;
        end = entry;
    }

    if(end>adb_db_count)
        end = adb_db_count; 

    for(int i=start;i<=end;i++)
    {

        printf("%02d MAC: ",i);
        btutil_printBDaddress(adb_database[i].result->remote_bd_addr);
        printf("\n");
        btutil_adv_printPacketDecode(adb_database[i].data);
        printf("\n");
    }
}

After finishing that block of code, I realized I had implemented almost exactly the same functionality which two different functions.  So, I decided to redo this by doing this.  Notice that it take in a adb_print_method, in other words raw bytes or decoded packet.

typedef enum {
    ADB_PRINT_METHOD_BYTES,
    ADB_PRINT_METHOD_DECODE,
} adb_print_method_t;

static void adb_db_print(adb_print_method_t method,int entry)
{
    int start,end;
 
    if(entry < 0)
    {
        start = 0;
        end = adb_db_count;
    }
    else
    {
        start = entry;
        end = entry;
    }

    if(end>adb_db_count)
        end = adb_db_count; 

    for(int i=start;i<=end;i++)
    {
    
        printf("%02d MAC: ",i);
        btutil_printBDaddress(adb_database[i].result->remote_bd_addr);
        switch(method)
        {
        
        case ADB_PRINT_METHOD_BYTES:
            printf(" Data: ");
            btutil_adv_printPacketBytes(adb_database[i].data);
        break;

        case ADB_PRINT_METHOD_DECODE:
            printf("\n");
            btutil_adv_printPacketDecode(adb_database[i].data);
        break;
        } 
        printf("\n");
    }
}

I don’t show it here, but after changing this I had to fix up the function calls in several places in the advDatabase.

Add a new command to print decode packets

Now that I have a new method to print packets, I add a command to the database to allow the user to call it:

typedef enum {
    ADB_ADD,
    ADB_PRINT_RAW,
    ADB_PRINT_DECODE,
} adb_cmd_t;

Then in the queue loop:

switch(msg.cmd)
            {
                case ADB_ADD:
                    scan_result = (wiced_bt_ble_scan_results_t *)msg.data0;
                    data = (uint8_t *)msg.data1;
                    adb_db_add(scan_result,data);
                break;
                case ADB_PRINT_RAW:
                    adb_db_print(ADB_PRINT_METHOD_BYTES,(int)msg.data0);
                break;
                case ADB_PRINT_DECODE:
                    adb_db_print(ADB_PRINT_METHOD_DECODE,(int)msg.data0);
                break;
            }

Then the actual function

void adb_printDecode(int entry)
{
    adb_cmdMsg_t msg;
    msg.cmd = ADB_PRINT_DECODE;
    msg.data0 = (void *)entry;
    xQueueSend(adb_cmdQueue,&msg,0); // If the queue is full... oh well
}

Then add it to advDatabase.h

void adb_printDecode(int entry);

Finally to the usercmd.c

static int usrcmd_printDecode(int argc, char **argv)
{
    if(argc == 1)
    {
        adb_printDecode(-1);
    }

    if(argc == 2)
    {
        int val;
        sscanf(argv[1],"%d",&val);
        adb_printDecode(val);
    }
    return 0;
}

Program and Test

When I actually program the scanner you can see that I can print out 1 item.  OR I can decode one item.  Notice that one contains 3 fields

  • flags
  • Tx Power Level
  • Manufacturers data.  Apparently an Apple something or the other

And I can print the whole table

Or decode the whole table.

 

AnyCloud Bluetooth Advertising Scanner (Part 5)

Summary

In this article I will add a new task to the AnyCloud BLE Advertising Scanning application which will save the advertising data into a database.

Story

There is still a boatload of mostly unintelligible advertising data coming ripping onto our screen.  It is FINALLY time to start fixing that.  In this article I will create a new task called the advertising database task which will hold the history of advertising packets that I have seen.  I will update the Bluetooth Manager task to submit the advertising packets to a queue running in the advertising database task.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Create an Advertising Data Database Task

We need to create the file advertisingDatabase.h which will hold the task prototype (so that main can get going).

#pragma once

void adb_task(void *arg);

Then create the advertisingDatabase.c to hold the actual database code.  It will start with the definition of messages which can be sent to the task.  For now just “ADB_ADD”.  To make things a little bit simpler these command can have two data elements (which I call data0 and data1).  Then the main part of the task just

  1. Creates the queue to manage the messages
  2. Process the message until the end of time
#include "FreeRTOS.h"
#include "queue.h"

static QueueHandle_t adb_cmdQueue;
typedef enum {
    ADB_ADD,
} adb_cmd_t;

typedef struct
{
    adb_cmd_t cmd;
    void *data0;
    void *data1;
} adb_cmdMsg_t;

void adb_task(void *arg)
{
    // setup the queue
    adb_cmdMsg_t msg;

    adb_cmdQueue = xQueueCreate(10,sizeof(adb_cmdMsg_t));
    
    while(1)
    {
        BaseType_t status = xQueueReceive(adb_cmdQueue,&msg,portMAX_DELAY);
        if(status == pdTRUE) 
        {
            switch(msg.cmd)
            {
                case ADB_ADD:
                break;
            }

        }
    }
}

To start the task, you need to add it to main.c.

    xTaskCreate(adb_task,"adv database",configMINIMAL_STACK_SIZE*4,0,1,0);

When I build and program this, you can now see the new task.  Good that working.

AnyCloud> Unhandled Bluetooth Management Event: BTM_LOCAL_IDENTITY_KEYS_REQUEST_EVT
Started BT Stack Succesfully

AnyCloud> tasks
Name          State Priority   Stack  Num
------------------------------------------
usrcmd_ta       X       0       228     5
IDLE            R       0       115     7
Tmr Svc         B       0       223     8
CYBT_HCI_       B       5       950     3
sleep_tas       B       6       221     1
CYBT_BT_T       B       4       1371    2
blinkTask       B       0       98      4
adv datab       B       1       479     6
‘B’ – Blocked
‘R’ – Ready
‘D’ – Deleted (waiting clean up)
‘S’ – Suspended, or Blocked without a timeout
Stack = bytes free at highwater
AnyCloud>

Update the Advertising Database to Accept Submitted ADV Packets

If you recall our original setup was to take advertising packets in the Bluetooth Manager thread and print out the data.  The first thing that we want to fix up is the ability of the advertising database task to accept advertising packets which are pushed to its command queue.   To prepare for this I create two local variables to hold the data.

void adb_task(void *arg)
{
    // setup the queue
    adb_cmdMsg_t msg;
    wiced_bt_ble_scan_results_t *scan_result;
    uint8_t *data;

Then I update the ADB_ADD command.  My first, and really simple fix, is to grab the printing code from the Bluetooth Manager task.  Obviously this won’t be an improvement from the original program as far as the users goes, but it will verify that the tasks are working properly together.

                case ADB_ADD:
                    // Print the MAC Address
                    scan_result = (wiced_bt_ble_scan_results_t *)msg.data0;
                    data = (uint8_t *)msg.data1;

                    printf("MAC: ");
                    for(int i=0;i<BD_ADDR_LEN;i++)
                    {
                        printf("%02X:",scan_result->remote_bd_addr[i]);
                    }
                    // Print the RAW Data of the ADV Packet
                    printf(" Data: ");
                    int i=0;
                    while(data[i])
                    {
                        for(int j=0;j<data[i];j++)
                        {
                            printf("%02X ",data[i+1+j]);
                        }
                        i = i + data[i]+1;
                    }
                    printf("\n");
    
                    free(msg.data0);
                    free(msg.data1);
                break;

Then I add a command to the advertisingDatabase.h which the Bluetooth Manager task can call to submit advertising packets

void adb_addAdv(wiced_bt_ble_scan_results_t *scan_result,void *data);

The actual command in advertisingDatabase.c just takes the advertising information, puts it in a command message, then submits it to the command queue.

void adb_addAdv(wiced_bt_ble_scan_results_t *scan_result,void *data)
{
    adb_cmdMsg_t msg;
    msg.cmd = ADB_ADD;
    msg.data0 = (void *)scan_result;
    msg.data1 = (void *)data;
    xQueueSend(adb_cmdQueue,&msg,0); // If you loose an adv packet it is OK...
}

Update the Bluetooth Manager to Submit Adv Packets

Now I go and edit the bluetoothManager. c to submit packets rather than print them.  To do this I greatly simplify the callback.  There is one VERY important issue to deal with, which is one of those potential religious war issues.  Memory.

When you get the callback from the stack, it gives you POINTERS to data for the advertising packet that reside inside of buffers inside of the stack.  As soon as this callback returns this memory is purged.  To prevent this data from getting cleaned up by the stack I

  1. Malloc some memory for the wiced_bt_ble_scan_results
  2. Malloc some memory for the advertising data
  3. Make a copy of the data
  4. Submit it to the Advertising Database

I KNOW from the spec that the largest data packet is 31-bytes (actually it is 31-bytes + one more field with length 0).  So I know the maximum length is 32-bytes  This means that in many situations I will be copying GARBAGE into my buffer if the packet is less than 32 bytes long.  I think that this is simpler than calculating the length and then only copying that much data.

void btm_advCallback(wiced_bt_ble_scan_results_t *p_scan_result, uint8_t *p_adv_data)
{
    wiced_bt_ble_scan_results_t *scan_result = malloc(sizeof(wiced_bt_ble_scan_results_t));
    uint8_t *data = malloc(32);
   
    memcpy(data,p_adv_data,32);
    memcpy(scan_result,p_scan_result->remote_bd_addr,BD_ADDR_LEN);
    adb_addAdv(scan_result,data);
}

When I run this updated program I should get the same stream of data coming out on the serial port.  Sure enough the new thread is working.

Create an Advertising Data Database

Now, lets create an actual database.  To simplify things my database is just an array of structures.  One structure per bluetooth device.  The structure will contain a pointer to the information about the device it just saw and the actual raw data.

typedef struct {
    wiced_bt_ble_scan_results_t *result;
    uint8_t *data;
} adb_adv_t ;

#define ADB_MAX_SIZE (40)
adb_adv_t adb_database[ADB_MAX_SIZE];
int adb_db_count=0;

Then I will create several helper functions to work with the database

  1. Find devices in the database given a mac address
  2. Print an entry in the database
  3. Add entries to the database

First, find an entry in the database.  This function will search through the database and compare the mac address against the mac address in the database.  When the memcmp ==0 meaning it found a match, it will return that entry.

static int adb_db_find(wiced_bt_device_address_t *add)
{
    int rval=-1;
    for(int i=0;i<adb_db_count;i++)
    {
        if(memcmp(add,&adb_database[i].result->remote_bd_addr,BD_ADDR_LEN)==0)
        {
            rval = i;
            break;
        }
    }
    return rval;
}

The print function will make sure that you asked for a legal entry (much must be greater than 0… and less than the max).  Then it will print out the mac address and the raw data.  In a future post I will add a smarter print out.

static void adb_db_printEntry(int entry)
{
    if(!(entry>= 0 && entry <= adb_db_count))
    {
        printf("Illegal entry\n");
        return;
    }
    printf("%02d MAC: ",entry);

    for(int i=0;i<BD_ADDR_LEN;i++)
    {
        printf("%02X:",adb_database[entry].result->remote_bd_addr[i]);
    }

    // Print the RAW Data of the ADV Packet
    printf(" Data: ");
    int i=0;
    while(adb_database[entry].data[i])
    {
        for(int j=0;j<adb_database[entry].data[i];j++)
        {
            printf("%02X ",adb_database[entry].data[i+1+j]);
        }
        i = i + adb_database[entry].data[i]+1;
    }
    printf("\n");
}

To add an entry to the database, first make sure that it isn’t already in the database.  Then when you are sure that it isn’t the database, you just add the pointers to your table.  You need to make sure and not go beyond the end of the table, and if you did, you will have effectively blown away the last entry in the table.  Oh well.

static void adb_db_add(wiced_bt_ble_scan_results_t *scan_result,uint8_t *data)
{
 
    int entry = adb_db_find(&scan_result->remote_bd_addr);
    if(entry == -1)
    {
        
        adb_database[adb_db_count].result = scan_result;
        adb_database[adb_db_count].data = data;
        adb_db_printEntry(adb_db_count);
        adb_db_count = adb_db_count + 1;
        if(adb_db_count == ADB_MAX_SIZE)
        {
            printf("ADV Table Max Size\n");
            adb_db_count = adb_db_count - 1;
        }
    }
    else
    {
        free(scan_result);
        free(data);
    }
}

Add a Command to Print the Database

Now we want to add the ability to print from the command line.  So add a new command message to the list of legal commands.

typedef enum {
    ADB_ADD,
    ADB_PRINT,
} adb_cmd_t;

Then create a new function to print.  If you send in a “-1” it will print the whole table.  Otherwise just print the individual entry.

static void adb_printTable(int entry)
{
    if(entry == -1)
    {
        for(int i=0;i<adb_db_count;i++)
        {
            adb_db_printEntry(i);
        }

    }
    else
    {
        adb_db_printEntry(entry);
    }
    

}

Now edit usercmd.c to have the new command line.  Notice that I use “sscanf” which obviously has some issues.  Too bad.

static int usrcmd_print(int argc, char **argv)
{

    if(argc == 1)
    {
        adb_print(-1); // Print whole table
    }

    if(argc == 2)
    {
        int val;
        sscanf(argv[1],"%d",&val);
        adb_print(val);
    }

    return 0;
}

When I program the project it immediately prints out a bunch of devices that are at my house.  Then you can see I run the “print” command which prints the table.  Finally P do a print 0 to just print the first entry.

In the next article I will add smarter diagnostics to the advertising packets.

AnyCloud Bluetooth Advertising Scanner (Part 4)

Summary

In this article I update the AnyCloud BLE advertising scanner to use the btutil library that was created in the previous post.  In addition, I add a command queue to the bluetoothManger and enable a new command to turn on and off scanning.

Story

If you have been following along until now, which I imagine that you have if you are reading this,  you will have gotten a vomit of device data blasting out onto your serial console.  This isn’t very helpful.  So now what?  I am going to divide this problem into two parts

  1. Creating a new user command to turn on and off scanning (this article)
  2. Creating a database to manage the data + a set of commands to dump it (next article)

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Add the IoT Expert “btutil” Library

Before we actually start all of the command queue stuff, lets move to the btutil library that I talked about in the previous post.  To do this, add the library using the library manager.

Then delete bt_platform_cfg_settings.h and bt_platform_cfg_settings.c from your project.  Finally Rebuild and make sure that everything still works.  That is it.

Multithreading

Id like to explain that there is now some danger.  That danger comes from the fact that we have multiple tasks which are all accessing data plus functions that are talking to each other ASYNCHRONOUSLY.  Specifically we have:

  1. The Bluetooth Stack task – running the Bluetooth stack and management callback
  2. The Bluetooth Stack APIs – e.g. wiced_bt_ble_observe
  3. The usrcmd task – which is interacting with the user on the serial port and talking to the other tasks
  4. A timer_svc task – which runs software timers
  5. The advertising data (which I will start saving in the next article)

When faced with this situation what I typically like to do is provide thread safe public functions for each of the tasks.  Then any other task can call these functions and know that things are not going to get corrupted by a race condition.

