Waveshare NRF52840 - Chapter 7. I2 C; Scanning Slave Devices; Read Data from BME280

NRF52840 Eval Kit User Manual
Vision: V1.0.1 Date: 2019.01.19 33 / 72
CHAPTER 7. I2C
In this chapter, we will learn about how to use the I2C interface of NRF52840. There
are three examples, which are used here: 006_I2C(Scan Device), 007_I2C(BME280),
008_I2C(MPU6050 3D COUBE)
SCANNING SLAVE DEVICES
It keeps scanning the slave device address of those devices which are connected to
I2C bus.
for(address=1; address<=TWI_ADDRESSES; address++)
{
err_code = nrf_drv_twi_rx(&m_twi, address, &sample_data,
sizeof(sample_data));
if (err_code == NRF_SUCCESS)
{
detected_device = true;
device_address = address;
NRF_LOG_INFO("TWI device detected at address 0x%x.",
address);
NRF_LOG_FLUSH();
}
}
The code will scan slave devices address connected and print them.
READ DATA FROM BME280
BME280 is a module from Bosch that supports sense environmental temperature,
humidity and barometric pressure.
Write/read function from Bosch: https://github.com/BoschSensortec/BME280_driver
int8_t user_i2c_read(uint8_t dev_id, uint8_t reg_addr, uint8_t
*reg_data, uint16_t len)