RTOS/LAUNCHXL-CC2640R2: I2C_transfer function is not working in timer callback function

Can you provide some more information about how the I2C handle and global parameters are passed?

Thanks,
Chris

Hi,

Please consider blestack/OAD_Off_Chip example. I added the code below to the end of the "SimplePeripheral_init" function in the "simple_pheripheral_oad_offchip.c";

  /* Call driver init functions */
  Board_initGeneral();

  GPIO_init(); //used for whole gpio input and output
  I2C_init();
  SPI_init();

  /* Create I2C for usage */
  I2C_Params_init(&glb_i2cParams);
  glb_i2cParams.bitRate = I2C_400kHz;
  glb_i2c = I2C_open(Board_I2C_TMP, &glb_i2cParams);
  if (glb_i2c == NULL)
  {
      while(1){}
  }


  uint8_t rxBuffer[1];
  uint8_t LSM9DS1_AG_ADDR = GetAccelGyroAddressOfSelectedSensor(MASTER_DoF);
  uint8_t LSM9DS1_M_ADDR  = GetMagnetoAddressOfSelectedSensor(MASTER_DoF);


  if (ND_ReadBytes(&glb_i2c, LSM9DS1_AG_ADDR, WHO_AM_I_XG, rxBuffer, 1) == false)
  {
      while(1){}
  }
  else
  {
      if(rxBuffer[0] != (uint8_t)WHO_AM_I_AG_RSP)
      {
          while(1){}
      }
  }

Also here are my global variables that are defined in "simple_pheripheral_oad_offchip.c";

static int16_t gx = 0, gy = 0, gz = 0;
static bool timerStarted = false;

static I2C_Handle      glb_i2c;
static I2C_Params      glb_i2cParams;

Also I added the code below in the "SimplePeripheral_taskFxn" and just under the "SimplePeripheral_init();" line in "simple_pheripheral_oad_offchip.c";

  //clock init, reference link is: coecsl.ece.illinois.edu/.../SYSBIOS_usersguide.pdf
  Clock_Params clockParams;
  Clock_Handle myClock;
  Error_Block eb;
  Error_init(&eb);
  Clock_Params_init(&clockParams);
  clockParams.period = DD_SYSTEM_GENERAL_TIMER_PERIOD;
  clockParams.startFlag = TRUE;
  clockParams.arg = (UArg)DD_TIMER_ARG;
  myClock = Clock_create(DD_SystemGeneralTimerHandle, DD_CLOCK_TIMEOUT, &clockParams, &eb);
  if (myClock == NULL)
  {
      while(1){}
  }

And here is my timer callback function below;

static void DD_SystemGeneralTimerHandle(UArg arg)
{
    GPIO_toggle(Board_GPIO_LED0);
    if(timerStarted == false)
        return;
    timerStarted = false;

    uint8_t LSM9DS1_AG_ADDR = GetAccelGyroAddressOfSelectedSensor(MASTER_DoF);
    uint8_t LSM9DS1_M_ADDR  = GetMagnetoAddressOfSelectedSensor(MASTER_DoF);

    uint8_t temp[6] = {0, 0, 0, 0, 0, 0}; // We'll read six bytes from the gyro into temp
    if(ND_ReadBytes(&glb_i2c, LSM9DS1_AG_ADDR, OUT_X_L_G, temp, 6) == false) // Read 6 bytes, beginning at OUT_X_L_G
    {
        while(1){}
    }
    else
    {
        (gx) = (int16_t)((temp[1] << 8) | temp[0]); // Store x-axis values into gx
        (gy) = (int16_t)((temp[3] << 8) | temp[2]); // Store y-axis values into gy
        (gz) = (int16_t)((temp[5] << 8) | temp[4]); // Store z-axis values into gz
    }
}

As you can see, int the timer callback, I2C communication started if "timerStarted" variable is true. I will make "timerStarted" variable true later. I will explain it.

Also there is "ND_ReadBytes" function above and it is like that;

bool ND_ReadBytes(I2C_Handle *i2c, uint8_t devaddress, uint8_t regaddress, uint8_t *buffer, uint8_t len)
{
    uint8_t txBuffer[1];
    I2C_Transaction i2cTransaction;

    txBuffer[0] = regaddress;
    i2cTransaction.slaveAddress = devaddress;
    i2cTransaction.writeBuf = txBuffer;
    i2cTransaction.writeCount = 1;
    i2cTransaction.readBuf = buffer;
    i2cTransaction.readCount = len;

    return I2C_transfer((*i2c), &i2cTransaction);
}

And lastly, I just want to read sensor variables with user's wish. It means that, if a user send (let's say) 0xAA value via characteristic 1, then I make "timerStarted " variable true. By this way, successive sensor reading process can be started. By the way, I am sure that sensor reading time is not exceeding timer period. I just make "timerStarted" variable true just under the "SimplePeripheral_processCharValueChangeEvt" function's case "CUSTOM_PROFILE_CHAR1"

With this method, "ND_ReadBytes" function returns false in the timer callback.

If I do not make "timerStarted " variable true in the code place that I explained above and I just write here the following code (just like in the timer callback);

    uint8_t LSM9DS1_AG_ADDR = GetAccelGyroAddressOfSelectedSensor(MASTER_DoF);
    uint8_t LSM9DS1_M_ADDR  = GetMagnetoAddressOfSelectedSensor(MASTER_DoF);

    uint8_t temp[6] = {0, 0, 0, 0, 0, 0}; // We'll read six bytes from the gyro into temp
    if(ND_ReadBytes(&glb_i2c, LSM9DS1_AG_ADDR, OUT_X_L_G, temp, 6) == false) // Read 6 bytes, beginning at OUT_X_L_G
    {
        while(1){}
    }
    else
    {
        (gx) = (int16_t)((temp[1] << 8) | temp[0]); // Store x-axis values into gx
        (gy) = (int16_t)((temp[3] << 8) | temp[2]); // Store y-axis values into gy
        (gz) = (int16_t)((temp[5] << 8) | temp[4]); // Store z-axis values into gz
    }

then the "ND_ReadBytes" function returns true.

Thanks,

Dogus

Sorry for the delay. A couple of us thought the other person was handling this thread. Someone will reach out soon.

Hi,

I will convert my structure as you describe. 

Thanks for your reply.

Dogus