To make the design thread safe, I typically like to put an RTOS Queue between the tasks.  These queues are a safe place to send and receive data in a “thread safe” way.  There are two basic design patterns that can be used

  1. Define a message structure (that gets pushed into the queue) and make it global (via a dot-h).  Define a queue handle and make it global (via a dot-h).  Then let any task build messages and push them into the queue to be received in the task that owns the queue.
  2. Define the message structure and queue.  Then define functions which are global (via a dot-h) which know how to interact with the queue.

I typically think that the 2nd method is better, so that is what I am going to do here.

  1. In BluetoothManager.h I will provide a function called “btm_cmdScan”
  2. The usrcmd task will call the btm_cmdScan function which will
  3. Create a btm_cmdMsg_t with the “scan” command and data of true/false
  4. Then push it into the Bluetooth Manager Command Queue
  5. Where a timer callback in the Bluetooth Manager Task will take it out of the queue
  6. Figure out that it is a “scan” command
  7. Then will either turn on or off scanning

Add a Queue to the Bluetooth Manager Thread

So we need two things a message to push into a queue (just a structure) and we need a queue to push it into.  First the message which is just a structure with two elements.  The first element is a command and the second element is some data of type void.  The meaning of the void *data will be different based on the command.

typedef struct {
	btm_cmd_t cmd;
	void *data;
} btm_cmdMsg_t;

But how about the command?  The command is just an enumerate list of commands which will now start with just one command.

typedef enum {
	BTM_SCAN,
} btm_cmd_t;

And know we need to define the queue.

#include "queue.h"
static QueueHandle_t btm_cmdQueue;

Before you can use the queue you need to initialize it.  The best place to initialize this queue is in the management callback right after the stack gets going.  You can see that I tell FreeRTOS that there is a queue which can hold up to 10 commands.  I also tell it that each command is the sizeof the command message.

    switch (event)
    {
        case BTM_ENABLED_EVT:
            printf("Started BT Stack Succesfully\n");
            btm_cmdQueue = xQueueCreate(10,sizeof(btm_cmdMsg_t));

Now we need to create a way for other tasks to create these command messages.  They will do this by calling a function which we will define in the bluetoothManager.h

void btm_cmdScan(bool enable);

This function will live in bluetoothManager.c and it simply

  1. Creates a command
  2. Set the actual command to scan
  3. Sets the void* data to be enable … in other words start or stop scanning.  Remember that a void * can be anything.  See I cast a bool to a void *
  4. Finally push the data into the command queue
void btm_cmdScan(bool enable)
{
    btm_cmdMsg_t msg;
    msg.cmd = BTM_SCAN;
    msg.data = (void *)enable;
  	xQueueSend(btm_cmdQueue, &msg,0);
}

Add a Timer to Process the Queue

So now we have a method to push items into the queue.  How do we get them out of the queue?  To do that I will use a Bluetooth Stack timer that will run every 50ms.

First, define the timer in bluetoothManager.c

#include "wiced_timer.h"
static wiced_timer_ext_t btm_mgmtQueueTimer;

Then define a function which the timer will call.  This function will

  1. Try to get a message out of the queue
  2. IF there is a message it will use a big switch to look at the possible messages
  3. If the message is a scan
  4. Then call the wiced function to either start “observing” or stop “observing”
static void btm_processBluetoothAppQueue()
{
	btm_cmdMsg_t msg;

	 BaseType_t rval;

	 rval = xQueueReceive( btm_cmdQueue,&msg,0);
	 if(rval == pdTRUE)
	 {
		 switch(msg.cmd)
		 {
		 case BTM_SCAN:
            wiced_bt_ble_observe((wiced_bool_t)msg.data,0,btm_advCallback);
			 break;
		 }
	 }
}

The last thing you need to do is start the timer.  The best place to start the timer is in the management callback where you need to

  1. Create the timer
  2. Tell it to start and run every 50ms
    switch (event)
    {
        case BTM_ENABLED_EVT:
            printf("Started BT Stack Succesfully\n");
            btm_cmdQueue = xQueueCreate(10,sizeof(btm_cmdMsg_t));
            wiced_init_timer_ext (&btm_mgmtQueueTimer, btm_processBluetoothAppQueue,0, WICED_TRUE);
            wiced_start_timer_ext (&btm_mgmtQueueTimer, 50);
        break;

A Potential Threading Bug

When I did the implementation originally I created what I thought was a threading bug.  Specifically I used the FreeRTOS timer to process the queue.  In other words instead of using a wiced_timer_ext_t I used a TimerHandle_t.  So what?

The wiced_timer_ext_t is run INSIDE of the BluetoothStack task where the TimerHandle_t is run inside of the Timer_SVC task.

So what?  I was afraid that the call to wiced_bt_ble_obsere was NOT thread safe and needed to be called inside of the same task as the stack.

After some digging I found out that the Bluetooth Stack is threadsafe, so I worried for no reason.  Well, actually, you can never worry enough about making these kinds of threading bugs because they are viscously difficult to debug.

Add a Scan Off & On Command

The last thing that you need to do is add an actual command to the usercmd task to call the bluetooth manager function to turn on and off scanning.

First, add a new prototype for your new command in usercmd.c.  Then add it to the list of legal commands.

static int usrcmd_scan(int argc, char **argv);


static const cmd_table_t cmdlist[] = {

.... deleted stuff

    { "scan","scan [on|off]", usrcmd_scan},

};

Then create the function to process the command line input and call the btm_scan function.

static int usrcmd_scan(int argc, char **argv)
{

    if(argc != 2)
        return 0;

    if(strcmp(argv[1],"on") == 0)
    {
        btm_cmdScan(true);
    }
    else if(strcmp(argv[1],"off") == 0)
    {
        btm_cmdScan(false);

    }
    return 0;

}

Now build it and run it.  You should still get adv packets barfing all over your screen.  But now you can turn on and off the scanning with “scan on” and “scan off”.  In the next article we will create a database to hold the scan packets.

AnyCloud Bluetooth Utilities Library

Summary

This article is a discussion of a library of utilities functions that support AnyCloud Bluetooth development.  It includes settings to configure the hardware, functions to decode stack events, functions to decode advertising packets etc.

Story

The Cypress, now Infineon, Modus Toolbox team has been working to bring the WICED Bluetooth devices to be closer and more compatible with the PSoC 6 tools.  One of the important enablement things we have done is turn on the WICED Bluetooth Host stack on the PSoC 6 so that it can effectively talk to the CYW43XXX Bluetooth / WiFi combo chips.

As I have been using all of the new stuff I found myself adding my own custom functionality…. and after a while I realized (finally) that I should put all of those little helper things into a library, specifically an IoT Expert library.  For now this library contains:

  • The Bluetooth Platform Configuration Settings
  • Functions to decode stack events
  • Functions to decode advertising packets

but imagine with time I will add more functions and templates.

bt_platform_cfg_settings

As I discussed in the article AnyCloud Bluetooth Advertising Scanner (Part 1), every single AnyCloud BLE Stack project will require a structure of type wiced_bt_cfg_settings_t.  This structure is used to setup the hardware before getting the stack going.  Remember you need to make a call like this to initialize the Bluetooth hardware.

    cybt_platform_config_init(&bt_platform_cfg_settings);

At some point this file will be included automatically for you by the Modus Toolbox team, but for now I have added this to my library.  This file look like this.  Basically a bunch of pin definitions which are set for you automatically by the BSP.  Obviously you can make your own, but this should work on all of the Cypress development kits (I think)

#include "cybt_platform_config.h"
#include "cybsp.h"
#include "wiced_bt_stack.h"

const cybt_platform_config_t bt_platform_cfg_settings =
{
    .hci_config =
    {
        .hci_transport = CYBT_HCI_UART,

        .hci =
        {
            .hci_uart =
            {
                .uart_tx_pin = CYBSP_BT_UART_TX,
                .uart_rx_pin = CYBSP_BT_UART_RX,
                .uart_rts_pin = CYBSP_BT_UART_RTS,
                .uart_cts_pin = CYBSP_BT_UART_CTS,

                .baud_rate_for_fw_download = 115200,
                .baud_rate_for_feature     = 115200,

                .data_bits = 8,
                .stop_bits = 1,
                .parity = CYHAL_UART_PARITY_NONE,
                .flow_control = WICED_TRUE
            }
        }
    },

    .controller_config =
    {
        .bt_power_pin      = CYBSP_BT_POWER,
        .sleep_mode =
        {
            #if (bt_0_power_0_ENABLED == 1) /* BT Power control is enabled in the LPA */
            #if (CYCFG_BT_LP_ENABLED == 1) /* Low power is enabled in the LPA, use the LPA configuration */
            .sleep_mode_enabled = true,
            .device_wakeup_pin = CYCFG_BT_DEV_WAKE_GPIO,
            .host_wakeup_pin = CYCFG_BT_HOST_WAKE_GPIO,
            .device_wake_polarity = CYCFG_BT_DEV_WAKE_POLARITY,
            .host_wake_polarity = CYCFG_BT_HOST_WAKE_IRQ_EVENT
            #else /* Low power is disabled in the LPA, disable low power */
            .sleep_mode_enabled = false
            #endif
            #else /* BT Power control is disabled in the LPA – default to BSP low power configuration */
            .sleep_mode_enabled = true,
            .device_wakeup_pin = CYBSP_BT_DEVICE_WAKE,
            .host_wakeup_pin = CYBSP_BT_HOST_WAKE,
            .device_wake_polarity = CYBT_WAKE_ACTIVE_LOW,
            .host_wake_polarity = CYBT_WAKE_ACTIVE_LOW
            #endif
        }
    },

    .task_mem_pool_size    = 2048
};

btutil_stack

When you startup the Bluetooth Host stack you are responsible for providing a “management callback” which has the function prototype

typedef wiced_result_t (wiced_bt_management_cback_t) (wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data);

The first parameter is an “event” which is  just an enumerated list of possible events by the Bluetooth Host Stack.  Here is the actual list.

enum wiced_bt_management_evt_e {
/* Bluetooth status events */
BTM_ENABLED_EVT,                                /**< Bluetooth controller and host stack enabled. Event data: wiced_bt_dev_enabled_t */
BTM_DISABLED_EVT,                               /**< Bluetooth controller and host stack disabled. Event data: NULL */
BTM_POWER_MANAGEMENT_STATUS_EVT,                /**< Power management status change. Event data: wiced_bt_power_mgmt_notification_t */
BTM_RE_START_EVT,                               /**< Bluetooth controller and host stack re-enabled. Event data: tBTM_ENABLED_EVT */
/* Security events */
BTM_PIN_REQUEST_EVT,                            /**< PIN request (used only with legacy devices). Event data: #wiced_bt_dev_name_and_class_t */
BTM_USER_CONFIRMATION_REQUEST_EVT,              /**< received USER_CONFIRMATION_REQUEST event (respond using #wiced_bt_dev_confirm_req_reply). Event data: #wiced_bt_dev_user_cfm_req_t */
BTM_PASSKEY_NOTIFICATION_EVT,                   /**< received USER_PASSKEY_NOTIFY event. Event data: #wiced_bt_dev_user_key_notif_t */
BTM_PASSKEY_REQUEST_EVT,                        /**< received USER_PASSKEY_REQUEST event @cond DUAL_MODE (respond using #wiced_bt_dev_pass_key_req_reply). Event data: #wiced_bt_dev_user_key_req_t @endcond
@note  BR/EDR Only */
BTM_KEYPRESS_NOTIFICATION_EVT,                  /**< received KEYPRESS_NOTIFY event. Event data: #wiced_bt_dev_user_keypress_t */
BTM_PAIRING_IO_CAPABILITIES_BR_EDR_REQUEST_EVT, /**< Requesting IO capabilities for BR/EDR pairing. Event data: #wiced_bt_dev_bredr_io_caps_req_t 
@note  BR/EDR Only */
BTM_PAIRING_IO_CAPABILITIES_BR_EDR_RESPONSE_EVT,/**< Received IO capabilities response for BR/EDR pairing. Event data: @cond DUAL_MODE #wiced_bt_dev_bredr_io_caps_rsp_t @endcond
@note  BR/EDR Only*/
BTM_PAIRING_IO_CAPABILITIES_BLE_REQUEST_EVT,    /**< Requesting IO capabilities for BLE pairing. Slave can check peer io capabilities in event data before updating with local io capabilities. Event data: #wiced_bt_dev_ble_io_caps_req_t */
BTM_PAIRING_COMPLETE_EVT,                       /**< received SIMPLE_PAIRING_COMPLETE event. Event data: #wiced_bt_dev_pairing_cplt_t */
BTM_ENCRYPTION_STATUS_EVT,                      /**< Encryption status change. Event data: #wiced_bt_dev_encryption_status_t */
BTM_SECURITY_REQUEST_EVT,                       /**< Security request (respond using #wiced_bt_ble_security_grant). Event data: #wiced_bt_dev_security_request_t */
BTM_SECURITY_FAILED_EVT,                        /**< Security procedure/authentication failed. Event data: #wiced_bt_dev_security_failed_t */
BTM_SECURITY_ABORTED_EVT,                       /**< Security procedure aborted locally, or unexpected link drop. Event data: #wiced_bt_dev_name_and_class_t */
BTM_READ_LOCAL_OOB_DATA_COMPLETE_EVT,           /**< Result of reading local OOB data @cond DUAL_MODE (#wiced_bt_dev_read_local_oob_data). Event data: #wiced_bt_dev_local_oob_t @endcond 
@note  BR/EDR Only */
BTM_REMOTE_OOB_DATA_REQUEST_EVT,                /**< OOB data from remote device @cond DUAL_MODE (respond using #wiced_bt_dev_remote_oob_data_reply). Event data: #wiced_bt_dev_remote_oob_t @endcond 
@note  BR/EDR Only */
BTM_PAIRED_DEVICE_LINK_KEYS_UPDATE_EVT,         /**< Updated remote device link keys (store device_link_keys to  NV memory). This is the place to
verify that the correct link key has been generated. Event data: #wiced_bt_device_link_keys_t */
BTM_PAIRED_DEVICE_LINK_KEYS_REQUEST_EVT,        /**< Request for stored remote device link keys (restore device_link_keys from NV memory). If successful, return WICED_BT_SUCCESS. Event data: #wiced_bt_device_link_keys_t */
BTM_LOCAL_IDENTITY_KEYS_UPDATE_EVT,             /**< Update local identity key (stored local_identity_keys NV memory). Event data: #wiced_bt_local_identity_keys_t */
BTM_LOCAL_IDENTITY_KEYS_REQUEST_EVT,            /**< Request local identity key (get local_identity_keys from NV memory). If successful, return WICED_BT_SUCCESS. Event data: #wiced_bt_local_identity_keys_t */
BTM_BLE_SCAN_STATE_CHANGED_EVT,                 /**< BLE scan state change. Event data: #wiced_bt_ble_scan_type_t */
BTM_BLE_ADVERT_STATE_CHANGED_EVT,               /**< BLE advertisement state change. Event data: #wiced_bt_ble_advert_mode_t */
/* BLE Secure Connection events */
BTM_SMP_REMOTE_OOB_DATA_REQUEST_EVT,            /**< SMP remote oob data request. Reply using wiced_bt_smp_oob_data_reply. Event data: #wiced_bt_smp_remote_oob_req_t  */
BTM_SMP_SC_REMOTE_OOB_DATA_REQUEST_EVT,         /**< LE secure connection remote oob data request. Reply using wiced_bt_smp_sc_oob_reply. Event data: #wiced_bt_smp_sc_remote_oob_req_t 
@note  BR/EDR Only */
BTM_SMP_SC_LOCAL_OOB_DATA_NOTIFICATION_EVT,     /**< LE secure connection local OOB data (wiced_bt_smp_create_local_sc_oob_data). Event data: #wiced_bt_smp_sc_local_oob_t */
BTM_SCO_CONNECTED_EVT,                          /**< SCO connected event. Event data: @cond DUAL_MODE #wiced_bt_sco_connected_t @endcond
@note  BR/EDR Only */
BTM_SCO_DISCONNECTED_EVT,                       /**< SCO disconnected event. Event data: @cond #wiced_bt_sco_disconnected_t @endcond
@note  BR/EDR Only */
BTM_SCO_CONNECTION_REQUEST_EVT,                 /**< SCO connection request event. Event data: @cond #wiced_bt_sco_connection_request_t @endcond
@note  BR/EDR Only */
BTM_SCO_CONNECTION_CHANGE_EVT,                  /**< SCO connection change event. Event data: @cond #wiced_bt_sco_connection_change_t @endcond
@note  BR/EDR Only */
BTM_BLE_CONNECTION_PARAM_UPDATE,                /**< BLE connection parameter update. Event data: #wiced_bt_ble_connection_param_update_t */
BTM_BLE_PHY_UPDATE_EVT,                         /**< BLE Physical link update. Event data: wiced_bt_ble_phy_update_t */
BTM_LPM_STATE_LOW_POWER,                        /**< BT device wake has been deasserted. Used for Host Stack Use Case. */
BTM_MULTI_ADVERT_RESP_EVENT,                    /**< Multi adv command status event Used for the status of the command sent */
#if SMP_CATB_CONFORMANCE_TESTER == TRUE
BTM_SMP_SC_PEER_INFO_EVT                        /** The Secure Connections support information of the peer device */
#endif
};

