Cromemco System 3 computer

The Cromemco System Three is a Z-80 based computer. Which is nice, because I always wanted to learn Z-80 (this is my second Z-80 computer, the other one is a MSX2).

But What I like about the Cromemco is how well-built it is. I love it.

The computer is that not big, but it is a very heavy computer.

At the moment I don’t have the needed cables to test it. If I can’t find them, I might be able to build them myself (or not). If manage to get the cables, and provided that the computer works, I promise to write a game or something for it 🙂


Cromemco System Three

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VChar64: character editor for the Commodore 64

c64logoI started to code a unicycle game for the Commodore 64. The first thing that I realized was that I needed an game editor, so I started to code one: VChar64.

Today I released v0.0.1 which has basic functionality but the functionality that it has, just work. You can download it from here:


  • Imports raw, PRG and CharPad file formats
  • Exports to raw and PRG
  • Basic editing functionality: Rotate, Invert, Clear, Shift left/right/up/down
  • Multiplatform: Win, Linux and Mac


Coding for the Commodore 64: What changed in the last 25 years


I stopped developing for the Commodore 64 in 1993. Since then a lot has happened:

Back in late 80’s ~ beginning of 90’s:

  • I did all my coding using the Commodore 128’s MONITOR command
    • That means no text editor, no compiler, no linker. Similar to the command that used to be in DOS
  • Since I didn’t use a text editor, I put all my comments in a notepad (I still have that notepad somewhere)
  • I used the Commodore 128’s SPRDEF as the Sprite editor
  • I used my own character editor called vchar… (later I created a similar one for DOS and Linux)
  • I did some basic graphics using a graphics editor… but I can’t remember which one
  • I didn’t know any other C64 developer, so I did everything kind of isolated
    • My sources of information were Commodore Magazine, Tu Micro Commodore and some books
    • I reversed engineer some games / demos in order to learn tricks
    • I had a 300 bps modem but I didn’t find any good C64 BBS
    • I did some cracks for a local company that was “publishing” (AKA pirating) games. In exchange they were providing me games. To put things into perspective it was impossible (I mean IMPOSSIBLE) to get original games in Argentina back then.
  • I knew some basic tricks like how to use more than 8 sprites, how to open the top and bottom borders, some raster effects… but nothing very advanced.
  • I loaded all my programs / games using the disk drive, which was much faster than the datasette, but still very slow
  • I had a fast-loader cartridge to accelerate the disk drive loading times. It also had a rudimentary MONITOR.
  • Although Argentina was using the PAL-N standard I had a NTSC Commodore 128. In Argentina we also had the Argentinean Commodore, called Drean Commodore, which was a PAL-N machine assembled in Argentina

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