Updating (or downgrading) a firmware is done by unpacking the update zip file to the root directory of the microSD card (from a PC). Then insert to the M4 and powercycle the CPC/M4 board, after about 20 seconds it should be updated. Verify with |version command.
Latest firmware version can always be obtained via |upgrade command (no need to use PC, as long as CPC is setup to the internet).
'''Please notice, on M4 boards shipped after 2016-09-01:'''
Due to a new flashchip on the wifi-board, do not use firmware versions lower than v1.0.9. If done by accident, please use v1.0.9 and upwards to restore it.
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