While you are trying to figure out what is going on during the development, it is very useful to be able to print out the name of the events (instead of the numbers).  In other words instead of doing

printf("Event = %02X\n",event);

it is way better to do

printf("Event Name=%s\n",btutil_getBTEventName(event));

While I was looking at an example project I found this function which I thought was awesome.

const char *btutil_getBTEventName(wiced_bt_management_evt_t event)
{
switch ( (int)event )
{
CASE_RETURN_STR(BTM_ENABLED_EVT)
CASE_RETURN_STR(BTM_DISABLED_EVT)
CASE_RETURN_STR(BTM_POWER_MANAGEMENT_STATUS_EVT)
CASE_RETURN_STR(BTM_PIN_REQUEST_EVT)
CASE_RETURN_STR(BTM_USER_CONFIRMATION_REQUEST_EVT)
CASE_RETURN_STR(BTM_PASSKEY_NOTIFICATION_EVT)
CASE_RETURN_STR(BTM_PASSKEY_REQUEST_EVT)
CASE_RETURN_STR(BTM_KEYPRESS_NOTIFICATION_EVT)
CASE_RETURN_STR(BTM_PAIRING_IO_CAPABILITIES_BR_EDR_REQUEST_EVT)
CASE_RETURN_STR(BTM_PAIRING_IO_CAPABILITIES_BR_EDR_RESPONSE_EVT)
CASE_RETURN_STR(BTM_PAIRING_IO_CAPABILITIES_BLE_REQUEST_EVT)
CASE_RETURN_STR(BTM_PAIRING_COMPLETE_EVT)
CASE_RETURN_STR(BTM_ENCRYPTION_STATUS_EVT)
CASE_RETURN_STR(BTM_SECURITY_REQUEST_EVT)
CASE_RETURN_STR(BTM_SECURITY_FAILED_EVT)
CASE_RETURN_STR(BTM_SECURITY_ABORTED_EVT)
CASE_RETURN_STR(BTM_READ_LOCAL_OOB_DATA_COMPLETE_EVT)
CASE_RETURN_STR(BTM_REMOTE_OOB_DATA_REQUEST_EVT)
CASE_RETURN_STR(BTM_PAIRED_DEVICE_LINK_KEYS_UPDATE_EVT)
CASE_RETURN_STR(BTM_PAIRED_DEVICE_LINK_KEYS_REQUEST_EVT)
CASE_RETURN_STR(BTM_LOCAL_IDENTITY_KEYS_UPDATE_EVT)
CASE_RETURN_STR(BTM_LOCAL_IDENTITY_KEYS_REQUEST_EVT)
CASE_RETURN_STR(BTM_BLE_SCAN_STATE_CHANGED_EVT)
CASE_RETURN_STR(BTM_BLE_ADVERT_STATE_CHANGED_EVT)
CASE_RETURN_STR(BTM_SMP_REMOTE_OOB_DATA_REQUEST_EVT)
CASE_RETURN_STR(BTM_SMP_SC_REMOTE_OOB_DATA_REQUEST_EVT)
CASE_RETURN_STR(BTM_SMP_SC_LOCAL_OOB_DATA_NOTIFICATION_EVT)
CASE_RETURN_STR(BTM_SCO_CONNECTED_EVT)
CASE_RETURN_STR(BTM_SCO_DISCONNECTED_EVT)
CASE_RETURN_STR(BTM_SCO_CONNECTION_REQUEST_EVT)
CASE_RETURN_STR(BTM_SCO_CONNECTION_CHANGE_EVT)
CASE_RETURN_STR(BTM_BLE_CONNECTION_PARAM_UPDATE)
#ifdef CYW20819A1
CASE_RETURN_STR(BTM_BLE_PHY_UPDATE_EVT)
#endif
}
return NULL;
}

And then I learned something new when I looked at the “function” CASE_RETURN_STR which used compiler trick to turn an enumerated value into a string.

#define CASE_RETURN_STR(enum_val)          case enum_val: return #enum_val;

This allows you to do this in your management callback (notice line 16 where the string is printed out)

wiced_result_t app_bt_management_callback(wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data)
{
wiced_result_t result = WICED_BT_SUCCESS;
switch (event)
{
case BTM_ENABLED_EVT:
if (WICED_BT_SUCCESS == p_event_data->enabled.status)
{
printf("Started BT Stack Succesfully\n");
wiced_bt_ble_observe(WICED_TRUE,0,obv_callback);
}
break;
default:
printf("Unhandled Bluetooth Management Event: %s\n", btutil_getBTEventName(event));
break;
}
return result;
}

It turns out that there are several other places where the stack gives you an event-ish thing.  So these functions were created as well

#pragma once
const char *btutil_getBTEventName(wiced_bt_management_evt_t event);
const char *btutil_getBLEAdvertModeName(wiced_bt_ble_advert_mode_t mode);
const char *btutil_getBLEGattDisconnReasonName(wiced_bt_gatt_disconn_reason_t reason);
const char *btutil_getBLEGattStatusName(wiced_bt_gatt_status_t status);

btutil_adv_decode

In AnyCloud Bluetooth Advertising Scanner (Part 3) I discussed the format of the advertising packet.  So I created functions which will decode the data in the advertising packets.  More on the future article AnyCloud Bluetooth Advertising Scanner (Part 4 or maybe 5 or maybe 6).  Here are the functions:

#pragma once
wiced_bool_t btutil_isEddystone(uint8_t *data);
wiced_bool_t btutil_is_iBeacon(uint8_t *data);
wiced_bool_t btutil_isCypress(uint8_t *data);
int btutil_adv_len(uint8_t *packet);
void btutil_adv_printPacketDecode(uint8_t *packet);
void btutil_adv_printPacketBytes(uint8_t *packet);

btutil

And because I like to have just one include to get access to all of the function I created “btutil.h” which just includes all of the headers in one place.

#pragma once
#include "btutil_adv_decode.h"
#include "btutil_stack.h"
#include "btutil_general.h"
#include "bt_platform_cfg_settings.h"

Add to the IoT Expert Manifest

In order to set it up for my library to live in the library manager I updated the IoT Expert Manifest file to have a link to the GitHub repository

<middleware>
<name>Bluetooth Utilities</name>
<id>btutil</id>
<uri>https://github.com/iotexpert/btutil</uri>
<desc>A library of Bluetooth Debugging Utilties for Cypress PSoC6 Anycloud</desc>
<category>IoT Expert</category>
<req_capabilities>psoc6</req_capabilities>
<versions>
<version flow_version="1.0,2.0">
<num>master</num>
<commit>master</commit>
<desc>master</desc>
</version>
</versions>
</middleware>

And now the library manager has the IoT Expert Bluetooth Utilities.

 

 

AnyCloud Bluetooth Advertising Scanner (Part 2)

Summary

The second article in a series discussing the creation of a PSoC 6 + CYW43xxx Advertising Scanner using the AnyCloud SDK.  This article will use the learning from Part 1 to create a template project that starts the BLE stack.

Story

In the previous article I discussed the structure of the Cypress/Infineon Bluetooth Stack and its integration into AnyCloud.  A bunch of “theory”, well I say BS to that.  Let’s build something.

There are

Article Topic
AnyCloud Bluetooth Advertising Scanner (Part 1) Introduction to AnyCloud Bluetooth Advertising
AnyCloud Bluetooth Advertising Scanner (Part 2) Creating an AnyCloud Bluetooth project
AnyCloud Bluetooth Advertising Scanner (Part 3) Adding Observing functionality to the project
AnyCloud Bluetooth Utilities Library A set of APIs for enhancement of the AnyCloud Library
AnyCloud Bluetooth Advertising Scanner (Part 4) Adding a command line to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 5) Adding a history database to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 6) Decoding advertising packets
AnyCloud Bluetooth Advertising Scanner (Part 7) Adding recording commands to the command line
AnyCloud Bluetooth Advertising Scanner (Part 8) Adding filtering to the scanner
AnyCloud Bluetooth Advertising Scanner (Part 9) Improve the print and add packet age
AnyCloud Bluetooth Advertising Scanner (Part 10) Sort the database

All of the code can be found at git@github.com:iotexpert/AnyCloudBLEScanner.git and https://github.com/iotexpert/AnyCloudBLEScanner.git

There are git tags in place starting at part 5 so that you can look at just that version of the code.  "git tag" to list the tags.  And "git checkout part6" to look at the part 6 version of the code.

You can also create a new project with this is a template if you have the IoT Expert Manifest Files installed

Recall from Part 1 that you need three things to startup the Bluetooth Stack

  • The Hardware Configuration Structure that matches : cybt_platform_config_t
  • The Bluetooth Stack Configuration Structure that matches : wiced_bt_cfg_settings_t
  • The Bluetooth Management Callback that matches : typedef wiced_result_t (wiced_bt_management_cback_t) (wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data);

Then you need to call

  • The hardware initialization function : cybt_platform_config_init
  • The stack initialization function : wiced_bt_stack_init

Ok let’s do this!

Basic Project

You can do all of these steps from the Eclipse IDE for ModusToolbox.  Or you can do it from the individual programs and the command line.  I like Visual Studio code, so this article will be done completely from the command line and individual configurators.

Run the new project creator from the start menu.  Start by creating a project for the development kit that you have, in my case the one currently plugged into my computer is the CY8CKIT-062S2-43012, so that is what I pick.  But, this project will work with any of the WiFI/BT combo chips attached to PSoC 6.

In previous articles I discussed the template that I use to get things going with FreeRTOS.  I won’t discuss that here, but I want FreeRTOS and the NTShell, so pick the IoT Expert FreeRTOS NTShell Template.

After about a minute you should have a project.  I always like to build the project to make sure that everything is working before I get too far down the road of modifying anything.  Run “make -j build”

arh (master) AnyCloudBLEScanner $ make -j build
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Prebuild operations complete
Commencing build operations...
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Initializing build: MTBShellTemplate Debug CY8CKIT-062S2-43012 GCC_ARM
Auto-discovery in progress...
-> Found 205 .c file(s)
-> Found 46 .S file(s)
-> Found 23 .s file(s)
-> Found 0 .cpp file(s)
-> Found 0 .o file(s)
-> Found 6 .a file(s)
-> Found 503 .h file(s)
-> Found 0 .hpp file(s)
-> Found 0 resource file(s)
Applying filters...
Auto-discovery complete
Constructing build rules...
Build rules construction complete
==============================================================================
= Building application =
==============================================================================
Generating compilation database file...
-> ./build/compile_commands.json
Compilation database file generation complete
Building 193 file(s)
Compiling app file lowPower.c
Compiling app file main.c
Compiling app file usrcmd.c
Compiling ext file startup_psoc6_02_cm4.S
..... a bunch of lines deleted
Compiling ext file psoc6_01_cm0p_sleep.c
Compiling ext file psoc6_02_cm0p_sleep.c
Compiling ext file psoc6_03_cm0p_sleep.c
Compiling ext file psoc6_04_cm0p_sleep.c
Compiling ext file cy_retarget_io.c
Linking output file MTBShellTemplate.elf
==============================================================================
= Build complete =
==============================================================================
Calculating memory consumption: CY8C624ABZI-S2D44 GCC_ARM -Og
---------------------------------------------------- 
| Section Name         |  Address      |  Size       | 
---------------------------------------------------- 
| .cy_m0p_image        |  0x10000000   |  6044       | 
| .text                |  0x10002000   |  54876      | 
| .ARM.exidx           |  0x1000f65c   |  8          | 
| .copy.table          |  0x1000f664   |  24         | 
| .zero.table          |  0x1000f67c   |  8          | 
| .data                |  0x080022e0   |  1688       | 
| .cy_sharedmem        |  0x08002978   |  8          | 
| .noinit              |  0x08002980   |  148        | 
| .bss                 |  0x08002a14   |  2136       | 
| .heap                |  0x08003270   |  1029520    | 
---------------------------------------------------- 
Total Internal Flash (Available)          2097152    
Total Internal Flash (Utilized)           64812      
Total Internal SRAM (Available)           1046528    
Total Internal SRAM (Utilized with heap)  1033500    

Then to be sure it is working, program the development kit.

