Help With Half - Working 800

[Paul Westphal]

I just can't figure this out. Game carts work on the 800 just fine ( except for basic ). The memo pad and basic screens are garbled. I HAVE tried different basic carts so it's not that. I have even tried different ROM and CPU boards to no avail. Any ideas? I have an extra non- working 800xl board laying around so I could swap some chips....any ideas are welcome HELP!

[fibrewire]

Pick a cartridge game that works. Turn off the atari and pull out all ram modules. Take one ram module and plug it in closest to the rom module. Turn on the atari. If the game works then that ram module is most likely good. Cycle through all ram modules until game does not turn on. If you find a module that doesn't work then you've found the problem. If all ram modules don't work with the game, then the cartridge you picked requires more than 16k. If none of the ram modules give you a problem, then it was most likely dirty contacts or bent slot connector in one of the other ram slots. Reseat all modules and see if basic works.

[+David_P]

I suspect it's the rear RAM slot. Since BASIC & Memo Pad use the top of RAM, a problem there may manifest like that.

 

Try pulling the rear RAM card & see if Memo Pad works. If yes, then swap the middle RAM card with the one that was previously in the rear. If that works, then it's slot #3. If, on putting the old Ram #3 into RAM #2 things go bad again, it's the RAM card.

[Paul Westphal]

That was it Fibrewire, Thanks! I forgot Basic and memo pull from the RAM card closest to the ROM. In the process I tested all the other RAM cards I had laying around and found out I had two others that didn't work. I'm so used to running into more complex problems, I forgot the simplest solution. I can now add a 800 to my ' for sale' list.