Acceptance criteria:

• The ability to set the time with a star command (maybe *TIME, or split into *DATE and *TIME)
• The ability to read the time with a star command (maybe the same command, no parameters)
• Time can be set and read using MOS api calls
• Time can be used in FatFS as a timestamp

Nice to have:

• Check whether the EZ80F92 has a RTC (yes, but not fully plumbed in - see comments below)
• Check whether the ESP32 has a RTC (yes)