52810, LIS3DH, i2c using TWI, got NRF_ERROR_DRV_TWI_ERR_ANACK while calling nrf_drv_twi_tx

Question

52810, LIS3DH, I call nrf_drv_twi_tx got NRF_ERROR_DRV_TWI_ERR_ANACK return using either TWI/ or TWIM . Here is my code: 
 const nrf_drv_twi_config_t config = { .scl = TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER, .sda = TWI_MASTER_CONFIG_DATA_PIN_NUMBER, .frequency = NRF_DRV_TWI_FREQ_100K, .interrupt_priority = APP_IRQ_PRIORITY_HIGH, .clear_bus_init = true }; 
 err_code = nrf_drv_twi_init(&m_twi, &config, NULL, NULL); APP_ERROR_CHECK(err_code); nrf_drv_twi_enable(&m_twi); 
 uint8_t buf[7]; 
 buf[0] = WHO_AM_I; 
 nrf_drv_twi_tx(&m_twi, LIS3DH_ACC_I2C_SAD_H, buf[0], 1, false); 
 
 Please help me out, thanks a lot.

Karl Ylvisaker · Accepted Answer

Hello, Here is an exempt from the Infocenter documentation for the TWI driver, regarding this particular error: 
 NRFX_ERROR_DRV_TWI_ERR_ANACK - Negative acknowledgement (NACK) is received after sending the address in polling mode. 
 So, it seems your TWI slave is sending a NACK. You should check what your slave datasheet says about this. Based on the code you have provided, there is not much more I can say about this. 
 uint8_t buf[7]; 
 buf[0] = WHO_AM_I; 
 nrf_drv_twi_tx(&m_twi, LIS3DH_ACC_I2C_SAD_H, buf[0], 1, false); 
 
 This might not work as you intend. I will assume your WHO_AM_I string is a single byte, which also means that the remaining 6 bytes of your buf array is randomly initialized. You then proceed with nrf_drv_twi_tx(which is deprecated, by the way) for sending only the first byte of the array. If this what you intended to do? Also, is there a particular reason why you are using the legacy layer of the TWI driver? 
 You can read more about the available TWI functionality and usage in the TWI API Reference . 
 Best regards, Karl

52810, LIS3DH, i2c using TWI, got NRF_ERROR_DRV_TWI_ERR_ANACK while calling nrf_drv_twi_tx

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