LITTLE TIME FOR 1130 PROJECT WORK THIS WEEK
With the testing and repair of many game consoles for the Digital Game Museum in prep for a big party they are co-hosting in Sunnyvale - the Atari Party - I didn't have much time to spend on my project this week. The party is an event on Saturday where the designers of Pong and of the trackball will speak, plus enthusiasts and collectors will have more than 100 machines there ranging from Arcade to game console and home computer.
DISK DRIVE EMULATION DEBUGGING
However, I did spend some time redoing the code for the disk drive emulator, removing the SD card library which seemed to trip up my use of the SPI link to communicate with the fpga. Almost ready to resume testing with this change to see how the SPI signals behave and the Arduino communicates with the 1130 fpga.
SELECTRIC 963 TYPE ELEMENT (1130 CONSOLE BALL)
I had a search on ebay looking for someone selling a golfball type 963 which is the arrangement used on the 1130 and S/360 consoles. It is BCD arrangement and has capital forms of letters on both sides of the ball. One was miss-listed as an APL ball and I was watching it when I found the seller had relisted it changing the description to "rare EBCDIC 963". I also noticed it had a 'buy it now' button for $30, which I jumped on. The ball I had been using was the same as the 963 except that it had lower case style letters on one side and upper case on the other. This alternative ball would produce funny output if the program used the lower case character code; that problem goes away with the 963.
I spent about two hours working on parts of the logic diagrams and in hand cycling some instructions. We thought we had a failure to debug, as one of the demo programs suffered a process check in a multiply instruction on the Connecticut machine but we couldn't reproduce the error to diagnose it.
GAME CONSOLE LOT FOR DGM DONATION
It was a large lot sold as not working/for parts and often goods sold like this can be put back into operation - especially when it is many units. The first box I began working on, an Atari 2600 console, seems pretty solid so far. I see the processor working, composite video entering the RF modulator unit but until I string up controllers, a game cartridge and a monitor to this, I can't check it out further.
However, the Atari 800 I tried next turned out to have had some parts stripped from it - which violates the spirit of 'for parts' in the description. I am willing to take the risk that a fix is impossible or too expensive, but wouldn't have bought a lot if it were "partially stripped junkers" because that has me paying to haul away someones trash. I hope this stripped machine is an anomaly, since most of them appear complete even if not currently working. Both of the Atari 800 models were stripped of RAM, but the model 400 and 800XL appear intact.
It is going to take me a bit of time to work through these machines, with the Atari consoles prioritized so that they might be used at the Atari Party this weekend at the Sunnyvale Public Library. After that, I will probably work on the Commodore 64 and 128 systems, then move to some of the others.
As of Wednesday I had four of the VCS/2600 consoles working well and was at work on the next one. Soon I will need to turn my attention to controllers, doing some repairs and cleanup to get them working well with the consoles.
By Thursday evening, we are up to six of the VCS - 2600 working well, plus two VCS 2600 Jr models that work very well except they produce PAL format video (European standard) rather than the US style NTSC. Hooking it to a NTSC television gives a black and white image with lots of buzzing rather than audio, but the game itself is visible and plays correctly. The museum will add a PAL monitor to its collection which will support these plus any other PAL versions of other consoles that may be donated.
The Atari 400 is working properly too, after sorting out the proper power supply and doing some cleanup inside. One of the problems affecting it is oxidation on the contacts of several game cartridges - a round of cleaning those should get everything humming along.
I ran into some problems with an Atari 5200 system, not sure what the problem is but it could be a bad RF modulator. This may be a system that requires parts to fix - put it aside until the Atari party at the Sunnyvale Public Library is over. I focused on testing and collecting power adapters and controllers for all of the consoles that are already working. Might look at an Atari 7800 if I get a few minutes.
The first batch of restored/tested consoles were delivered to the museum Friday night. I have plenty of controllers to get working properly, the 600XL, 5200, 7800 and a sears 2600 to work on, then I can dig into the remaining pile - three TI 99 computers, three Commodore 128 and 64 machines plus floppy drives, an Odyssey and an Intellivision console. All at a much slower pace as filler projects while I refocus on my own 1130 tasks.