RAM/ROM Replacement and Debug console for 6502-based computers



The ROMulator is a RAM and ROM replacement and diagnostic board for the Commodore PET, Apple II, and other 6502 based microcomputers. The ROMulator connects to the 6502 socket in your computer, and the ROMs to use are selected by a dip switch on the board. It allows you to view the memory of a running 6502 machine using the replacement RAM by halting the CPU and sending the memory contents over an SPI connection to a Raspberry Pi.

The ROMulator is open source, and the schematics and Verilog code for the ROMulator’s onboard FPGA are available at: