The challenge

The challenge for this chapter is to build a small application that communicates with the outside world via the serial interface introduced in the last chapter. It should expect to receive the commands "mag" for magnetometer as well as "acc" for accelerometer from the serial port. It should then be able to send the corresponding sensor data to the serial port in response.

This time no template code will be provided since all you need is already provided in the UART and this chapter. However, here are a few clues:

• You might be interested in core::str::from_utf8 to convert the bytes in the buffer to a &str, since we need to compare with "mag" and "acc".

• You will have to read the documentation for the magnetometer API and functionality. While the lsm303agr crate provides the API interface, the LSM303AGR datasheet details the sensor's magnetic field measurement parameters. See pages 13-15 for sensor characteristics and, importantly, pages 66-67 for the output register format.