continuous data about example twi_master_using_app_twi

[Yoojin.Jang]

hello. I want use I2C program. so, I used twi_master_using_app_twi example. SDA is output only 1byte(0x21). I need to output a continuous 5byte. Where do I need to modify the part. thank you.

[Artucas]

You have a function to send data. Second parameter in this function is 0x40 (it is address of my sensor). Third parameter is a pointer to data array which you want to send, fourth parameter is the length in bytes how much bytes you want to send.

ret_code = nrf_drv_twi_tx(&p_twi_instance, 0x40, &dr, 1, false);
APP_ERROR_CHECK(ret_code); // Check for errors in return value

So to send 5 data bytes to the sensor, you cand have something like this

#define DATA_ARRAY_LEN 5
uint8_t data[DATA_ARRAY_LEN] = {0x22, 0x33, 0xFF, 0x10, 0x3A};
uint8_t dev_address = 0x40;

Then in the main program

int main(void)
{
  // ..... 
      ret_code = nrf_drv_twi_tx(&p_twi_instance, dev_address, data, DATA_ARRAY_LEN, false);
      APP_ERROR_CHECK(ret_code); // Check for errors in return value
}

Not sure this will compile because it is blind written, but you should get the idea.

[Artucas]

If it solved your problem, please mark question as answered, so other could find this easier. You can do it by pressing grey circle near to my answer.