How to Build a MiSTer CoCo

The Mr CoCo is a Tandy Color Computer 3 clone that runs on the MiSTer system.

CoCo Clones Quick Reference

Using just one file copied to the MicroSD card on the MiSTer system, you can own an accurate representation of the popular Color Computer 3.  Add thousands of virtual floppy disks from the CoCo archives and you’ve got yourself a CoCo Christmas all year long from here on out.  The experience is surreal.

Now before you build this awesome CoCo clone, let’s get a grand picture of things…

Some notable features

  • Ported from the Matchbox CoCo core, the most accurate and capable all-hardware Tandy Color Computer 3 clone available.
  • Very compact
  • Employs Greg Miller’s cycle-perfect 6809 core with .89, 1.79, 3.58, 7.16 and higher Mhz.
  • Selectable 128KB, 512KB, 1MB, 2MB of RAM
  • Joystick/gamepad/controller support as of 2/5/2019
  • Dynamic HDMI video with stereo sound
  • 512+ colors
  • Up to 640×480 resolution
  • Separate stereo jack for all audio generated by the system.
  • USB keyboard and mouse support
  • MicroSD card holds thousands of virtual disks/drives, OS-9 images.
  • Runs OS-9/NitrOS-9 and Sock Master demos like a boss.

Summary of the main parts

  • Terasic DE10-Nano FPGA board (Terasic) (Digi-Key)
    • What does the Terasic DE10-Nano do? It has chip real estate space that we will program to become a 6809 CPU, GIME, 6821 PIA, 6551 ACIA, AY-3-8910, and much more!
    • Where can I get a Terasic DE10-Nano? From the Terasic web site, Amazon, ebay, and many other sellers, with the average cheapest price being about $130 through Terasic and Digi-Key.
  • Get the FPGA core
  • Plastic case: several are currently being offered in the shop on this site.
  • USB keyboard
  • USB mouse (if you don’t have a real CoCo joystick)
  • HDMI monitor or TV
  • FAT32 SD card with your favorite CoCo .dsk images and OS-9 images.
  • DE10-Nano JIC Configuration File

Mr CoCo runs as a CoCo clone “core” on the MiSTer system which is basically the DE10-Nano and a few files written to the Nano’s MicroSD card.  This is an all-hardware clone, meaning that everything runs from a single FPGA chip, with the SD card being used to hold the support files needed to emulate floppy disks, ROM paks, tapes, etc.

Learn more about the MiSTer system and how you could literally own all of the vintage computer systems you never could afford as a teen, and they are spot-on accurate unlike most of the emulators out there.  This is not an emulator but rather actual chip logic that runs without compromise.
USB joystick/gamepad support added on 2/5/2019

Author: Roger Taylor