I have programmed an RFID reader: I can erase the list of all my authorized cards/tags, add them , validated if a card is authorized or not, etc ... Everything works fine.
my problem, is that as soon as I power off the Nano, everything is lost ! So I figured I could save the authorized list in EEPROM.
IDs read from the RFID tag are 12 bytes long that are transformed into a string for comparison, etc ... I have provision for a max of 50 tags (MyTags to MyTags, type = String).
even if the length is 12 bytes long, I want to store the last 10 bytes, as the first ones are always the same: that way, each tag's byte would be store as address xx0 to xx9 (I like when things are aligned ...). So 50 Tags X 10 Bytes = 500 bytes...it would fit in the internal EEPROM !
I am totally lost on how to do that !!!
I need help, to : - on boot, load the list of authorized tag's ID that are allowed (as MyTags to MyTags[49}) - When a button is pressed, re-write the whole list of who's authorized to the EEPROM
eventually, I want to use an external EEPROM (so it can be replaced when written/read too many times) but for now, if someone can help me with the internal one, I can probably figure out the external one !!!
Thanks in advance !