I've done - or at least started - a few retro porting projects in the past, with varying degrees of success. And currently I've a couple of projects that are WIP, so I've decided to bore anyone unfortunate enough to stumble unwittingly onto this blog with my trials and tribulations along the way.
My past projects, in approximate chronological order, include:
- Space Invaders (arcade) to TRS-80 Model 4/4P with uLabs Grafyx Solution hires board. This was more of a patch than a port, and I was mostly successful - at least under emulation. The TRS-80 is lacking the 120Hz interrupt required by SI, and I never quite got to chaining two 60Hz interrupts to emulate the effect. Unmodified, it ran at half-speed though. I really should go back and attempt to get it running full speed on real hardware.
- Tutankham (arcade) to TRS-80 Color Computer (Coco) 3. Again, more of a patch, initially, and it was running and playable except for two issues; the screen was rotated, and scrolling wasn't implemented. I started to rotate the graphics but technical issues with the scrolling rendered it effectively dead-in-the-water.
- Lode Runner (MSX) to TRS-80 Model 4/4P with uLabs Grafyx Solution hires board. Another patch, and 100% playable under emulation. However the required graphics bandwidth proved to be the game's undoing on real hardware, although George Phillips is currently attempting to rectify that problem.
- Tandy Invaders (TRS-80) to the Microbee. 100% reverse-engineered to produce a relocatable ASM file that can be built for TRS-80 or Microbee with a simple '.define'.
- Donut Dilemma (TRS-80) to the Microbee. 100% relocatable ASM file that can be built for the TRS-80 or Microbee with a simple '.define'. Thanks to Nick for the source!
The first is Donkey Kong (arcade) to the Neo Geo, and is documented in my NGPACE blog as it pertains to the subject of that blog - the Neo Geo. As of this entry, it's around 50% complete and looking very nice indeed! I've even run it on real hardware (NGCD).
The second, and the reason I decided to start this blog, is Lode Runner (Apple II) to the TRS-80 Model 4/4P with uLabs Grafyx Solution hires board - and the TRS-80 Color Computer (Coco) 3. That's right - I'm attempting to port it to two completely different machines simultaneously.
In my next post I'll give more of an introduction to this particular port, but in the mean-time you can read more about my history with Lode Runner on an old homepage of mine.