Tandy Radio Shack TRS-80 Model 1 Gaming on Original Hardware
0Earlier this month I obtained a Tandy/Radio Shack TRS-80 [Model 1] Computer, one of the 1977 Trinity of home computers. The TRS-80 was originally more popular than the Apple II or Commodore PET and sold far many more units than Tandy Corporation expected it to sell. It was discontinued at the end of 1980 with the introduction of new limits by the FCC on the emission of RF noise.
The TRS-80 was not particularly known as a gaming machine, but there were hundreds of games written for it. Games came on cassette tape and later floppy disk. Most cassette-based games require a machine with Level II BASIC and 16KiB of RAM, which is what my system has. Many games focused more toward the TRS-80 Model III or IV can still be run on a Model I with 48KiB and disk drives.
The graphics capabilities of this system are extremely modest. There is no color and per-pixel addressable graphics have an effective resolution 128x48 pixels. Apple or PC Speaker-like audio can be heard via the cassette output jack. Input usually keyboard only, which is how I am playing these games and why I sucked so hard. The Z80 CPU runs at 1.77MHz, which is slow even by 8-bit standards.
For this video I picked four famous or impressive games. Dancing Demon was a very popular piece of entertainment software for the TRS-80. Frogger and Zaxxon are very impressive and officially licensed ports. Frogger and Zaxxon both implement countdown timers telling the user exactly how long the program has to load. I edited out most of the counts and loading. Sea Dragon is another game which may have been more impressive on other systems, but it is pretty amazing it works as well as it does here.
The TRS-80 Computer had a special display you can purchase, but it also could be connected to a home TV via an RF adapter. However, the 64-column text mode used an effective 384x192 resolution, which would make the text a bit difficult to read on a home TV. (You can see the 32-column text when the Dancing Demon program announces "Let the show begin"). The Power, Video and Cassette connectors on the TRS-80 all use 5-pin DIN connectors, and I used a DIN to composite video cable to get the signal from the computer.
As the computer uses a composite video connection, I figured it would be quite possible to capture a high quality image via my Datapath VisionRGB E1s as I did with the Apple II once I eliminated its color burst signal. And with a component to VGA cable and then a VGA to DVI adapter, I was able to get the image. The signal required a fair bit of tweaking before I could get text across the screen without shimmer and to reduce video noise. I do not believe anyone else has uploaded a capture of similar quality to Youtube from original hardware.
When the system is loading from cassette or drawing graphics with text, there may be some phase shimmer. This appears to be normal. Also, sometimes graphics will show random flickery lines, this is also normal as the CPU and the video display hardware fight for RAM access.