arh (master) AnyCloudBLEScanner $ make program
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Prebuild operations complete
Commencing build operations...
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Initializing build: MTBShellTemplate Debug CY8CKIT-062S2-43012 GCC_ARM
Auto-discovery in progress...
-> Found 205 .c file(s)
-> Found 46 .S file(s)
-> Found 23 .s file(s)
-> Found 0 .cpp file(s)
-> Found 0 .o file(s)
-> Found 6 .a file(s)
-> Found 503 .h file(s)
-> Found 0 .hpp file(s)
-> Found 0 resource file(s)
Applying filters...
Auto-discovery complete
Constructing build rules...
Build rules construction complete
==============================================================================
= Building application =
==============================================================================
Generating compilation database file...
-> ./build/compile_commands.json
Compilation database file generation complete
Building 193 file(s)
==============================================================================
= Build complete =
==============================================================================
Calculating memory consumption: CY8C624ABZI-S2D44 GCC_ARM -Og
---------------------------------------------------- 
| Section Name         |  Address      |  Size       | 
---------------------------------------------------- 
| .cy_m0p_image        |  0x10000000   |  6044       | 
| .text                |  0x10002000   |  54876      | 
| .ARM.exidx           |  0x1000f65c   |  8          | 
| .copy.table          |  0x1000f664   |  24         | 
| .zero.table          |  0x1000f67c   |  8          | 
| .data                |  0x080022e0   |  1688       | 
| .cy_sharedmem        |  0x08002978   |  8          | 
| .noinit              |  0x08002980   |  148        | 
| .bss                 |  0x08002a14   |  2136       | 
| .heap                |  0x08003270   |  1029520    | 
---------------------------------------------------- 
Total Internal Flash (Available)          2097152    
Total Internal Flash (Utilized)           64812      
Total Internal SRAM (Available)           1046528    
Total Internal SRAM (Utilized with heap)  1033500    
Programming target device... 
Open On-Chip Debugger 0.10.0+dev-4.1.0.1058 (2020-08-11-03:45)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.org/doc/doxygen/bugs.html
Info : auto-selecting first available session transport "swd". To override use 'transport select <transport>'.
adapter speed: 2000 kHz
adapter srst delay: 25
adapter srst pulse_width: 25
** Auto-acquire enabled, use "set ENABLE_ACQUIRE 0" to disable
cortex_m reset_config sysresetreq
cortex_m reset_config sysresetreq
Info : Using CMSIS loader 'CY8C6xxA_SMIF' for bank 'psoc6_smif0_cm0' (footprint 14672 bytes)
Warn : SFlash programming allowed for regions: USER, TOC, KEY
Info : CMSIS-DAP: SWD  Supported
Info : CMSIS-DAP: FW Version = 2.0.0
Info : CMSIS-DAP: Interface Initialised (SWD)
Info : SWCLK/TCK = 1 SWDIO/TMS = 1 TDI = 0 TDO = 0 nTRST = 0 nRESET = 1
Info : CMSIS-DAP: Interface ready
Info : KitProg3: FW version: 1.14.514
Info : KitProg3: Pipelined transfers disabled, please update the firmware
Info : VTarget = 3.215 V
Info : kitprog3: acquiring the device...
Info : clock speed 2000 kHz
Info : SWD DPIDR 0x6ba02477
Info : psoc6.cpu.cm0: hardware has 4 breakpoints, 2 watchpoints
***************************************
** Silicon: 0xE453, Family: 0x102, Rev.: 0x12 (A1)
** Detected Device: CY8C624ABZI-S2D44
** Detected Main Flash size, kb: 2048
** Flash Boot version: 3.1.0.378
** Chip Protection: NORMAL
***************************************
Info : psoc6.cpu.cm4: hardware has 6 breakpoints, 4 watchpoints
Info : starting gdb server for psoc6.cpu.cm0 on 3333
Info : Listening on port 3333 for gdb connections
Info : starting gdb server for psoc6.cpu.cm4 on 3334
Info : Listening on port 3334 for gdb connections
Info : SWD DPIDR 0x6ba02477
Info : kitprog3: acquiring the device...
psoc6.cpu.cm0 halted due to debug-request, current mode: Thread 
xPSR: 0x41000000 pc: 0x00000190 msp: 0x080ff800
** Device acquired successfully
** psoc6.cpu.cm4: Ran after reset and before halt...
psoc6.cpu.cm4 halted due to debug-request, current mode: Thread 
xPSR: 0x01000000 pc: 0x0000012a msp: 0x080ff800
** Programming Started **
auto erase enabled
Info : Flash write discontinued at 0x1000179c, next section at 0x10002000
Info : Padding image section 0 at 0x1000179c with 100 bytes (bank write end alignment)
[100%] [################################] [ Erasing     ]
[100%] [################################] [ Programming ]
Info : Padding image section 1 at 0x1000fd24 with 220 bytes (bank write end alignment)
[100%] [################################] [ Erasing     ]
[100%] [################################] [ Programming ]
wrote 62976 bytes from file /Users/arh/mtw/AnyCloudBLEScanner/build/CY8CKIT-062S2-43012/Debug/MTBShellTemplate.hex in 2.069358s (29.719 KiB/s)
** Programming Finished **
** Verify Started **
verified 62656 bytes in 0.122208s (500.683 KiB/s)
** Verified OK **
** Resetting Target **
Info : SWD DPIDR 0x6ba02477
shutdown command invoked
Info : psoc6.dap: powering down debug domain...
arh (master) AnyCloudBLEScanner $

When that is done, open up a terminal window and you should have a functioning base project.  Notice that I ran “help” and “tasks” from the command shell.

Now that we have a basic project working, add the Bluetooth libraries.  Run the library manager by typing “make modlibs”.  Then select “bluetooth-freertos” and the library manager will automatically select the other libraries you need.  Press Update then Close.

Next, run the bluetooth configurator by running “make config_bt”  This tool will help you make the bluetooth stack configuration structure.  When the configurator starts, press “New”

Then select our device (the PSoC 6 and the Combo chip)

Click on the “GAP Settings”.  Then press the Plus and add “Observer configuration”

Then setup the scan settings (more detail on these numbers in the next article)

  • Low duty scan window (ms) = 60
  • Low duty scan interval (ms) = 60
  • Low duty scan timeout = deselected (meaning no timeout)

Then save your configuration file.  Notice that I called it “btconfig”

When you are done you will have a directory called “GeneratedSource” inside of your project with the needed files.

The next step is to fix up the Makefile.  I like changing the name of the “App”.

# Name of application (used to derive name of final linked file).
APPNAME=AnyCloudBLEScanner

Then you need the “FREERTOS WICED_BLE” components.

# Enable optional code that is ordinarily disabled by default.
#
# Available components depend on the specific targeted hardware and firmware
# in use. In general, if you have
#
#    COMPONENTS=foo bar
#
# ... then code in directories named COMPONENT_foo and COMPONENT_bar will be
# added to the build
#
COMPONENTS=FREERTOS WICED_BLE

If you run make vscode it will update the workspace with all of the stuff needed for Visual Studio Code to be able to find all of the files.

arh (master) AnyCloudBLEScanner $ make vscode
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Prebuild operations complete
Commencing build operations...
Tools Directory: /Applications/ModusToolbox/tools_2.2
CY8CKIT-062S2-43012.mk: ../mtb_shared/TARGET_CY8CKIT-062S2-43012/latest-v2.X/CY8CKIT-062S2-43012.mk
Initializing build: MTBShellTemplate Debug CY8CKIT-062S2-43012 GCC_ARM
Auto-discovery in progress...
-> Found 230 .c file(s)
-> Found 46 .S file(s)
-> Found 23 .s file(s)
-> Found 0 .cpp file(s)
-> Found 0 .o file(s)
-> Found 22 .a file(s)
-> Found 561 .h file(s)
-> Found 0 .hpp file(s)
-> Found 0 resource file(s)
Applying filters...
Auto-discovery complete
Constructing build rules...
Build rules construction complete
==============================================================================
= Generating IDE files =
==============================================================================
==============================================================================
= Building application =
==============================================================================
Generating compilation database file...
-> ./build/compile_commands.json
Compilation database file generation complete
echo "The existing MTBShellTemplate.code-workspace file has been saved to .vscode/backup";
The existing MTBShellTemplate.code-workspace file has been saved to .vscode/backup
The existing c_cpp_properties.json file has been saved to .vscode/backup
The existing launch.json file has been saved to .vscode/backup
Modifying existing settings.json file. Check against the backup copy in .vscode/backup
The existing tasks.json file has been saved to .vscode/backup
Generated Visual Studio Code files: c_cpp_properties.json launch.json openocd.tcl settings.json tasks.json
J-Link users, please see the comments at the top of the launch.json
file about setting the location of the gdb-server.
Instructions:
1. Review the modustoolbox.toolsPath property in .vscode/settings.json
2. Open VSCode
3. Install "C/C++" and "Cortex-Debug" extensions
4. File->Open Folder (Welcome page->Start->Open folder)
5. Select the app root directory and open
6. Builds: Terminal->Run Task
7. Debugging: "Bug icon" on the left-hand pane
arh (master) AnyCloudBLEScanner $

Inside of Visual Studio Code, create a new file called “bt_platform_cfg_settings.h” and add:

#include "cybt_platform_config.h"
#include "cybsp.h"
#include "wiced_bt_stack.h"
extern const cybt_platform_config_t bt_platform_cfg_settings;

Inside of Visual Studio Code, create a new file called “bt_platform_cfg_settings.c” and add:

#include "cybt_platform_config.h"
#include "cybsp.h"
#include "wiced_bt_stack.h"

const cybt_platform_config_t bt_platform_cfg_settings =
{
    .hci_config =
    {
        .hci_transport = CYBT_HCI_UART,

        .hci =
        {
            .hci_uart =
            {
                .uart_tx_pin = CYBSP_BT_UART_TX,
                .uart_rx_pin = CYBSP_BT_UART_RX,
                .uart_rts_pin = CYBSP_BT_UART_RTS,
                .uart_cts_pin = CYBSP_BT_UART_CTS,

                .baud_rate_for_fw_download = 115200,
                .baud_rate_for_feature     = 115200,

                .data_bits = 8,
                .stop_bits = 1,
                .parity = CYHAL_UART_PARITY_NONE,
                .flow_control = WICED_TRUE
            }
        }
    },

    .controller_config =
    {
        .bt_power_pin      = CYBSP_BT_POWER,
        .sleep_mode =
        {
            #if (bt_0_power_0_ENABLED == 1) /* BT Power control is enabled in the LPA */
            #if (CYCFG_BT_LP_ENABLED == 1) /* Low power is enabled in the LPA, use the LPA configuration */
            .sleep_mode_enabled = true,
            .device_wakeup_pin = CYCFG_BT_DEV_WAKE_GPIO,
            .host_wakeup_pin = CYCFG_BT_HOST_WAKE_GPIO,
            .device_wake_polarity = CYCFG_BT_DEV_WAKE_POLARITY,
            .host_wake_polarity = CYCFG_BT_HOST_WAKE_IRQ_EVENT
            #else /* Low power is disabled in the LPA, disable low power */
            .sleep_mode_enabled = false
            #endif
            #else /* BT Power control is disabled in the LPA – default to BSP low power configuration */
            .sleep_mode_enabled = true,
            .device_wakeup_pin = CYBSP_BT_DEVICE_WAKE,
            .host_wakeup_pin = CYBSP_BT_HOST_WAKE,
            .device_wake_polarity = CYBT_WAKE_ACTIVE_LOW,
            .host_wake_polarity = CYBT_WAKE_ACTIVE_LOW
            #endif
        }
    },

    .task_mem_pool_size    = 2048
};

Inside of Visual Studio Code, create bluetoothManager.h.  Remember this is the Bluetooth Stack Management Callback

#pragma once
#include "wiced_bt_stack.h"
#include "wiced_bt_dev.h"
wiced_result_t app_bt_management_callback(wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data);

Inside of Visual Studio code, create bluetoothManager.c.  This function does a whole lotta nothin… except saying that things got started.

#include <stdio.h>
#include <stdlib.h>
#include "cybsp.h"
#include "FreeRTOS.h"
#include "bluetoothManager.h"
#include "wiced_bt_stack.h"
#include "wiced_bt_dev.h"
#include "wiced_bt_trace.h"
/**************************************************************************************************
* Function Name: app_bt_management_callback()
***************************************************************************************************
* Summary:
*   This is a Bluetooth stack event handler function to receive management events from
*   the BLE stack and process as per the application.
*
* Parameters:
*   wiced_bt_management_evt_t event             : BLE event code of one byte length
*   wiced_bt_management_evt_data_t *p_event_data: Pointer to BLE management event structures
*
* Return:
*  wiced_result_t: Error code from WICED_RESULT_LIST or BT_RESULT_LIST
*
*************************************************************************************************/
wiced_result_t app_bt_management_callback(wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data)
{
wiced_result_t result = WICED_BT_SUCCESS;
switch (event)
{
case BTM_ENABLED_EVT:
if (WICED_BT_SUCCESS == p_event_data->enabled.status)
{
printf("Started BT Stack Succesfully\n");
}
else
{
printf("Error enabling BTM_ENABLED_EVENT\n");
}
break;
default:
printf("Unhandled Bluetooth Management Event: 0x%x\n", event);
break;
}
return result;
}

Next, update main.c with the required includes.

#include "bluetoothManager.h"
#include "cycfg_bt_settings.h"
#include "bt_platform_cfg_settings.h"

Then update main.c to start the stack

    cybt_platform_config_init(&bt_platform_cfg_settings);
wiced_bt_stack_init (app_bt_management_callback, &wiced_bt_cfg_settings);

Now build and program it, remember “make -j build” and “make program”.  Look, we have a functioning stack with the two bluetooth thread running.

In the next article Ill finally get around to building the Bluetooth Scanner.

AnyCloud – Wireless Connection Manager (Part 2)

Summary

Part 2 of the discussion of using the Infineon (Cypress) PSoC 6 with a CYW4343W and the AnyCloud Connection Manager with Modus Toolbox.  The AnyCloud Connection Manager is an RTOS thread that lets you manage a connection to a WiFi network.  It knows how to scan for networks, attach, detach etc. and was recently released for use with PSoC6 and 43xxx WiFi combos.

