OK64 : The OK 8-bit computer.

I decided to make my own “fantasy” computer, based on my experiences with the excellent Pico-8.

Download version 1.02 (September 2022) from here:

latest updates:

  • Sound output now uses SDL. Works on both mac/win
  • Bugfixes, rewrites
  • Drop programs with mouse

Here’s the deal:

  • MOS 6502 processor clocked in at 0.985 mhz (PAL)
  • SID chip (registers at $FF20)
  • OKVC (OK Video chip) registers at $F000-$FFF0)
  • 64K of program memory (pram)
  • 1mb of video memory (vram), accessible through pram registers
  • 256×256 8-bit VGA output (custom palette of 24-bit RGB 256 colors)
  • The OKVC has several built-in methods for fast drawing of primitives
    • Draw lines
    • Pixels
    • Circles (filled)
    • Triangles
    • Blitting (copying) of image data within vram, acts as sprites
    • Clearing
  • Combining the 0.985 mhz MOS 6502 with a very fast video chip will probably yield unexpected results!
  • I’m no hardware wiz, but I’m hoping that this computer could potentially be built IRL

If you have questions / suggestions on topics regarding the OK64, please check out the TRSE facebook page and/or contact me! If you’d like to try out the OK64, then the emulator (version 1.02 for windows) is currently included with TRSE, and is bundled together with 3 example projects:

  • The KOS (OK Operating system)
  • Standard tutorials with 5 examples
  • The OK Computer – a demo for the OK64 released in the “Wild compo” at Revision 2020.
An example of the OK 64 in action. Here, several TRSE Pascal programs are being compiled to assembler before being executed.