This is a simple way to program Atmel AT28C-style EEPROMs with an Arduino Mega.
There are two pieces: the Arduino firmware and the Python CLI.
- Wire up the Arduino as shown in the breadboard diagram below. Don't forget the 10kohm pullup resistor on the WE pin.
- Flash the firmware to the Arduino.
- Install pyserial:
pip install pyserial
- Run the Python CLI tool.
Read the first 20 bytes of the EEPROM:
python3 at28c_programmer.py -d /dev/ttyACM0 -r -l 20
Flash a binary file to the EEPROM:
python3 at28c_programmer.py -d /dev/ttyACM0 -w -f file.bin
- I soldered this whole mess onto a PCB shield for the Arduino Mega with a ZIF socket to avoid having to wire this constantly.
- This writes one byte at a time over the serial port. It is slow... If you have to flash huge binary files, you're probably better off with an off-the-shelf EEPROM programmer, but if you want to save $60, this will work for small files.
- The
-w
write command also supports a limit-l x
limit parameter. This will limit the writes to the first x bytes. Might be useful if your EEPROM binary file is padded with zeroes.