Is M501 necessary in the M502, M500, M501 initialization sequence? about marlindocumentation HOT 2 CLOSED

This was a requirement of UBL because it didn't know how many mesh slots were available in the EEPROM until the settings.load() function supplied the count. I did a phat update of the EEPROM code, adding a proper data structure, and now the M501 is not required for UBL to know how many slots it has!

However, this change is not in 1.1.8. It will be in 1.1.9.

from marlindocumentation.

I did a bit more searching, and it does seem that the documentation is wrong here.

Quotink Thinkyhead in this post

M500 followed by M501 should have no effect. You're only reading back the settings just written.

M500 writes the current settings (in RAM) to EEPROM, so M501 immediately after M500 only reads back what you just wrote.

So... maybe I'll submit a PR, but I'll let it hang here for a bit longer to get some rebuttals.

from marlindocumentation.