The Story

In the last article I walked you through creating a project using the wireless connection manager (WCM) which is one of the libraries that is part of the Infineon/Cypress AnyCloud SDK.  I introduced the wifi-mw-core, wifi-connection-manager and ntshell libraries.  In this article I will update the program to include commands to

  • connect (to an Access Point)
  • disconnect (from an Access Point)
  • print (mac address and ip address)

Add the Connect

I want to add a command that will let me issue a command line like

  • connect SSID (if it doesn’t have a passphrase)
  • connect SSID passphrase

In order to connect to an Access Point you need to call the WCM API, cy_wcm_connect_ap.  Here is the function prototype:

cy_rslt_t cy_wcm_connect_ap(const cy_wcm_connect_params_t *connect_params, cy_wcm_ip_address_t *ip_addr)

This function requires that you give it two arguments

  1. A pointer for a place to store the IP address (that comes from the DHCP server)
  2. A pointer to a structure of connection parameters.  That structure is as follows:
typedef struct
{
cy_wcm_ap_credentials_t  ap_credentials;       /**< Access point credentials */
cy_wcm_mac_t             BSSID;                /**< Specifies the MAC address of Access Point (optional) */
cy_wcm_ip_setting_t      *static_ip_settings;  /**< Specifies the static IP settings of the device (optional) */
cy_wcm_wifi_band_t       band;                 /**< Specifies the Radio band to be connected (optional) */
} cy_wcm_connect_params_t;

Typically you would setup the “ap_credentials” part of the structure (unless you happen to know the MAC address of the AP you want to connect to).  Those credentials include the SSID and password as well as the security (WPA2 PSK etc…)

typedef struct
{
cy_wcm_ssid_t        SSID;                /**< SSID of the Wi-Fi network to join, SSID should be a null terminated string. */
cy_wcm_passphrase_t  password;            /**< Password needed to join the AP, password should be a null terminated string. */
cy_wcm_security_t    security;            /**< Wi-Fi Security. @see cy_wcm_security_t. */
} cy_wcm_ap_credentials_t;

Security is an enumeration of possible security types.

typedef enum
{
WHD_SECURITY_OPEN             = 0,                                                                 /**< Open security                                         */
WHD_SECURITY_WEP_PSK          = WEP_ENABLED,                                                       /**< WEP PSK Security with open authentication             */
WHD_SECURITY_WEP_SHARED       = (WEP_ENABLED | SHARED_ENABLED),                                    /**< WEP PSK Security with shared authentication           */
WHD_SECURITY_WPA_TKIP_PSK     = (WPA_SECURITY | TKIP_ENABLED),                                     /**< WPA PSK Security with TKIP                            */
WHD_SECURITY_WPA_AES_PSK      = (WPA_SECURITY | AES_ENABLED),                                      /**< WPA PSK Security with AES                             */
WHD_SECURITY_WPA_MIXED_PSK    = (WPA_SECURITY | AES_ENABLED | TKIP_ENABLED),                       /**< WPA PSK Security with AES & TKIP                      */
WHD_SECURITY_WPA2_AES_PSK     = (WPA2_SECURITY | AES_ENABLED),                                     /**< WPA2 PSK Security with AES                            */
WHD_SECURITY_WPA2_TKIP_PSK    = (WPA2_SECURITY | TKIP_ENABLED),                                    /**< WPA2 PSK Security with TKIP                           */
WHD_SECURITY_WPA2_MIXED_PSK   = (WPA2_SECURITY | AES_ENABLED | TKIP_ENABLED),                      /**< WPA2 PSK Security with AES & TKIP                     */
WHD_SECURITY_WPA2_FBT_PSK     = (WPA2_SECURITY | AES_ENABLED | FBT_ENABLED),                       /**< WPA2 FBT PSK Security with AES & TKIP */
WHD_SECURITY_WPA3_SAE         = (WPA3_SECURITY | AES_ENABLED),                                     /**< WPA3 Security with AES */
WHD_SECURITY_WPA3_WPA2_PSK    = (WPA3_SECURITY | WPA2_SECURITY | AES_ENABLED),                     /**< WPA3 WPA2 PSK Security with AES */
WHD_SECURITY_WPA_TKIP_ENT     = (ENTERPRISE_ENABLED | WPA_SECURITY | TKIP_ENABLED),                /**< WPA Enterprise Security with TKIP                     */
WHD_SECURITY_WPA_AES_ENT      = (ENTERPRISE_ENABLED | WPA_SECURITY | AES_ENABLED),                 /**< WPA Enterprise Security with AES                      */
WHD_SECURITY_WPA_MIXED_ENT    = (ENTERPRISE_ENABLED | WPA_SECURITY | AES_ENABLED | TKIP_ENABLED),  /**< WPA Enterprise Security with AES & TKIP               */
WHD_SECURITY_WPA2_TKIP_ENT    = (ENTERPRISE_ENABLED | WPA2_SECURITY | TKIP_ENABLED),               /**< WPA2 Enterprise Security with TKIP                    */
WHD_SECURITY_WPA2_AES_ENT     = (ENTERPRISE_ENABLED | WPA2_SECURITY | AES_ENABLED),                /**< WPA2 Enterprise Security with AES                     */
WHD_SECURITY_WPA2_MIXED_ENT   = (ENTERPRISE_ENABLED | WPA2_SECURITY | AES_ENABLED | TKIP_ENABLED), /**< WPA2 Enterprise Security with AES & TKIP              */
WHD_SECURITY_WPA2_FBT_ENT     = (ENTERPRISE_ENABLED | WPA2_SECURITY | AES_ENABLED | FBT_ENABLED),  /**< WPA2 Enterprise Security with AES & FBT               */
WHD_SECURITY_IBSS_OPEN        = (IBSS_ENABLED),                                                    /**< Open security on IBSS ad-hoc network                  */
WHD_SECURITY_WPS_SECURE       = AES_ENABLED,                                                       /**< WPS with AES security                                 */
WHD_SECURITY_UNKNOWN          = -1,                                                                /**< May be returned by scan function if security is unknown. Do not pass this to the join function! */
WHD_SECURITY_FORCE_32_BIT     = 0x7fffffff                                                         /**< Exists only to force whd_security_t type to 32 bits */
} whd_security_t;

Having to know the security of the AP is a total pain in the neck.  Where do you find the security from?  It turns out that when an AP beacons, the security of that SSID is one of the things that is broadcast.  What this means is that my program will need to

  1. When the connect command is called it should scan for the SSID that is part of the connect command & wait
  2. When the scan finds that SSID it will put the security type into the correct datastructure
  3. Then call the connect.

The way that I will do this is to

  1. Build a filter (that looks only for the user specified SSID)
  2. Provides a pointer for a place to store the security type.

I use the cy_wcm_scan function to do this.  Here is the function prototype:

cy_rslt_t cy_wcm_start_scan(cy_wcm_scan_result_callback_t callback, void *user_data, cy_wcm_scan_filter_t *scan_filter)

The scan filter is just a structure that specified

  1. A mode (which type of filter you want)
  2. The specific thing that you are looking for.
typedef struct
{
cy_wcm_scan_filter_type_t      mode;        /**< Scan filter mode */
union
{
cy_wcm_ssid_t              SSID;        /**< Service Set Identification */
cy_wcm_mac_t               BSSID;       /**< MAC address of Access Point */
cy_wcm_wifi_band_t         band;        /**< Radio band */
cy_wcm_scan_rssi_range_t   rssi_range;  /**< RSSI range */
} param;                                    /**< Scan filter mode specific paramter */
} cy_wcm_scan_filter_t;

The mode is simply an enumeration of the types of filters:

typedef enum
{
CY_WCM_SCAN_FILTER_TYPE_SSID = 0,   /**< Denotes SSID based scan filtering */
CY_WCM_SCAN_FILTER_TYPE_MAC,        /**< Denotes MAC  based scan filtering */
CY_WCM_SCAN_FILTER_TYPE_BAND,       /**< Denotes BAND based scan filtering */
CY_WCM_SCAN_FILTER_TYPE_RSSI,       /**< Denotes RSSI based scan filtering */
}cy_wcm_scan_filter_type_t;

What I want to do is start the scan and then wait for a semaphore.  To do this I will create a semaphore variable at the top of the netTask.c

SemaphoreHandle_t scanApSempahore = NULL;

Inside of the switch I will

  1. Create a connection parameters structure (line 226-227)
  2. setup the scan filter (line 231-232)
  3. create the semaphore (line 235)
  4. run the scan (line 236)
  5. wait for the semaphore to be set or timeout (line 239) notice that I hardcoded it to 10 seconds
				cy_wcm_connect_params_t connect_params;
memset(&connect_params, 0, sizeof(cy_wcm_connect_params_t));
// setup scan filter - In order to connect to an SSID you need to know the security type
// To find the security I scan for JUST that SSID which will tell me the security type
scanFilter.mode = CY_WCM_SCAN_FILTER_TYPE_SSID;
strcpy((char *)scanFilter.param.SSID,(char *)msg.val0);
// The scan callback will either 1) unlock the semaphore or 2) timeout (meaning it didnt find it)
scanApSempahore = xSemaphoreCreateBinary();
cy_wcm_start_scan(findApCallback,&connect_params.ap_credentials.security,&scanFilter);
// The semaphore will return pdFALSE if it TIMES out or pdTrue IF it got unlocked by the scan
if(xSemaphoreTake( scanApSempahore, pdMS_TO_TICKS(10000)) == pdTRUE)

In the scan callback I will check to see if I have real data (in other words the scan is not complete).  In the setup above I made the user data be a pointer to the place to store the security.  On line 54 I will store the security type that came back from the scan in the place pointed to by the user data pointer.  Then I will stop the scan and give the semaphore.

// This callback is used to find a specific SSID and then store the security type into the user data
// When I want to connect it will scan with a "filter" and the user data will be a pointer to the
// place to store the security
void findApCallback( cy_wcm_scan_result_t *result_ptr, void *user_data, cy_wcm_scan_status_t status )
{
if(status == CY_WCM_SCAN_INCOMPLETE)
{
whd_security_t *mySecurity = (whd_security_t *)user_data;
*mySecurity = result_ptr->security;
cy_wcm_stop_scan();
xSemaphoreGive(scanApSempahore);
}
}

Now back in the switch statement you can actually connect because you know the security type (line 244)  The else clause on line 253 handles the case where the timeout of the semaphore occurred, meaning that the scan didn’t find the AP.

				// The semaphore will return pdFALSE if it TIMES out or pdTrue IF it got unlocked by the scan
if(xSemaphoreTake( scanApSempahore, pdMS_TO_TICKS(10000)) == pdTRUE)
{
strcpy((char *)connect_params.ap_credentials.SSID,(char *)msg.val0);
strcpy((char *)connect_params.ap_credentials.password,(char *)msg.val1);
result = cy_wcm_connect_ap(&connect_params,&ip_addr);
if(result == CY_RSLT_SUCCESS)
printf("Connect Succeeded SSID=%s\n",(char *)msg.val0);
else
{
printf("Connect to %s failed\n",(char *)msg.val0);
}	
}
else
{
printf("Scan semaphore failed - couldnt find AP\n");
}
free((void *)msg.val0); // Free the SSID and PW that was passed by the caller
free((void *)msg.val1);
}
break;

With all of the connection work done, you can add the scan command to “usrcmd.c”.  It just looks at the number of arguments (either 2 or 3), then sets up the message to send to the network task, the queues the message.

static int usrcmd_connect(int argc, char **argv)
{
networkQueueMsg_t msg;
if(argc == 2)
{
msg.val0 = (uint32_t)malloc(strlen(argv[1])+1);
msg.val1 = (uint32_t)malloc(sizeof(""));
strcpy((char *)msg.val0,argv[1]);
strcpy((char *)msg.val1,"");
msg.cmd = net_connect;
xQueueSend(networkQueue,(const void *)&msg,portMAX_DELAY);
}
if(argc == 3)
{
msg.val0 = (uint32_t)malloc(strlen(argv[1])+1);
msg.val1 = (uint32_t)malloc(strlen(argv[2])+1);
strcpy((char *)msg.val0,argv[1]);
strcpy((char *)msg.val1,argv[2]);
msg.cmd = net_connect;
xQueueSend(networkQueue,(const void *)&msg,portMAX_DELAY);
}
return 0;
}

Add the Disconnect Command

The disconnect command is trivial.  Just call the disconnect api.

			case net_disconnect:
cy_wcm_disconnect_ap();
break;

Which you also need to add to the usercmd.c

static int usrcmd_disconnect(int argc, char **argv)
{
networkQueueMsg_t msg;
msg.cmd = net_disconnect;
xQueueSend(networkQueue,(const void *)&msg,portMAX_DELAY);
return 0;
}

Add the Print Command

The print command will have two optional parameters, IP (to print the current IP address) and MAC (to print our MAC address).  The first command is print ip.

			case net_printip:
result = cy_wcm_get_ip_addr(CY_WCM_INTERFACE_TYPE_STA,&ip_addr,1);
if(result == CY_RSLT_SUCCESS)
{
printf("IP Address=");
printIp(&ip_addr);
printf("\n");
}
else if(result == CY_RSLT_WCM_NETWORK_DOWN)
printf("Network disconnected\n");
else 
printf("IP Address call return unknown %d\n",(int)result);
break;

The MAC address command is also simple:

			case net_printmac:
result = cy_wcm_get_mac_addr(CY_WCM_INTERFACE_TYPE_STA,&mac_addr,1);
if(result == CY_RSLT_SUCCESS)
{
printf("MAC Address =");
printMac(mac_addr);
printf("\n");
}
else
printf("MAC Address = Unknown\n");
break;
}

And you need to add the print command to usrcmd.c

static int usrcmd_print(int argc, char **argv)
{
networkQueueMsg_t msg;
if(argc == 2 && strcmp(argv[1],"ip")==0)
{
msg.cmd = net_printip;
xQueueSend(networkQueue,(const void *)&msg,portMAX_DELAY);
}
if(argc == 2 && strcmp(argv[1],"mac")==0)
{
msg.cmd = net_printmac;
xQueueSend(networkQueue,(const void *)&msg,portMAX_DELAY);
}
return 0;
}

All of this code is available on github at

  • git@github.com:iotexpert/wcm_example
  • https://github.com/iotexpert/wcm_example

I2C Detect with PSoC 6

Summary

In this article I explain how to use a PSoC 6 SCB to implement I2C Detect.

Recently,  I wrote about using the Raspberry PI I2C bus master to talk to a PSoC 4 I2C Slave.  In that project I used a program on the Raspberry Pi called “I2CDetect” which probes the I2C bus and prints out devices that are attached.  Here is what the output looks like:

pi@iotexpertpi:~/pyGetData $ i2cdetect -y 1
0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- 08 -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- --                         
pi@iotexpertpi:~/pyGetData $ 

You can do this same thing by using the bridge control panel (which comes as part of PSoC Creator).  I have used this program a bunch of times on this blog and you can search for all of those here.

But how does it work?  Simple, it uses the I2C bus master to iterate through all of the addresses 0-0x7F and

  • Send a start
  • Send the address
  • Send a write
  • If you get ACK print out the address
  • If you get a NAK print out —
  • Send a stop

You can easily do this using the PSoC 6 (or 4) Serial Communication Block.  Here is an implementation in Modus Toolbox 1.1 where I

  1. Create the project and configure the middleware
  2. Implement probe
  3. Implement the main loop
  4. Test

Create the Project, Configure the Hardware and Middleware

Start by creating a new project.  In this case I have a CY8CKIT_062_WIFI_BT.  But this will work on any PSoC6s.

I just start with the empty project.

Click Finish to make the project.

Double click on the “design.modus” or click “Configure Device” from the quick panel.

Here is the design.modus

When the configurator starts you need to enable the SCB that is connected to the Kitprog bridge.  You can figure this out by looking on the back of your development kit where there is a little table.  In the picture below you can see that the UART is connected to P5.0 and P5.1

Which SCB is P5.0/P5.1 connected to?  The answer is SCB5.  But how do you figure that out?  Click on the Pins table.  Then select P5[0] and then Digital In/Out and you can see that the SCB 5 UART RX is attached to that pin.

Cancel that and go to SCB 5.  Enable it.  Select the UART personality.  Give it the name “STDIO”.  Pick a clock divider (in this case I picked 1… but it doesn’t matter as the configurator will pick the right divide value).  Then pick the Rx/Tx to be P5[0] and P5[1]

Next you need to turn on the I2C Master.  On my board the SCB bus that I want to use is connected to P6[0] P6[1].  The bus I want is the standard Arduino I2C pins.  I can see that from the back of the development kit (just like above).  These pins are connected to SCB3 (which I figured out just like I did with the UART).

Enable SCB3. Select the I2C personality.  Give it the name I2CBUS. Select Master. Make it 400kbs.  Assign a clock divider (in this case 0).  Assign the SCL and SDA pins to P6[0] and P6[1]

Hit save.

For this example I want to be able to use printf.  So I right click on the “Select Middleware” from the quick panel.

Then I add “Retarget I/O”.

