Uploaded December 2025 | Updated September 2026, 3 weeks ago
What's the least amount of computer that you can successfully play Zork on? I decided to try it on a 4-bit CPU, the Intel 4004. I had already build a 4004-based Single Board Comptuer a few months back; all I needed to do was to extend that design to include more RAM and then write a Z-Machine for it. Writing a Z-Machine for the 4004 is no simple task, with the limitations of a 4-bit CPU. For example, accessing the amount of RAM required to play zork required extending the address bus with three additional shift registers, and a simple memory read takes a dozen or more instructions with this approach. Nevertheless, I was able to play Zork with an average execution time of 15 seconds per move. It's not fast, but it's playable. For more Vintage Computer Projects, see smbaker.com/.
Find the source code on github at github.com/sbelectronics/4004-zork.
What's the least amount of computer that you can successfully play Zork on? I decided to try it on a 4-bit CPU, the Intel 4004. I had already build a 4004-based Single Board Comptuer a few months back; all I needed to do was to extend that design to include more RAM and then write a Z-Machine for it. Writing a Z-Machine for the 4004 is no simple task, with the limitations of a 4-bit CPU. For example, accessing the amount of RAM required to play zork required extending the address bus with three additional shift registers, and a simple memory read takes a dozen or more instructions with this approach. Nevertheless, I was able to play Zork with an average execution time of 15 seconds per move. It's not fast, but it's playable. For more Vintage Computer Projects, see smbaker.com/.
Find the source code on github at github.com/sbelectronics/4004-zork.
