Garbled Video Display

[Badwolf]

800XL unmodified.  FujiNet v1.3, current firmware. Connecting to CRT using DIN to RCA cable. 

Some games I attempt to load (blue max 2001.atr) and I can see the boot screen while it loads.  After loading I get this garbled screen.  Other times when I load (using Blue Max 2001 as an example again) it will finish and I can hear the music, but the display is just blue. I can even click Start and hear the game being played.

  Other programs/games work.  Could be the game is just bad, but the results seem inconsistent. Antic/GTIA  chip going out?

 

Just curious if anyone has seen this type of video display before.

 

[foft]

Presume you are holding option to disable basic?

[xrbrevin]

hmm, displaying random characters could imply ANTIC is worth a check. it could be feeding duff data to the GTIA

[Badwolf]

1 hour ago, foft said:

Presume you are holding option to disable basic?

Yes indeed

[Beeblebrox]

I'd say antic chip is either failing, or there is a bad connection with one of it's legs. 

 

Can you upload a video (or upload it to YouTube and past the url here). 

 

 

[foft]

Gtia seems to be working. Antic character dma is working. Is disabling the os rom via the pia working?

[_The Doctor__]

Might be a couple of things

FujiNet Option Key use is a matter of timing for where when and how long you press it down to enable / disable BASIC

Post the actual .atrs you are using with your FujiNet so we can give it a whirl

Edited February 1 by _The Doctor__

[bfollowell]

Not quite the same as mine, since mine is more graphic than characters, but similar. I checked mine all out and swapping chips in and out shows ANTIC and GTIA as good and known good ones act the same in system. For mine anyway, I suspect a RAM circuit/delay line issues, or maybe a flakey/failing 4050. I've moved onto other projects and family life though, since a grand kid moved in with us and, unfortunately, my ailing 800XL has been moved to the back burner. I really need to get back to it soon.

 

Also, this machine is dead in the water other than displaying these screens. But to answer your original question, yes, I've seen screens similar to yours before.

 

 

 

 

[Badwolf]

I’ve already replaced the ram. Think I’ll swap out Gita and antic, although that wasn’t the fix for you. But I think it’s the next logical step for this box. 

[Badwolf]

On 2/1/2024 at 12:20 AM, _The Doctor__ said:

Might be a couple of things

FujiNet Option Key use is a matter of timing for where when and how long you press it down to enable / disable BASIC

Post the actual .atrs you are using with your FujiNet so we can give it a whirl

That’s a good point. I have a habit of not holding down option long enough for the blues screen to show. Usually programs still low but perhaps some are more sensitive to this than theirs. I didn’t even think about this possibility.