Hello,
I'm using BMA253 sensor on custom board with nRF52832.
I've implemented bus write and read functions using nrf_twi_mngr.
Here is code:
/* \Brief: The function is used as I2C bus write
* \Return : Status of the I2C write
* \param dev_addr : The device address of the sensor
* \param reg_addr : Address of the first register, where data is to be written
* \param reg_data : It is a value held in the array,
* which is written in the register
* \param cnt : The no of bytes of data to be written
*/
static s8 BMA253_TWI_bus_write(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
s32 iError = BMA2x2_INIT_VALUE;
u8 array[TWI_BUFFER_LEN] = {BMA2x2_INIT_VALUE};
u8 stringpos = BMA2x2_INIT_VALUE;
array[BMA2x2_INIT_VALUE] = reg_addr;
for (stringpos = BMA2x2_INIT_VALUE; stringpos < cnt; stringpos++) {
array[stringpos + BMA2x2_BUS_READ_WRITE_ARRAY_INDEX] =
*(reg_data + stringpos);
}
nrf_twi_mngr_transfer_t const transfers[] =
{
NRF_TWI_MNGR_WRITE(dev_addr, array, cnt + 1, 0)
};
iError = nrf_twi_mngr_perform(&m_nrf_twi_mngr, NULL, transfers, sizeof(transfers) / sizeof(transfers[0]), NULL);
APP_ERROR_CHECK(iError);
return (s8)iError;
}
/* \Brief: The function is used as I2C bus read
* \Return : Status of the I2C read
* \param dev_addr : The device address of the sensor
* \param reg_addr : Address of the first register, where data is going to be read
* \param reg_data : This is the data read from the sensor, which is held in an array
* \param cnt : The no of data to be read
*/
static s8 BMA253_TWI_bus_read(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
s32 iError = BMA2x2_INIT_VALUE;
u8 array[TWI_BUFFER_LEN] = {BMA2x2_INIT_VALUE};
u8 stringpos = BMA2x2_INIT_VALUE;
array[BMA2x2_INIT_VALUE] = reg_addr;
nrf_twi_mngr_transfer_t const transfers[] =
{
NRF_TWI_MNGR_WRITE(dev_addr, ®_addr, 1, NRF_TWI_MNGR_NO_STOP),
NRF_TWI_MNGR_READ (dev_addr, array, cnt, 0)
};
iError = nrf_twi_mngr_perform(&m_nrf_twi_mngr, NULL, transfers, sizeof(transfers) / sizeof(transfers[0]), NULL);
APP_ERROR_CHECK(iError);
for (stringpos = BMA2x2_INIT_VALUE; stringpos < cnt; stringpos++)
*(reg_data + stringpos) = array[stringpos];
return (s8)iError;
}It is working, but I would like to change `nrf_twi_mngr_perform` function to `nrf_twi_mngr_schedule`.
For this purpose I've added `transaction` structures to my code, and made both `transfers` and `transaction` static.
Here how it looks now:
static void BMA253_TWI_bus_write_cb(ret_code_t result, void * p_user_data)
{
}
static void BMA253_TWI_bus_read_cb(ret_code_t result, void * p_user_data)
{
}
/* \Brief: The function is used as I2C bus write
* \Return : Status of the I2C write
* \param dev_addr : The device address of the sensor
* \param reg_addr : Address of the first register, where data is to be written
* \param reg_data : It is a value held in the array,
* which is written in the register
* \param cnt : The no of bytes of data to be written
*/
static s8 BMA253_TWI_bus_write(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
s32 iError = BMA2x2_INIT_VALUE;
static u8 array[TWI_BUFFER_LEN] = {BMA2x2_INIT_VALUE};
u8 stringpos = BMA2x2_INIT_VALUE;
array[BMA2x2_INIT_VALUE] = reg_addr;
for (stringpos = BMA2x2_INIT_VALUE; stringpos < cnt; stringpos++) {
array[stringpos + BMA2x2_BUS_READ_WRITE_ARRAY_INDEX] =
*(reg_data + stringpos);
}
static nrf_twi_mngr_transfer_t const transfers[] =
{
NRF_TWI_MNGR_WRITE(dev_addr, array, cnt + 1, 0)
};
static nrf_twi_mngr_transaction_t NRF_TWI_MNGR_BUFFER_LOC_IND transaction =
{
.callback = BMA253_TWI_bus_write_cb,
.p_user_data = NULL,
.p_transfers = transfers,
.number_of_transfers = sizeof(transfers) / sizeof(transfers[0])
};
iError = nrf_twi_mngr_schedule(&m_nrf_twi_mngr, &transaction);
APP_ERROR_CHECK(iError);
return (s8)iError;
}
/* \Brief: The function is used as I2C bus read
* \Return : Status of the I2C read
* \param dev_addr : The device address of the sensor
* \param reg_addr : Address of the first register, where data is going to be read
* \param reg_data : This is the data read from the sensor, which is held in an array
* \param cnt : The no of data to be read
*/
static s8 BMA253_TWI_bus_read(u8 dev_addr, u8 reg_addr, u8 *reg_data, u8 cnt)
{
s32 iError = BMA2x2_INIT_VALUE;
static u8 array[TWI_BUFFER_LEN] = {BMA2x2_INIT_VALUE};
u8 stringpos = BMA2x2_INIT_VALUE;
array[BMA2x2_INIT_VALUE] = reg_addr;
static nrf_twi_mngr_transfer_t const transfers[] =
{
NRF_TWI_MNGR_WRITE(dev_addr, ®_addr, 1, NRF_TWI_MNGR_NO_STOP),
NRF_TWI_MNGR_READ (dev_addr, array, cnt, 0)
};
static nrf_twi_mngr_transaction_t NRF_TWI_MNGR_BUFFER_LOC_IND transaction =
{
.callback = BMA253_TWI_bus_read_cb,
.p_user_data = NULL,
.p_transfers = transfers,
.number_of_transfers = sizeof(transfers) / sizeof(transfers[0])
};
iError = nrf_twi_mngr_schedule(&m_nrf_twi_mngr, &transaction);
APP_ERROR_CHECK(iError);
for (stringpos = BMA2x2_INIT_VALUE; stringpos < cnt; stringpos++)
*(reg_data + stringpos) = array[stringpos];
return (s8)iError;
}
However I've got this errors:
error: initializer element is not constant NRF_TWI_MNGR_WRITE(dev_addr, array, cnt + 1, 0) error: initializer element is not constant NRF_TWI_MNGR_WRITE(dev_addr, ®_addr, 1, NRF_TWI_MNGR_NO_STOP), error: initializer element is not constant NRF_TWI_MNGR_READ (dev_addr, array, cnt, 0) etc.
What else should I do to proper replace nrf_twi_mngr_perform to nrf_twi_mngr_schedule?
