PET 2001 Emulator on an STM32duino
PET 2001 emulator is running on the STM32F103 BluePill development board, little slow but working perfectly fine.
After 43 years of the release of PET 2001 from Commodore International, it has been famous among developers to recreate it, which is not an easy task. There have been many projects on Commodore's Personal Electronic Transactor (PET) microcomputer to clone the Commodore PET-2001 and recreate it with an FPGA. In this, Bjoern Quentin shows PET 2001 emulator running on the STM32duino (BluePill) development board.
Quentin started writing the code in Rust and some inline assembly language, which is available on the GitHub repository. The main idea was to test the video output of the STM32duino (STM32F103 BluePill) while the PET emulation became a secondary target. Its video output is displayed via a composite video as demonstrated in the clip below, which is “probably not perfect and definitely pretty slow”.
The emulated disk drive uses GD25Q64CSIG, which is a 64Mb SPI NOR Flash. This flash memory has a read speed of up to 120MHz and supports a higher data transfer speed of 240Mbit/s for Dual SPI and 480Mbit/s for Quad SPI. This SPI NOR Flash is used to save / load programs.
It uses a matrix keyboard with eight select lines and nine data lines plus the shift keys. The keyboard mapping in the code will look different because of the soldering of wires.
In Quentin's video, you can see the PET 2001 emulator running on the STM32F103 BluePill board while it might take up some time, but the emulation still works.
Abhishek Jadhav is an engineering student, freelance tech writer, RISC-V Ambassador, and leader of the Open Hardware Developer Community.