As it is part of the specifications, we know that we should prioritize the activities related to the radio communication to allow the hardware team to progress on the design, so in this case, the first prototype must:
- Boot a minimal system on the target (empty main loop)
- Set up serial port 0 for logging
- Set up an SPI port to communicate to the radio chip
- Write the radio driver
- Set up the timer
- Write the main application to test the radio channel (sending raw packets at regular intervals)
This first prototype will already start to look like the final device, even if it does not know how to communicate with the sensor yet. Some test cases can already be implemented to run on a mock gateway, checking that messages are received ...