Filed under: Retro computing

So, my first computer came from a dumpster behdind a business somewhere in North Texas. It was an Altos 580 and an ADDS Viewpoint 3a terminal. It ran CP/M and had a BASIC interpreter and a Pascal compiler. We didn't have the money when I was little to get an NES, but I really really wanted to play Super Mario Brothers. So I set out on my first programming project. Armed with a book on BASIC (the wrong flavor of BASIC, mind) from the library and my junk computer I tried to write a version of Mario in ASCII for my 80x25 dumb terminal display. I didn't get far before I had to learn more and more advanced programming techniques. That rabbit hole landed me where I am today, a Senior Embedded Sys^H^H^H^H A Weirdo. I never actually finished that project. When the NES eventually got cheap enough I got one, with the Mario/Duck Hunt combo cartridge.

Running htop:

I couldn't keep that computer. We had to move various times and I had to pair down my hoard of machines (garage sales in the late 80s and 90s were great) down to just the most essential. I've looked now and then for Altos 580s and ADDS Viewpoint terminals on the various auction sites, but never had much luck. The Altos is unobtainum, and the ADDS terminals go for a lot. Until I saw one for a price I could pay on Goodwill's auction site. I managed to snag it and I will say they did a great job shipping it. The protection for the CRT was quite good. It gave me a cursor when I powered it up, but I couldn't get it to respond to serial data or to transmit.

Logging into the ICM's vintage system menu:

The PCB inside was covered in bodge wires. I'm not actually sure whats going on with it. It seems stuck on 110 baud. Thats lower than my USB to RS232 converters will go, but at 300 baud you could at least see something happening. I started gearing up to debug the board when a set of 4 PCBs for the Viewpoint 3a landed on ebay. I snatched them up quick. Lo and behold the first one I tried worked. I could receive, but not transmit. Turns out this keyboard is a Keytronics with the dreaded foam and foil keypads. I got a set of replacements from TexElec. These are not fun to replace, but the replacement pads are great quality. This fixed the keyboard and now I was able to transmit and receive just fine.

I'm in

My ultimate goal is to build a homebrew Z80 CP/M computer to run with this when I take it to events. A replica of my original computing environment. Maybe one day I'll find another Altos 580, but they are frankly huge and I wouldn't have anywhere to put one right now. I might even try to finish that first project, an ASCII version of SMB. Maybe just the first level. This terminal has enough control codes to support curses well enough. Vim and htop run fine. Time will tell.

This website in lynx: