CC2340R5: BLE Central enter Exception_handlerSpin() when call GATT_WriteCharValue()

Hello Bryte,

How are you implementing the GATT_Write() function? Could you please share a code snippet of how this function is called and in what context.

I would suggest to use the following example as reference: https://github.com/TexasInstruments-Sandbox/ble_examples/tree/simplelink_low_power_f3_sdk-8.40/examples/rtos/LP_EM_CC2340R5/ble5stack/basic_ble_GATT_client

Best Regards,

David.

Thanks for your reply! I have downloaded the examples on github, I share the code(please do not hesitate to let me show more code, it is not secrety now)  and review example on github again now.

TimerHandle_t hbtTimer = create_periodic_timer(5000, heartbeat_timerCB, (void *)1);

void heartbeat_timerCB(TimerHandle_t xTimer)
{
static uint32 cnt = 0;
Display_doPrintf(displayHandle, my_printLine, 0, "~ ");

if (0 == is_connected) {
cnt=0;
return ;
}

cnt ++;
if (1 == cnt) {
BLEAppUtil_invokeFunction(tx_service_discovery, NULL); // works fine
} else if (2 == cnt) {
BLEAppUtil_invokeFunction(tx_service_discovery_by_uuid, NULL); // works fine
} else if (7 == cnt) {
BLEAppUtil_invokeFunction(tx_ble_ctrl_cmd, NULL); // hang if call GATT_WriteCharValue in it.
}
}


void tx_ble_ctrl_cmd(char* pData)
{
attWriteReq_t writeReq;
uint8_t command;

BLEAppUtil_entityId_t entityid = BLEAppUtil_getSelfEntity();
uint16_t connhd = Connection_getConnhandle(0);

if (wr_handle[0]==0 && wr_handle[1]==0)
return ;

command = (command == CMD_TURN_ON ? CMD_TURN_OFF : CMD_TURN_ON);
writeReq.handle = (wr_handle[1]<<8 | wr_handle[0]);
writeReq.len = sizeof(command);
writeReq.pValue = (uint8 *)&command;
writeReq.sig = 0;
writeReq.cmd = 0;

Display_doPrintf(displayHandle, my_printLine++, 0, "tx_ble_ctrl_cmd_short connhd:%u.entity:%u. hd:0x%x.\n", connhd, entityid, writeReq.handle);
if (65535 == connhd)
return ;
#if 1
bStatus_t ret = GATT_WriteCharValue(connhd, &writeReq, entityid); // hang, 
Display_doPrintf(displayHandle, my_printLine++, 0, "GATT_WriteCharValue : %u.\n", ret);
#else
bStatus_t ret = GATT_WriteLongCharValue(connhd, &writeReq, entityid); 
Display_doPrintf(displayHandle, my_printLine++, 0, "GATT_WriteLongCharValue : %u.\n", ret);
#endif
}

Calling GATT_WriteLongCharValue() will not hang, but get 

reqopc:22, errcode:9
#define ATT_ERR_PREPARE_QUEUE_FULL 0x09 //!< Too many prepare writes have been queued

Hello,

Thanks. What is the size of the data you are sending (command)? Also how are you creating the periodic timer?

BR,

David.

1. The size of data is 1 Byte (uint8_t command;).

2. 

TimerHandle_t create_periodic_timer(uint32_t period_ms, TimerCallbackFunction_t callback, void *timer_id)
{
TimerHandle_t xTimer;
BaseType_t xResult;

xTimer = xTimerCreate(
"UserTimer",
pdMS_TO_TICKS(period_ms),
pdTRUE,
timer_id,
callback
);

if (xTimer != NULL)
{
xResult = xTimerStart(xTimer, 0);
if (xResult != pdPASS)
{
xTimerDelete(xTimer, 0);
xTimer = NULL;
}
}

return xTimer;
}

3. I have compared https://github.com/TexasInstruments-Sandbox/ble_examples/tree/simplelink_low_power_f3_sdk-8.40/examples/rtos/LP_EM_CC2340R5/ble5stack/basic_ble_GATT_client/app and simplelink_lowpower_f3_sdk_8_40_00_61\examples\rtos\LP_EM_CC2340R5\ble5stack\basic_ble\app, There are only diff in centralConnParams and centralScanInitParams, I try the diff accoding 8_40's, it also hangs on GATT_WriteCharValue.

Ignore the part 3. I shoud comapre simplelink_lowpower_f3_sdk_9_11_00_18\examples\rtos\LP_EM_CC2340R5\ble\basic_ble\app, not simplelink_lowpower_f3_sdk_8_40_00_61

I have compared https://github.com/TexasInstruments-Sandbox/ble_examples/tree/simplelink_low_power_f3_sdk-8.40/examples/rtos/LP_EM_CC2340R5/ble5stack/basic_ble_GATT_client/app with simplelink_lowpower_f3_sdk_9_11_00_18\examples\rtos\LP_EM_CC2340R5\ble\basic_ble\app. 

There are also only diff in centralConnParams and centralScanInitParams, ignore other diff would not have relation with the issue obviously.

I tried to merge the diff and test, the same issue.

GATT_ReadCharValue() works fine in the same flow.

It will not hang when call GATT_WriteCharValue() in app_connection.c GATT_EventHandler(), but the peripheral receives malformed packet, Attribute Write does not work, while service discovery from central and notify from peripheral work fine.

Hello Bryte,

I will try to reproduce the GATT_WriteCharValue now with the latest SDK and report back. Please let me know if you have any updates now.

BR,

David.