Once that is done you will have “stdio_user.h” and “stdio_user.c” in your Source directory:

In order to turn on printf you need to modify stdio_user.h so that it uses the right SCB for printing.  But what is that SCB?  Simple we called it “STDIO” in the configurator.  Here is the change you need to make:

#include "cy_device_headers.h"
#include "cycfg.h"
/* Must remain uncommented to use this utility */
#define IO_STDOUT_ENABLE
#define IO_STDIN_ENABLE
#define IO_STDOUT_UART      STDIO_HW
#define IO_STDIN_UART       STDIO_HW

Edit main.c.  Add a function called “probe” which will

  1. Print a header (line 15-19)
  2. Iterate through all of the addresses (line 22)
  3. If you have hit the end of a line setup the next line (lines 24-25)
  4. Send a start and write (line 27)
  5. If you get a CY_SCB_SUCCESS then print the address (line 30)
  6. Otherwise print a “–” (line 34)
// Print the probe table
void probe()
{
uint32_t rval;
// Setup the screen and print the header
printf("\n\n   ");
for(unsigned int i=0;i<0x10;i++)
{
printf("%02X ",i);
}
// Iterate through the address starting at 0x00
for(uint32_t i2caddress=0;i2caddress<0x80;i2caddress++)
{
if(i2caddress % 0x10 == 0 )
printf("\n%02X ",(unsigned int)i2caddress);
rval = Cy_SCB_I2C_MasterSendStart(I2CBUS_HW,i2caddress,CY_SCB_I2C_WRITE_XFER,10,&I2CBUS_context);
if(rval == CY_SCB_I2C_SUCCESS ) // If you get ACK then print the address
{
printf("%02X ",(unsigned int)i2caddress);
}
else //  Otherwise print a --
{
printf("-- ");
}
Cy_SCB_I2C_MasterSendStop(I2CBUS_HW,0,&I2CBUS_context);
}
printf("\n");
}

For all of this to work you need to have two context global variables which are used by PDL to save state.

cy_stc_scb_uart_context_t STDIO_context;
cy_stc_scb_i2c_context_t I2CBUS_context;

Create a main function to:

  • initialize the two SCBs 45-50
  • The API call setvbuf on line 47 just turns off buffering on stdin so that every character will come directly to getc
  • print the header (line 54-56)
  • the clear screen line just send the VT100 escape sequence to clear the screen and go home.  Almost all terminal programs are essentially VT100 emulators.
  • run the probe one time (line 57)
  • go into an infinite loop looking for key presses (line 59-61)
  • if they press ‘p’ then call the probe function (line 64)
  • if they press ‘?’ then printout help (line 69)
int main(void)
{
/* Set up the device based on configurator selections */
init_cycfg_all();
Cy_SCB_UART_Init(STDIO_HW,&STDIO_config,&STDIO_context);
Cy_SCB_UART_Enable(STDIO_HW);
setvbuf( stdin, NULL, _IONBF, 0 ); // Turn off stdin buffering
Cy_SCB_I2C_Init(I2CBUS_HW,&I2CBUS_config,&I2CBUS_context);
Cy_SCB_I2C_Enable(I2CBUS_HW);
__enable_irq();
printf("\033[2J\033[H"); // clear the screen
printf("I2C Detect\n");
printf("Press p for probe, ? for help\n");
probe(); // Do an initial probe
while(1)
{
char c = getchar();
switch(c)
{
case 'p':
probe();
break;
case '?':
printf("------------------\n");
printf("Command\n");
printf("p\tProbe\n");
printf("?\tHelp\n");
break;
}
}
}

Once I program this I get a nice output.  Notice that these are all 7-bit addresses.

If I connect a logic analyzer you can see the bus behavior.  Start with a bunch of 0 – nak, 1-nak ….

until finally it hits 3C when it get an ACK

Here is the whole program

#include "cy_device_headers.h"
#include "cycfg.h"
#include <stdio.h>
cy_stc_scb_uart_context_t STDIO_context;
cy_stc_scb_i2c_context_t I2CBUS_context;
// Print the probe table
void probe()
{
uint32_t rval;
// Setup the screen and print the header
printf("\n\n   ");
for(unsigned int i=0;i<0x10;i++)
{
printf("%02X ",i);
}
// Iterate through the address starting at 0x00
for(uint32_t i2caddress=0;i2caddress<0x80;i2caddress++)
{
if(i2caddress % 0x10 == 0 )
printf("\n%02X ",(unsigned int)i2caddress);
rval = Cy_SCB_I2C_MasterSendStart(I2CBUS_HW,i2caddress,CY_SCB_I2C_WRITE_XFER,10,&I2CBUS_context);
if(rval == CY_SCB_I2C_SUCCESS ) // If you get ACK then print the address
{
printf("%02X ",(unsigned int)i2caddress);
}
else //  Otherwise print a --
{
printf("-- ");
}
Cy_SCB_I2C_MasterSendStop(I2CBUS_HW,0,&I2CBUS_context);
}
printf("\n");
}
int main(void)
{
/* Set up the device based on configurator selections */
init_cycfg_all();
Cy_SCB_UART_Init(STDIO_HW,&STDIO_config,&STDIO_context);
Cy_SCB_UART_Enable(STDIO_HW);
setvbuf( stdin, NULL, _IONBF, 0 ); // Turn off stdin buffering
Cy_SCB_I2C_Init(I2CBUS_HW,&I2CBUS_config,&I2CBUS_context);
Cy_SCB_I2C_Enable(I2CBUS_HW);
__enable_irq();
printf("\033[2J\033[H"); // clear the screen
printf("I2C Detect\n");
printf("Press p for probe, ? for help\n");
probe(); // Do an initial probe
while(1)
{
char c = getchar();
switch(c)
{
case 'p':
probe();
break;
case '?':
printf("------------------\n");
printf("Command\n");
printf("p\tProbe\n");
printf("?\tHelp\n");
break;
}
}
}

 

Mouser PSoC 6-WiFi-BT L8: Integrate WiFi and AWS Into the Game

Designing low-power, cloud-connected IoT devices with PSoC® 6 MCU’s and WICED® Wi-Fi/Bluetooth

Summary

In this lesson we will move the subscriber app functionality into the main GameBle project (now called GameBleAws).  In order to do this, you need to turn the subscriber into a thread, and fix it so that messages that are sent to the PADDLE topic get turned into messages that can be sent to the paddleQueue.

To implement this lesson I will follow these steps:

  1. Create a New Project starting from L6GameBle
  2. Copy over subscriber.c and wifi_config_dct.h
  3. Update the Makefile
  4. Create subscriber.h
  5. Update main.c
  6. Update subscriber.c
  7. Test

Create a New Project

Copy and paste the L6GameBle project into a new project called L8GameBleAws using Copy/Paste

Create a new Make target for the GameBleAws project

Copy subscriber.c & wifi_config_dct.h

Use copy/paste to make a copy of the subscriber application and paste it into the GameBleAws project.  Once done your folder should look like this:

Update the Makefile

NAME := App_WStudio_L8GameBleAws
$(NAME)_SOURCES := main.c \
CapSenseThread.c \
GameThread.c \
cy_tft_display.c \
GoBleThread.c \
GoBle_db.c \
wiced_bt_cfg.c \
subscriber.c
$(NAME)_COMPONENTS := graphics/ugui \
libraries/drivers/bluetooth/low_energy \
protocols/AWS
WIFI_CONFIG_DCT_H := wifi_config_dct.h
$(NAME)_RESOURCES  := apps/aws/iot/rootca.cer \
apps/aws/iot/subscriber/client.cer \
apps/aws/iot/subscriber/privkey.cer
# To support Low memory platforms, disabling components which are not required
GLOBAL_DEFINES += WICED_CONFIG_DISABLE_SSL_SERVER \
WICED_CONFIG_DISABLE_DTLS \
WICED_CONFIG_DISABLE_ENTERPRISE_SECURITY \
WICED_CONFIG_DISABLE_DES \
WICED_CONFIG_DISABLE_ADVANCED_SECURITY_CURVES

Create subscriber.h

In order for the main.c to know about the awsThread (which is the former application_start of subscriber.c) you should create a file called subscriber.h.  Then you should define the awsThread function to match the wiced_thread_t function prototype (just a function that takes a wiced_thread_arg and returns void).

#pragma once
extern void awsThread( wiced_thread_arg_t arg );

Update main.c

To integrate the awsThread thread into your main project you need to add the “subscriber.h” to the includes:

#include "GameThread.h"
#include "GoBleThread.h"
#include "CapSenseThread.h"
#include "subscriber.h"
#include "wiced.h"

Add a new variable to hold the awsThreadHandle.

wiced_thread_t awsThreadHandle;

Finally you should launch the AWS thread by creating it with wiced_rtos_create_thread.

void application_start( )
{
wiced_init( );
wiced_rtos_init_queue(&paddleQueue,"paddleQueue",sizeof(game_msg_t),10);
wiced_rtos_create_thread(&blinkThreadHandle,7,"Blink Thread",pdlBlinkThread,500,0);
wiced_rtos_create_thread(&capsenseThreadHandle,7,"CapSense Thread",capSenseThread,1024,0);
wiced_rtos_create_thread(&gameThreadHandle,7,"game Thread",gameThread,4096,0);
GoBleThread_start();
wiced_rtos_create_thread(&awsThreadHandle,7,"AWS Thread",awsThread,4096,0);
}

Update subscriber.c

In order for subscriber.c to be useful you need to fix the includes, send the messages from the PADDLE topic to the game thread, and turn application_start into a thread.  Start by fixing the includes (just like we did in the BLE Example in Lesson 6)

#include "SystemGlobal.h"
#include "GameThread.h"

When you get a message to the PADDLE topic, you should parse it, then send a message to the game thread to move the paddle.  You do this exactly the same way as you did in the BLE project.  Notice that I protect the game thread by making sure it send a value less than 100.

        case WICED_AWS_EVENT_PAYLOAD_RECEIVED:
{
uint32_t val;
WPRINT_APP_INFO( ("[Application/AWS] Payload Received[ Topic: %.*s ]:\n", (int)data->message.topic_length, data->message.topic ) );
if(strncmp(WICED_TOPIC,(const char *)data->message.topic,strlen(WICED_TOPIC)) == 0 && data->message.data_length < 4)
{
sscanf((const char *)data->message.data,"%d",(int *)&val);
if(val>100)
val = 100;
WPRINT_APP_INFO(("Val = %d\n",(int)val));
game_msg_t msg;
msg.evt = MSG_POSITION;
msg.val = val;
wiced_rtos_push_to_queue(&paddleQueue,&msg,0);
}
}
break;

Test

I don’t really have a good program (like the GoBle) to test moving the paddle live.  But you can see that when the game is over, you can still move the paddle using AWS console.  In the screen shot below you can see that I moved the paddle to position 0.  And you can see that the BLE started at the same time as AWS.  Score.

Mouser PSoC 6-WiFi-BT L7 : Implement WiFi and AWS

Designing low-power, cloud-connected IoT devices with PSoC® 6 MCU’s and WICED® Wi-Fi/Bluetooth

Summary

In this lesson I am going to update one of the predefined application which we deliver as part of WICED Studio which knows how to connect to the AWS IoT Cloud to work on my network.  This will demonstrate WiFi and MQTT.  I will also fix the application so that it knows about a new MQTT Topic called “PADDLE” which will be used to send messages to move the game paddle.

To implement this project I will:

  1. Copy the subscriber from demo/aws/iot/pub_sub/subscriber
  2. Setup a “thing” on AWS and download the certificates
  3. Update the certificates in the WICED installation
  4. Update the project with my AWS configuration
  5. Test
  6. Update the project to be compatible with the Game
  7. Test

Copy Subscriber & Fix the Makefile

The first thing that I will do is copy/paste the subscriber application which can be found at demo/aws/iot/pub_sub/subscriber into my folder.  I will also rename the project to L7subscriber. Once that is done it should look like this:

Then you need to edit the Makefile to update the name of the project.

NAME := App_WStudio_L7subscriber

Go to Amazon.com and Create a “thing”

In order to connect to the AWS cloud you need to create a “thing”.  Go to the AWS console and click “Create”

We are just going to create one thing.  So, click “Create a single thing”

Give it a name, in this case Mouser.

AWS has device level security which is implemented with RSA certificates for each device.  So,  you need to let AWS create a certificate for you.

Once that is done download the device certificate and the two keys.  You need to 100% make sure you do this now, because you wont get another chance. I’m also going to activate the certificate once I have the certificate and keys.

Now attach a policy to your thing.  I already have the “ww101_policy” setup.

The policy looks like this.  Basically, things are wide open.

Update the Certificates

The last thing that you need is the most recent AWS certificate.  WICED expects that you use the RSA2048 bit key.

Now that you have the four security documents., you need to integrate them into your WICED installation.  To do this, change directories to ~/Documents/WICED-Studio-6.2/43xxx_Wi-Fi/resources/apps/aws/iot  Then copy the files, and then make symbolic links.  If you are not on a Mac or Linux then just copy the files and rename them appropriately.

Update the Project

AWS creates a virtual machine and runs an MQTT server on that machine.  You can find out the DNS name of that machine on the settings screen.  Here you can see my endpoint.  You will need to configure the WICED project to talk to your server.

You need to change the actual endpoint of your MQTT server in the AWS cloud on line 119

static wiced_aws_endpoint_info_t my_subscriber_aws_iot_endpoint = {
.transport           = WICED_AWS_TRANSPORT_MQTT_NATIVE,
.uri                 = "amk6m51qrxr2u-ats.iot.us-east-1.amazonaws.com",
.peer_common_name    = NULL,
.ip_addr             = {0},
.port                = WICED_AWS_IOT_DEFAULT_MQTT_PORT,
.root_ca_certificate = NULL,
.root_ca_length      = 0,
};

In the file wifi_config_dct.h you will need to change the CLIENT_AP_SSID and CLIENT_AP_PASSPHRASE for your network

/* This is the default AP the device will connect to (as a client)*/
#define CLIENT_AP_SSID       "WW101WPA"
#define CLIENT_AP_PASSPHRASE "yourpassword"
#define CLIENT_AP_BSS_TYPE   WICED_BSS_TYPE_INFRASTRUCTURE
#define CLIENT_AP_SECURITY   WICED_SECURITY_WPA2_MIXED_PSK
#define CLIENT_AP_CHANNEL    1
#define CLIENT_AP_BAND       WICED_802_11_BAND_2_4GHZ

Test

In order to test the project you will need to create a make target and program your development kit.

Once that is done you can go to the Amazon.com test console and send MQTT messages to the correct topic.

Here you can see the project attached to my network.  And successfully received the LIGHT ON message.

Update the Project for the Game

We know that the game doesn’t care about the LIGHT topic so, let’s change it to PADDLE.

#define WICED_TOPIC                                 "PADDLE"

And let’s assume that messages to the paddle topic are ASCII numbers <100.  So, we can parse the message and print it out.  Notice that I used sscanf to parse the message and we all know that is super dangerous.

        case WICED_AWS_EVENT_PAYLOAD_RECEIVED:
{
char buff[10];
uint32_t val;
WPRINT_APP_INFO( ("[Application/AWS] Payload Received[ Topic: %.*s ]:\n", (int)data->message.topic_length, data->message.topic ) );
if(strncmp(WICED_TOPIC,data->message.topic,strlen(WICED_TOPIC)) == 0 && data->message.data_length < 4)
{
sscanf(data->message.data,"%d",&val);
WPRINT_APP_INFO(("Val = %d\n",val));
}
}
break;

Test

After making those updates let’s program the whole shooting match again.  Then test by sending some messages to the PADDLE topic.

It’s good.  Things are working.

