I’m excited to announce a very cool project for retromaniacs:
- A real 8 bit microprocessor connected to Arduino or Teensy
- Build your 8-bit microprocessor project as simple as writing Arduino Code.
- Make system hardware changes quickly by modifying Arduino code.
- Works with Arduino Mega (cheap, easy) or Teensy 3.5/3.6 (faster, more memory).
- Open source hardware and software (see below for links).
- Easy to build kits available for sale.
Completed RetroShields:
My goal is to build a daughtercard for every microprocessor out there. This is what I have completed so far.
| Microprocessor | Emulated Hardware | Software |
|---|---|---|
| Intel 4004 | printer + kbd | Busicom 141-PF Calculator (www.4004.com) |
| Intel 8031 | 8031 + UART | PAULMON2 (Paul Stoffregen) |
| Intel 8085 | 8085A + 8251 | MON85 (David Dunfield) |
| MOS 6502 | Apple-1 (6502+6521) KIM-1 (6502 + 6530) |
MON,BASIC,Cassette (Steve W) KIM-1 (MOS Technology, Inc) |
| Motorola 6803 | 6803 + 6850 | Bill Beech’s 6800 Monitor Code |
| Motorola 6809 | 6809E + FTDI | Simon6809 (Lennart Benschop’s monitor modifed by Erturk) |
| RCA 1802 | 1802 + UART | MCSMP (Charles J, Yakym) Tiny BASIC (Tom Pittman) RCA BASIC3 (Ron Cenker) |
| Signetics 2650 | 2650 + UART | Signetics PipBug M20 Monitor Code |
| Zilog Z80 | Z80 + 8251 | Microsoft Basic (MSFT, Grant Searle) EFEX (Mustafa Peker) |
Arduino Mega 2560 Features:
- ROM : >200 KB
- RAM : ~6 KB (2KB left over for Arduino system sw)
- Microprocessor runs at about 100~200kHz.
- Peripherals: UART, PIA, Timers, etc. (emulated by Arduino)
- Arduino Shields can be used to add new features.
Teensy 3.5/3.6 Features:
I built an adapter board for Teensy so we can get more RAM and faster clock speeds. Bonus is we get to use the same Arduino IDE for code development:
- Microprocessor runs at 1.00+ Mhz.
- RAM : 256 KB
- ROM : >512 KB
- Provides 3.3V<->5V level shifting
- microSD slot (can be used to emulate disk drives)
- Peripherals: UART, PIA, Timers, etc. (emulated by Teensy)
Design Files
All hardware and software is open source.
Upcoming microprocessors:
I’m currently working on the bold highlighted processors.
- Intel: 8008, 4040, 8080, 8088
- Motorola: 14500B (1-bit ICU), 6800, 68008
- National: SC/MP (INS8060)
- Signetics: 8X300
- Harris HD6120 (PDP-8)
- Fairchild: F8
- Texas Instruments TMS9900
- Commodore SID
- EEPROM Read/Write
Let me know if you want anything else to be added to the list.
Kit/PCB Sales
- Kits are available on 8BitForce’s Store
- your purchase helps support more microprocessors
License Information
- Copyright 2019 Erturk Kocalar, 8Bitforce.com
- Hardware is released under Creative Commons ShareAlike 4.0 International.
- Software is released under the MIT License.
- Distributed as-is; no warranty is given.
- See LICENSE.md for details.
The Force
2020/11/02:
RetroShield 4004 is released w/ Arduino code that emulates Busicom 141-PF calculator running the original ROM images.
| 6502 | 6809E | Z80 |
|---|---|---|
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| 1802 | 8031 | 8085 |
|---|---|---|
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| 2650 | 6803 | 4004 |
|---|---|---|
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