An early prototype below. Using a trusty Arduino Nano/Pro Micro/Something-or-other clone as the programmer here to write to 28Cxxx EEPROMs. There’s an 8K EEPROM on the left. The 16 address lines are provided by two 595 shift registers in the middle. A few control lines and 8 data lines are connected directly from the Arduino.
After some success writing a few bytes as a test. I built a more permanent version below and started to use Mario Keller’s Meeprommer python script to write ROM data. Here’s the Meeprommer github link.
More homebrew 6502
Part 3 : Memory map, address decoding and adding a ROM
Part 4 : Building an EEPROM programmer