Troubleshooting an Atari 800XL that loads cartridges, but won't boot to Basic

[Beeblebrox]

1 minute ago, peco de guile said:

ah, sweet.  I went and looked for one in the States, but to no avail.  

Would this DRAM tester also be useful in testing RAM in other vintage computers?  I have a C64, C128, Atari 520st, and Amiga 500 to eventually look at. 

@peco de guile   Check out the listing again as it lists all the chips it can test. So AFAIK it will cover all 16-pin 8-bit computer DRAMS. Not sure about Atari ST or Amiga.

[TGB1718]

11 minutes ago, Beeblebrox said:

Not sure about Atari ST or Amiga.

It will do max 256K bit chips found in 520ST and 1040ST

[peco de guile]

Awesome, I'll order one. Thanks guys!

[_The Doctor__]

PIA comes into play here. I'd think that would be a common point.

[flashjazzcat]

Thread bumping time again?

[peco de guile]

Haha!  I don't mind the bump.  The project has been at a standstill since last summer.  

I purchase an Atari 7800 and 5200 to try and swap chips. I did swap the chips that had the same number codes on them, but it didn't fix anything.  Then I bought a oscilloscope that Adrian Black reviewed on his channel but never dedicated the time to learn to use it. In my defense, some IRL stuff went down and made things more difficult.  

But that's where the project left off.  The 800xl is in a plastic bin still disassembled.  

 

I don't remember is the 5200 had a PIA chip in it or not, but if it did, I think I tried it. 

I certainly don't mind rejuvenating this effort though, if there are more thoughts on what could be wrong.  So maybe I'll double check that I swapped the PIA...