Mouser PSoC6-WiFi-BT L6 : Integrate GoBle Bluetooth into the Game

Designing low-power, cloud-connected IoT devices with PSoC® 6 MCU’s and WICED® Wi-Fi/Bluetooth

Summary

At this point we have a working BLE Remote Control and a working Game.  In this lesson I’ll merge the two projects together so that the GoBle remote control will be able to control the game paddle.  It will do this by creating messages (just like the CapSense messages) and sending them to the Game thread via the paddleQueue.  And it will send “Button0” messages when “Button A” is pressed.

To implement this lesson I will follow these steps:

  1. Copy everything into a new project
  2. Modify the Makefile
  3. Modify main.c
  4. Create a new make target
  5. Test it all to make sure things are still working
  6. Modify GoBleThread.c
  7. Program and Test

Copy L4Game into a new project L6GameBle

Use “copy” and “paste” to create a new project, when you paste give it the name “L6GameBle” (there is an error in the screenshot)

Copy the files GoBle_db.c/h, GoBleThread.c/h, and wiced_bt_cfg.c from the GoBle project into your new GameBle project.  After that is done your project should look like this:

Modify the Makefile

  1. Change the name of the App to “App_WStudio_L6GameBle”
  2. Add the new source files
  3. Add the BLE Library “libraries/drivers/bluetooth/low_energy”
NAME := App_WStudio_L6GameBle
$(NAME)_SOURCES := main.c \
CapSenseThread.c \
GameThread.c \
cy_tft_display.c \
GoBleThread.c \
GoBle_db.c \
wiced_bt_cfg.c
$(NAME)_COMPONENTS := graphics/ugui \
libraries/drivers/bluetooth/low_energy

Modify main.c

Add the include for the GeBleThread.

#include "GameThread.h"
#include "GoBleThread.h"
#include "CapSenseThread.h"
#include "wiced.h"

In the application_start function add a call GoBleThread_start() to get the GoBle thread going

void application_start( )
{
wiced_init( );
wiced_rtos_init_queue(&paddleQueue,"paddleQueue",sizeof(game_msg_t),10);
wiced_rtos_create_thread(&blinkThreadHandle,7,"Blink Thread",pdlBlinkThread,500,0);
wiced_rtos_create_thread(&capSenseThreadHandle,7,"CapSense Thread",capSenseThread,1024,0);
wiced_rtos_create_thread(&gameThreadHandle,7,"game Thread",gameThread,4096,0);
GoBleThread_start();
}

Create a new make target

Test it all to make sure things are still working

Run the make target and make sure that the game still plays and that you can get remote control messages.

Modify GoBleThread.c

Add the includes for the GameThread (to get access to the game message structure) and SystemGlobal (to get access to the queue)

#include "GameThread.h"
#include "SystemGlobal.h"

I don’t need (or want) the button/slider printout information.  So I will delete the old button code from goble_event_handler. (delete this stuff)

            WPRINT_APP_INFO(("# Buttons = %d ButtonMask=%02X Slider x=%02X Slider Y=%02X Raw=",(int)numButtons,(unsigned int)buttonMask,(unsigned int)sliderX,(unsigned int)sliderY));
for(int i=0;i<p_attr_req->data.write_req.val_len;i++)
{
WPRINT_APP_INFO(("%02X ",p_attr_req->data.write_req.p_val[i]));
}
WPRINT_APP_INFO(("\n"));

Now, update the code to send the slider and button information to the GameThread (via the paddleQueue).  You may have noticed that the slider on GoBle gives you 0->0xFF and the direction is the inverse from the game we setup.  So, I will scale the value to 100 and invert it so that the controller moves the paddle the right way on line 143.  The message format is exactly the same as what we setup for the CapSense.  This means the CapSense slider works at the same time as the GoBle controller.

   case GATT_ATTRIBUTE_REQUEST_EVT:
p_attr_req = &p_event_data->attribute_request;
if( p_attr_req->request_type == GATTS_REQ_TYPE_WRITE  && p_attr_req->data.handle == HDLC_GOBLE_SERIALPORTID_VALUE)
{
uint32_t numButtons = p_attr_req->data.write_req.p_val[3];
uint32_t sliderY = p_attr_req->data.write_req.p_val[5+numButtons];
uint32_t sliderX = p_attr_req->data.write_req.p_val[6+numButtons];
uint32_t buttonMask = 0x00;
for(int i=0;i<numButtons;i++)
{
buttonMask |= (1<<p_attr_req->data.write_req.p_val[5+i]);
}
game_msg_t msg;
msg.evt = MSG_POSITION;
msg.val = 100 - (100*sliderY/255);
wiced_rtos_push_to_queue(&paddleQueue,&msg,0);
if(buttonMask & 0x10)
{
msg.evt = MSG_BUTTON0;
msg.val = 1;
wiced_result_t result=wiced_rtos_push_to_queue(&paddleQueue,&msg,0);
}
status = WICED_BT_GATT_SUCCESS;
}
break;

Program and Test

Mouser PSoC6-WiFi-BT L5 : GoBLE – BLE Remote Control for the Game

Designing low-power, cloud-connected IoT devices with PSoC® 6 MCU’s and WICED® Wi-Fi/Bluetooth

Summary

Although I a like the video game, it is for sure missing something.  That something is IoT.  The first IoT thing that we will do to the game is to add a BLE remote control.  I wanted a pre-done remote control that could be downloaded from the App store.  After looking around a little bit I found GoBle.  I published a detailed article about GoBle here, but I’ll explain enough to make it work with the game.

Here is a screen shot of what the remote control looks like.  You can see that on the left there is a joystick, and on the right there are some buttons.  My son tells me that this is a classic layout for a remote control.

This remote control works as a “Central” meaning it knows how to connect to Peripherals.  For this lesson we will turn on the CYW4343W and make it be a Bluetooth Peripheral.

To implement this lesson I will follow these steps:

  1. Create a folder called “L5GoBle”
  2. Create a makefile called L5GoBle.mk
  3. Setup a GATT database by creating GoBle_db.h and GoBle_db.c
  4. Setup wiced_bt_cfg.c
  5. Create GoBleThread.c
  6. Create GoBle.c to startup the GoBleThread
  7. Build, Program and Test

Create a directory called “L5GoBle”

Create a makefile called L5GoBle.mk

NAME := App_WStudio_L5GoBle
$(NAME)_SOURCES    := GoBle.c \
GoBleThread.c \
GoBle_db.c \
wiced_bt_cfg.c
$(NAME)_INCLUDES   := .
$(NAME)_COMPONENTS += libraries/drivers/bluetooth/low_energy 

Setup a GATT database by creating GoBle_db.h and GoBle_db.c

Create a file called “GoBle_db.h”

// GoBle_db.h
#ifndef __GATT_DATABASE_H__
#define __GATT_DATABASE_H__
#include "wiced.h"
#define __UUID_GOBLE                                 0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xb0, 0xdf, 0x00, 0x00
#define __UUID_GOBLE_SERIALPORTID                    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xb1, 0xdf, 0x00, 0x00
// ***** Primary Service 'Generic Attribute'
#define HDLS_GENERIC_ATTRIBUTE                       0x0001
// ***** Primary Service 'Generic Access'
#define HDLS_GENERIC_ACCESS                          0x0014
// ----- Characteristic 'Device Name'
#define HDLC_GENERIC_ACCESS_DEVICE_NAME              0x0015
#define HDLC_GENERIC_ACCESS_DEVICE_NAME_VALUE        0x0016
// ----- Characteristic 'Appearance'
#define HDLC_GENERIC_ACCESS_APPEARANCE               0x0017
#define HDLC_GENERIC_ACCESS_APPEARANCE_VALUE         0x0018
// ***** Primary Service 'GoBle'
#define HDLS_GOBLE                                   0x0028
// ----- Characteristic 'SerialPortId'
#define HDLC_GOBLE_SERIALPORTID                      0x0029
#define HDLC_GOBLE_SERIALPORTID_VALUE                0x002A
// ===== Descriptor 'Client Configuration'
#define HDLD_GOBLE_SERIALPORTID_CLIENT_CONFIGURATION 0x002B
// External definitions
extern const uint8_t  gatt_database[];
extern const uint16_t gatt_database_len;
extern uint8_t BT_LOCAL_NAME[];
extern const uint16_t BT_LOCAL_NAME_CAPACITY;
#endif /* __GATT_DATABASE_H__ */

Create a file called “GoBle.c”

/*
* This file has been automatically generated by the WICED 20719-B1 Designer.
* BLE device's GATT database and device configuration.
*
*/
// GoBle_db.c
#include "GoBle_db.h"
#include "wiced.h"
#include "wiced_bt_uuid.h"
#include "wiced_bt_gatt.h"
/*************************************************************************************
** GATT server definitions
*************************************************************************************/
const uint8_t gatt_database[] = // Define GATT database
{
/* Primary Service 'Generic Attribute' */
PRIMARY_SERVICE_UUID16 (HDLS_GENERIC_ATTRIBUTE, UUID_SERVICE_GATT),
/* Primary Service 'Generic Access' */
PRIMARY_SERVICE_UUID16 (HDLS_GENERIC_ACCESS, UUID_SERVICE_GAP),
/* Primary Service 'GoBle' */
PRIMARY_SERVICE_UUID128 (HDLS_GOBLE, __UUID_GOBLE),
/* Characteristic 'SerialPortId' */
CHARACTERISTIC_UUID128_WRITABLE (HDLC_GOBLE_SERIALPORTID, HDLC_GOBLE_SERIALPORTID_VALUE,
__UUID_GOBLE_SERIALPORTID, LEGATTDB_CHAR_PROP_READ | LEGATTDB_CHAR_PROP_WRITE_NO_RESPONSE | LEGATTDB_CHAR_PROP_WRITE | LEGATTDB_CHAR_PROP_NOTIFY,
LEGATTDB_PERM_READABLE | LEGATTDB_PERM_WRITE_CMD | LEGATTDB_PERM_WRITE_REQ),
/* Descriptor 'Client Characteristic Configuration' */
CHAR_DESCRIPTOR_UUID16_WRITABLE (HDLD_GOBLE_SERIALPORTID_CLIENT_CONFIGURATION,
UUID_DESCRIPTOR_CLIENT_CHARACTERISTIC_CONFIGURATION, LEGATTDB_PERM_READABLE | LEGATTDB_PERM_WRITE_REQ | LEGATTDB_PERM_AUTH_WRITABLE),
};
// Length of the GATT database
const uint16_t gatt_database_len = sizeof(gatt_database);

Setup wiced_bt_cfg.c

The WICED Bluetooth Configuration file is called “wiced_bt_config.c”.  The only change I made from the default is the timeout value of the advertising.  You can copy this directly into your file.

