Dragon 32 computer emulator

The Dragon was my first computer when personal computers started to emerge in the mid 80s and it is also one of the simplest to emulate. Other emulators exist, including XROR, but I decided to build my own as an exercise in RPi bare-metal programming. This project implements the software and the hardware needed to emulate a Dragon 32 computer. The goal was to run the emulation on a bare-metal Raspberry Pi (RPi) platform with some external peripherals. Development was done on a Raspberry Pi Linux distribution.

Project's Git repository for emulator running on Raspberry Pi Linux distro.

Project's Git repository for emulator running on Raspberry Pi Bare Metal.

Download project schematics PDF.



Breadboard stage with Raspberry Pi Model B.

Built onto a wire-wrap circuit board with Raspberry Pi Zero. PS2 keyboard and original (Circa 1984) Dragon 32 joystick plugged in on the left. Power supply, composite video, and audio outputs connected on the right.

Added SD Card reader

Front panel with SD card reader, joystick, and keyboard inputs.

Back panel with 5v power input, on-off switch, reset button, composite video, and audio outputs.

Block diagram of Dragon 32 computer with hardware peripherals implemented in the emulator. Hardware implementation includes 6-bit DAC, audio multiplexer, ADC joystick comparator, and keyboard matrix as a PS2 interface.