On-board logging

[blairfrandeen]

I would like to replace all of the print statements with log statements, and I would like the momobox to keep track of some basic on-board logging. Some thoughts on the logger:

• I need a switch to make the Pico read-only. As described here, the Pico can self-write to its own filesystem, or it can allow the PC its connected to to write, which is used for easily updating the code. The linked article suggests making a switch, and adding it to the boot.py file. I propose to add the following to boot.py:

import board
import digitalio
import storage

switch = digitalio.DigitalInOut(board.GP22)
storage.remount(mount_path="/", readonly=not switch.value)

Currently GP22 is the pin that detects whether an SD card is inserted. What the code above would mean is that the file-system would be read-only (able to update the code) if the SD card was not present. Since the SD card is required to use the momobox, part of updating the onboard code would be to boot the momobox with the SD card removed.

• I would want to minimize and limit the size of the logs, since the on-board memory is limited to 1 MB, and some of that space is already spoken for. I know that the python logging module allows for this to some extent, so I'll have to implement it.
• On the subject of the above, it would be useful to minimize the size of the log file by minimizing log messages; it's okay to be terse