Is there a mechanism to permanently store some information, such as a couple numbers, and have those numbers read after a power down and restart?
(I must be slow typing today)
Depends what your definition of permanent is. The EEPROM is only good for 20 years at 85°C or 100 years at 25°C.In most cases though, that should be sufficient
If I do that, how do I not substitute whatever's randomly in EEPROM at boot time until it has been written
QuoteIf I do that, how do I not substitute whatever's randomly in EEPROM at boot time until it has been writtenWell the key is that EEPROM memory unless written to by user program coding will not contain 'random' values, but rather all 0xFF bytes at every location. So your sketch in it's setup code can just read a specific address in EEPROM and if it contains other then 0xFF values then it can assume that was a saved new default value to use.Make sense?Lefty