This is a heads-up about a slight problem we just discovered yesterday and confirmed today on 2 different apps for D21G.
If you try to set the date of your internal clock with MCP7940.h library on the 31st of any 31-day month, you get some rubbish in your date and you have a fifty-fifty risk of stopping your program in the setup() part.
The internal clock works fine in displaying and calculating time and date on the 31st, though. So just avoid setting your clock on these 7 days in a year.
Hope this helps,
Didier DORGUIN, DG2R
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