G'day Darrel,
I have done a bit more on this, and finally got some on screen debugging done.
What actually comes in is: 0,4,1,4,3,B,B,C,E,6 which I am sending off to EEPROM as 30,34,31,34,33,42,42,43,45,36 which is the ascii of the first lot, correct??
I have wondered how to send off to EEPROM 0,4,1,4 etc as 04,14, etc making only 5 bytes in EEPROM rather than 10 with half the space used.
Ending up with 04,14,3B,BC,E6 the decoded ascii for which are all sorts of things. Thus getting back to my first question, getting some sort of decimal number formula that could be used with pretty much any 10 input characters to produce unique values for each.
I am reading the serial numbers off RFID tags and want to be able to say that card with serial number 04143BBCE6 is user number 356 (or something easily digested)
As a follow up to that, it would be real good to say that card serial 3BBC67467C is user 1, card 0414BCCD65 is user 2 etc, up to only 7 users for each system.
Is this confusing you as much as it is me??
I have played with placing the data in fixed locations in EEPROM, like this. To program the cards in to the thing at first use: Location 1 holds the card serial number in the full 30,34,31, etc format. Location 2 which is 16 further down the eeprom holds the second card's serial. Location 3, another 16 further down holds the third card's serial etc...right down to Location 14 or so, which is the eeprom's maximum space.
If I could use the half length serial numbers, then I could hold twice the number of cards and therefore users as well as making it easier to compare a newly read card with memory to see if a valid card was read.
Boy, I'm starting to waffle now, it's getting late.
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