Something interesting!
Just was poking around a working -02 board and noticed that DMAGO was located at 3000h. Had the Fluke manual open to the RAMP test and figured I had nothing to loose by seeing if the RAMP test would toggle all the data lines and perhaps be a useful part of Asteroid testing. Lo & behold, doing RAMP (with LOOPING) at 3000h produces a 45 degree line running across the screen from above the upper left corner down to below the lower right corner in a continuous repeating sweep.
Now I shall probe the DAC and control lines to see if there is a simple frequency generated there that can be noted and used for future boards...
More in the future...but the RAMP test is cool, try it at home with your 6502 pod on a working Asteroids game. Now I'm going to try it on some semi-dead (working RAM/ROM but beepers) boards...
John :-#)#
At 10:48 AM 02/01/2004, John Robertson wrote:
Anyone want to work on these with me? I have a pile of Asteroids boards and I'd like to get a couple running. All have issues in their vector section - the idea is to automate the process somewhat (not as much as the 9100 can handle!) enough to enable someone that is moderately proficient with board repair to be able to have better procedures for Asteroids (and Deluxe as well).
I'm thinking of adding in the signature work from http://www.gamearchive.com/Video_Games/Manufacturers/Atari/signatures/ as a base to run after one does the simple RAM Rom ext tests of the existing Asteroids script. I would be happy to use an external SA device as most folks don't have a built in SA on their 9010s (I have a couple of these machines but haven't gotten around to using that feature).
Script Generator http://tech.quarterarcade.com/tech/CodeGenerator/Default.aspx is a great starting place, but can one insert existing code into it and then operate the generator?...
John :-#)#