2015-07-22 (W) RFID Authenticator

Programming was continued. Items from the To do list were completed in a logical order. Arduinos have a limited amount of non-volatile EEPROM memory which can be accessed through programs. EEPROMWriteAnything was studied and implemented so that a tag can be scanned and permanently remembered by the system. Permanent memory is vital since hard-coding tags is tedious and keeping tags locked in memory is important because continuous power cannot be guaranteed.

Code was written so the tag scanned before the first reset becomes the master tag. That means that people who program this on their own can download the program to an Arduino and immediately scan any tag they choose then press the reset button. From that point on that tag will be considered the master tag even if a new program is loaded to the Arduino. The only way to clear the master tag is to clear the EEPROM memory which can be done with Example code provided with the download of the Arduino IDE.

Tags labeled with the last character of their serial numbers

RFID Authenticator Arduino Code

To do:
  • Define necessities of code
    • Act like commercial version
      • Acknowledge master tag
      • Allow new tags to be recognized after scanning master key
      • Store new tags in EEPROM memory. Non-volatile
      • Pin goes high only when recognized tags are in place
    • Different pin goes high when unrecognized tag is scanned (tampered)
    • VERY first tag scanned becomes master tag
  • Make linkable list of parts

The rest of the posts for this project have been arranged by date.

First time here?

Completed projects from year 1.
Completed projects from year 2

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2015-07-21 (Tu)