/*
* This file has been automatically generated by the WICED 20719-B1 Designer.
* Device Configuration.
*
*/
/** wiced_bt_cfg.c
*
* Runtime Bluetooth stack configuration parameters
*
*/
#include "wiced_bt_dev.h"
#include "wiced_bt_ble.h"
#include "wiced_bt_uuid.h"
#include "wiced_bt_gatt.h"
#include "wiced_bt_avrc.h"
#include "wiced_bt_cfg.h"
/* Null-Terminated Local Device Name */
uint8_t BT_LOCAL_NAME[] = { 'G','o','B','l','e','T','e','s','t','\0' };
const uint16_t BT_LOCAL_NAME_CAPACITY = sizeof(BT_LOCAL_NAME);
/*******************************************************************
* wiced_bt core stack configuration
******************************************************************/
const wiced_bt_cfg_settings_t wiced_bt_cfg_settings =
{
.device_name =                          (uint8_t*)BT_LOCAL_NAME,                                    /**< Local device name (NULL terminated) */
.device_class =                         {0x00, 0x00, 0x00},                                         /**< Local device class */
.security_requirement_mask =            BTM_SEC_NONE,                                               /**< Security requirements mask (BTM_SEC_NONE, or combination of BTM_SEC_IN_AUTHENTICATE, BTM_SEC_OUT_AUTHENTICATE, BTM_SEC_ENCRYPT */
.max_simultaneous_links =               1,                                                          /**< Maximum number of simultaneous links to different devices */
/* BR/EDR Scan Configuration */
.br_edr_scan_cfg = {
.inquiry_scan_type =                BTM_SCAN_TYPE_STANDARD,                                     /**< Inquiry Scan Type (BTM_SCAN_TYPE_STANDARD or BTM_SCAN_TYPE_INTERLACED) */
.inquiry_scan_interval =            0x0000,                                                     /**< Inquiry Scan Interval (0 to use default) */
.inquiry_scan_window =              0x0000,                                                     /**< Inquiry Scan Window (0 to use default) */
.page_scan_type =                   BTM_SCAN_TYPE_STANDARD,                                     /**< Page Scan Type (BTM_SCAN_TYPE_STANDARD or BTM_SCAN_TYPE_INTERLACED) */
.page_scan_interval =               0x0000,                                                     /**< Page Scan Interval (0 to use default) */
.page_scan_window =                 0x0000,                                                     /**< Page Scan Window (0 to use default) */
},
/* BLE Scan Settings */
.ble_scan_cfg = {
.scan_mode =                        BTM_BLE_SCAN_MODE_PASSIVE,                                  /**< BLE Scan Mode (BTM_BLE_SCAN_MODE_PASSIVE or BTM_BLE_SCAN_MODE_ACTIVE) */
/* Advertisement Scan Configuration */
.high_duty_scan_interval =          WICED_BT_CFG_DEFAULT_HIGH_DUTY_SCAN_INTERVAL,               /**< High Duty Scan Interval */
.high_duty_scan_window =            WICED_BT_CFG_DEFAULT_HIGH_DUTY_SCAN_WINDOW,                 /**< High Duty Scan Window */
.high_duty_scan_duration =          5,                                                          /**< High Duty Scan Duration in seconds (0 for infinite) */
.low_duty_scan_interval =           WICED_BT_CFG_DEFAULT_LOW_DUTY_SCAN_INTERVAL,                /**< Low Duty Scan Interval */
.low_duty_scan_window =             WICED_BT_CFG_DEFAULT_LOW_DUTY_SCAN_WINDOW,                  /**< Low Duty Scan Window */
.low_duty_scan_duration =           5,                                                          /**< Low Duty Scan Duration in seconds (0 for infinite) */
/* Connection Scan Configuration */
.high_duty_conn_scan_interval =     WICED_BT_CFG_DEFAULT_HIGH_DUTY_CONN_SCAN_INTERVAL,          /**< High Duty Connection Cycle Connection Scan Interval */
.high_duty_conn_scan_window =       WICED_BT_CFG_DEFAULT_HIGH_DUTY_CONN_SCAN_WINDOW,            /**< High Duty Connection Cycle Connection Scan Window */
.high_duty_conn_duration =          30,                                                         /**< High Duty Connection Cycle Connection Duration in seconds (0 for infinite) */
.low_duty_conn_scan_interval =      WICED_BT_CFG_DEFAULT_LOW_DUTY_CONN_SCAN_INTERVAL,           /**< Low Duty Connection Cycle Connection Scan Interval */
.low_duty_conn_scan_window =        WICED_BT_CFG_DEFAULT_LOW_DUTY_CONN_SCAN_WINDOW,             /**< Low Duty Connection Cycle Connection Scan Window */
.low_duty_conn_duration =           30,                                                         /**< Low Duty Connection Cycle Connection Duration in seconds (0 for infinite) */
/* Connection Configuration */
.conn_min_interval =                WICED_BT_CFG_DEFAULT_CONN_MIN_INTERVAL,                     /**< Minimum Connection Interval */
.conn_max_interval =                WICED_BT_CFG_DEFAULT_CONN_MAX_INTERVAL,                     /**< Maximum Connection Interval */
.conn_latency =                     WICED_BT_CFG_DEFAULT_CONN_LATENCY,                          /**< Connection Latency */
.conn_supervision_timeout =         WICED_BT_CFG_DEFAULT_CONN_SUPERVISION_TIMEOUT,              /**< Connection Link Supervision Timeout */
},
/* BLE Advertisement Settings */
.ble_advert_cfg = {
.channel_map =                      BTM_BLE_ADVERT_CHNL_37 |                                    /**< Advertising Channel Map (mask of BTM_BLE_ADVERT_CHNL_37, BTM_BLE_ADVERT_CHNL_38, BTM_BLE_ADVERT_CHNL_39) */
BTM_BLE_ADVERT_CHNL_38 |
BTM_BLE_ADVERT_CHNL_39,
.high_duty_min_interval =           WICED_BT_CFG_DEFAULT_HIGH_DUTY_ADV_MIN_INTERVAL,            /**< High Duty Undirected Connectable Minimum Advertising Interval */
.high_duty_max_interval =           WICED_BT_CFG_DEFAULT_HIGH_DUTY_ADV_MAX_INTERVAL,            /**< High Duty Undirected Connectable Maximum Advertising Interval */
.high_duty_duration =               0,                                                         /**< High Duty Undirected Connectable Advertising Duration in seconds (0 for infinite) */
.low_duty_min_interval =            WICED_BT_CFG_DEFAULT_LOW_DUTY_ADV_MIN_INTERVAL,             /**< Low Duty Undirected Connectable Minimum Advertising Interval */
.low_duty_max_interval =            WICED_BT_CFG_DEFAULT_LOW_DUTY_ADV_MAX_INTERVAL,             /**< Low Duty Undirected Connectable Maximum Advertising Interval */
.low_duty_duration =                60,                                                         /**< Low Duty Undirected Connectable Advertising Duration in seconds (0 for infinite) */
.high_duty_directed_min_interval =  WICED_BT_CFG_DEFAULT_HIGH_DUTY_DIRECTED_ADV_MIN_INTERVAL,   /**< High Duty Directed Minimum Advertising Interval */
.high_duty_directed_max_interval =  WICED_BT_CFG_DEFAULT_HIGH_DUTY_DIRECTED_ADV_MAX_INTERVAL,   /**< High Duty Directed Maximum Advertising Interval */
.low_duty_directed_min_interval =   WICED_BT_CFG_DEFAULT_LOW_DUTY_DIRECTED_ADV_MIN_INTERVAL,    /**< Low Duty Directed Minimum Advertising Interval */
.low_duty_directed_max_interval =   WICED_BT_CFG_DEFAULT_LOW_DUTY_DIRECTED_ADV_MAX_INTERVAL,    /**< Low Duty Directed Maximum Advertising Interval */
.low_duty_directed_duration =       30,                                                         /**< Low Duty Directed Advertising Duration in seconds (0 for infinite) */
.high_duty_nonconn_min_interval =   WICED_BT_CFG_DEFAULT_HIGH_DUTY_NONCONN_ADV_MIN_INTERVAL,    /**< High Duty Non-Connectable Minimum Advertising Interval */
.high_duty_nonconn_max_interval =   WICED_BT_CFG_DEFAULT_HIGH_DUTY_NONCONN_ADV_MAX_INTERVAL,    /**< High Duty Non-Connectable Maximum Advertising Interval */
.high_duty_nonconn_duration =       30,                                                         /**< High Duty Non-Connectable Advertising Duration in seconds (0 for infinite) */
.low_duty_nonconn_min_interval =    WICED_BT_CFG_DEFAULT_LOW_DUTY_NONCONN_ADV_MIN_INTERVAL,     /**< Low Duty Non-Connectable Minimum Advertising Interval */
.low_duty_nonconn_max_interval =    WICED_BT_CFG_DEFAULT_LOW_DUTY_NONCONN_ADV_MAX_INTERVAL,     /**< Low Duty Non-Connectable Maximum Advertising Interval */
.low_duty_nonconn_duration =        0,                                                          /**< Low Duty Non-Connectable Advertising Duration in seconds (0 for infinite) */
},
/* GATT Configuration */
.gatt_cfg = {
.appearance =                       0x0000,                                                     /**< GATT Appearance */
.client_max_links =                 1,                                                          /**< Client Config: Maximum number of servers that local client can connect to */
.server_max_links =                 1,                                                          /**< Server Config: Maximum number of remote client connections allowed by local server */
.max_attr_len =                     512,                                                        /**< Maximum attribute length; wiced_bt_cfg must have a corresponding buffer pool that can hold this length */
.max_mtu_size =                     515,                                                        /**< Maximum MTU size for GATT connections, should be between 23 and (max_attr_len + 5) */
},
/* RFCOMM Configuration */
.rfcomm_cfg = {
.max_links =                        0,                                                          /**< Maximum number of simultaneous connected remote devices */
.max_ports =                        0,                                                          /**< Maximum Number of simultaneous RFCOMM ports */
},
/* Application-Managed L2CAP Protocol Configuration */
.l2cap_application = {
.max_links =                        0,                                                          /**< Maximum Number of Application-Managed L2CAP Links (BR/EDR and BLE) */
.max_psm =                          0,                                                          /**< Maximum Number of Application-Managed BR/EDR PSMs */
.max_channels =                     0,                                                          /**< Maximum Number of Application-Managed BR/EDR Channels */
.max_le_psm =                       0,                                                          /**< Maximum Number of Application-Managed LE PSMs */
.max_le_channels =                  0,                                                          /**< Maximum Number of Application-Managed LE Channels */
.max_le_l2cap_fixed_channels =      0,                                                          /**< Maximum Number of Application-Managed LE L2CAP Fixed Channnels supported (in addition to mandatory channels 4, 5, and 6 */
},
/* Audio/Video Distribution Configuration */
.avdt_cfg = {
.max_links =                        0,                                                          /**< Maximum Number of simultaneous Audio/Video links */
.max_seps =                         0,                                                          /**< Maximum Number of stream end points */
},
/* AVRC Configuration */
.avrc_cfg = {
.roles =                            0,                                                          /**< Local Roles supported (AVRC_CONN_INITIATOR or AVRC_CONN_ACCEPTOR) */
.max_links =                        0,                                                          /**< Maximum simultaneous Remote Control links */
},
/* LE Address Resolution Database Settings */
.addr_resolution_db_size =              10,                                                         /**< LE Address Resolution Database Size - Effective only for pre-4.2 controller */
.max_number_of_buffer_pools =           4,                                                          /**< Maximum number of buffer pools in p_btm_cfg_buf_pools and by wiced_create_pool */
.rpa_refresh_timeout =                  0,         /**< Interval of random address refreshing - secs */
};
/*******************************************************************
* wiced_bt_stack buffer pool configuration
*
* Configure buffer pools used by the stack
*
* Pools must be ordered in increasing buf_size.
* If a pools runs out of buffers, the next pool will be used.
******************************************************************/
const wiced_bt_cfg_buf_pool_t wiced_bt_cfg_buf_pools[WICED_BT_CFG_NUM_BUF_POOLS] =
{
/*  { buf_size, buf_count, }, */
{ 64,       12,        }, /* Small Buffer Pool */
{ 360,      4,         }, /* Medium Buffer Pool (used for HCI & RFCOMM control messages, min recommended size is 360) */
{ 512,      4,         }, /* Large Buffer Pool  (used for HCI ACL messages) */
{ 1024,     2,         }, /* Extra Large Buffer Pool (used for AVDT media packets and miscellaneous; if not needed, set buf_count to 0) */
};

Create GoBleThread.c

In  order for the GoBleThread to work you need:

  1. The includes for the GATT Database and the WICED bluetooth stack.
  2. External References to the GATT Database.
  3. A few function prototypes.
  4. A function called “GoBleThread_start” to startup the Bluetooth stack and get things going. This includes providing Bluetooth management and GATT event handler functions.
#include "GoBle_db.h"
#include "wiced.h"
#include "wiced_bt_ble.h"
#include "wiced_bt_gatt.h"
#include "wiced_bt_stack.h"
/*******************************************************************
* Variable Definitions
******************************************************************/
extern const wiced_bt_cfg_settings_t wiced_bt_cfg_settings;
extern const wiced_bt_cfg_buf_pool_t wiced_bt_cfg_buf_pools[WICED_BT_CFG_NUM_BUF_POOLS];
/*******************************************************************
* Function Prototypes
******************************************************************/
static wiced_bt_dev_status_t  goble_management_callback    ( wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data );
static void                   goble_set_advertisement_data ( void );
static wiced_bt_gatt_status_t goble_event_handler          ( wiced_bt_gatt_evt_t  event, wiced_bt_gatt_event_data_t *p_event_data );
/*******************************************************************
* Function Definitions
******************************************************************/
void GoBleThread_start(void)
{
wiced_bt_stack_init(goble_management_callback, &wiced_bt_cfg_settings, wiced_bt_cfg_buf_pools);
}

Create a function to setup the advertising data.  The GoBle iOS App looks for Peripherals that are advertising the UUID of the GoBLE Service.

/* Set Advertisement Data */
void goble_set_advertisement_data( void )
{
wiced_bt_ble_advert_elem_t adv_elem[3] = { 0 };
uint8_t adv_flag = BTM_BLE_GENERAL_DISCOVERABLE_FLAG | BTM_BLE_BREDR_NOT_SUPPORTED;
uint8_t num_elem = 0; 
/* Advertisement Element for Flags */
adv_elem[num_elem].advert_type = BTM_BLE_ADVERT_TYPE_FLAG;
adv_elem[num_elem].len = sizeof(uint8_t);
adv_elem[num_elem].p_data = &adv_flag;
num_elem++;
uint8_t gobleuuid[] = {__UUID_GOBLE};
/* Advertisement Element for Name */
adv_elem[num_elem].advert_type = BTM_BLE_ADVERT_TYPE_128SRV_COMPLETE;
adv_elem[num_elem].len = 16;
adv_elem[num_elem].p_data = gobleuuid;
num_elem++;
/* Set Raw Advertisement Data */
wiced_bt_ble_set_raw_advertisement_data(num_elem, adv_elem);
}

The Bluetooth Management Event Handler needs to take actions when the stack turns on, or one of the pairing events occur.

/* Bluetooth Management Event Handler */
wiced_bt_dev_status_t goble_management_callback( wiced_bt_management_evt_t event, wiced_bt_management_evt_data_t *p_event_data )
{
wiced_bt_dev_status_t status = WICED_BT_SUCCESS;
switch (event)
{
case BTM_ENABLED_EVT:
goble_set_advertisement_data();
wiced_bt_gatt_register( goble_event_handler );
wiced_bt_gatt_db_init( gatt_database, gatt_database_len );
wiced_bt_start_advertisements(BTM_BLE_ADVERT_UNDIRECTED_HIGH, 0, NULL);
break;
case BTM_SECURITY_REQUEST_EVT:
wiced_bt_ble_security_grant(p_event_data->security_request.bd_addr, WICED_BT_SUCCESS);
break;
case BTM_PAIRING_IO_CAPABILITIES_BLE_REQUEST_EVT:
p_event_data->pairing_io_capabilities_ble_request.local_io_cap = BTM_IO_CAPABILITIES_NONE;
p_event_data->pairing_io_capabilities_ble_request.oob_data = BTM_OOB_NONE;
p_event_data->pairing_io_capabilities_ble_request.auth_req = BTM_LE_AUTH_REQ_NO_BOND;
break;
case BTM_USER_CONFIRMATION_REQUEST_EVT: // Just confirm
wiced_bt_dev_confirm_req_reply( WICED_BT_SUCCESS , p_event_data->user_confirmation_request.bd_addr);
break;
case BTM_PAIRED_DEVICE_LINK_KEYS_REQUEST_EVT:
WPRINT_APP_INFO(("Paired linke keys\n"));
status = WICED_BT_ERROR;
break;
case BTM_LOCAL_IDENTITY_KEYS_REQUEST_EVT:
case BTM_PAIRING_COMPLETE_EVT:
case BTM_ENCRYPTION_STATUS_EVT:
case BTM_BLE_ADVERT_STATE_CHANGED_EVT:
case BTM_LPM_STATE_LOW_POWER:
break;
default:
WPRINT_APP_INFO(("Unhandled Bluetooth Management Event: 0x%x (%d)\n", event, event));
break;
}
return status;
}

The GATT Event Handler is called

  1. When a connection is made or terminated
  2. When the GoBle app writes to your GATT database.  When that happens we will just printout the value that was written
/* GATT Event Handler */
wiced_bt_gatt_status_t goble_event_handler( wiced_bt_gatt_evt_t event, wiced_bt_gatt_event_data_t *p_event_data )
{
wiced_bt_gatt_status_t status = WICED_BT_GATT_ERROR;
wiced_bt_gatt_attribute_request_t *p_attr_req = NULL;
switch ( event )
{
case GATT_CONNECTION_STATUS_EVT:
if(!p_event_data->connection_status.connected)
{
WPRINT_APP_INFO(("Disconnected\n"));
wiced_bt_start_advertisements(BTM_BLE_ADVERT_UNDIRECTED_HIGH, 0, NULL);
}
else
WPRINT_APP_INFO(("Connected\n"));
break;
case GATT_ATTRIBUTE_REQUEST_EVT:
p_attr_req = &p_event_data->attribute_request;
if( p_attr_req->request_type == GATTS_REQ_TYPE_WRITE  && p_attr_req->data.handle == HDLC_GOBLE_SERIALPORTID_VALUE)
{
uint32_t numButtons = p_attr_req->data.write_req.p_val[3];
uint32_t sliderY = p_attr_req->data.write_req.p_val[5+numButtons];
uint32_t sliderX = p_attr_req->data.write_req.p_val[6+numButtons];
uint32_t buttonMask = 0x00;
for(int i=0;i<numButtons;i++)
{
buttonMask |= (1<<p_attr_req->data.write_req.p_val[5+i]);
}
WPRINT_APP_INFO(("# Buttons = %d ButtonMask=%02X Slider x=%02X Slider Y=%02X Raw=",(int)numButtons,(unsigned int)buttonMask,(unsigned int)sliderX,(unsigned int)sliderY));
for(int i=0;i<p_attr_req->data.write_req.val_len;i++)
{
WPRINT_APP_INFO(("%02X ",p_attr_req->data.write_req.p_val[i]));
}
WPRINT_APP_INFO(("\n"));
status = WICED_BT_GATT_SUCCESS;
}
break;
default:
status = WICED_BT_GATT_SUCCESS;
break;
}
return status;
}

Create GoBleThread.h

#pragma once
extern void GoBleThread_start(void);

Create GoBle.c to startup the GoBleThread

#include "GoBleThread.h"
#include "wiced.h"
/*******************************************************************
* Function Definitions
******************************************************************/
void application_start(void)
{
wiced_init();
GoBleThread_start();
}

Build, Program and Test