ubersaurus Posted December 29, 2018 Share Posted December 29, 2018 I'm trying to prep my Apple II for Magfest, and noticed some unusual graphical problems when trying to boot games. This occurs off the cffa and the actual Disk II drive. The bottom quarter of the screen in gameplay is full of garbage characters, while the loading screens have random characters basically the whole way through. Anyone know what the problem could be? Or how I can best find out? I also got another error trying to load Dino eggs off the cffa. Not sure what that's about - I don't recall seeing it before. Still boots off the cracked disk, though? The cffa self test found no issues. Quote Link to comment Share on other sites More sharing options...
Aunty Entity Posted December 29, 2018 Share Posted December 29, 2018 Memory? Seeing as it looks reasonable stable across the bottom there? Quote Link to comment Share on other sites More sharing options...
Lee Adamson Posted December 29, 2018 Share Posted December 29, 2018 I believe there's a soft switch that turns the 4-line text area in hgr mode on and off. I think it's handled by the IOU chip, but I wouldn't swear to it. Could maybe be the MMU instead(?). My guess would be that something's not right with that, and it's not telling the video stuff to go full HGR mode so it's still pulling some junk out of the text page (which is probably being used for something else). Unfortunately, I'm too ignorant to suggest anything to fix it, other than to try reseating the IOU, MMU, and video chips. 1 Quote Link to comment Share on other sites More sharing options...
Keatah Posted December 29, 2018 Share Posted December 29, 2018 (edited) I'll second the softswitch mode of failure. But, the II+ doesn't have MMU or IOU chips. It's all discrete. Perhaps look around F14, F13, or things to do with the nearby LS257 or LS259 chips. Edited December 29, 2018 by Keatah Quote Link to comment Share on other sites More sharing options...
The Usotsuki Posted December 29, 2018 Share Posted December 29, 2018 C052/C053 softswitch Quote Link to comment Share on other sites More sharing options...
ubersaurus Posted December 30, 2018 Author Share Posted December 30, 2018 (edited) I did a diagnostic program and it said the rom and ram chips are all good, so softswitch does seem likely - someone elsewhere pointed out it looks like an issue with the text/graphic modes intermingling. Could it be B12? I can check the F14 and 13 chips too. Edit: forgot I already tried reseating f13 and f14 (and several other nearby LS chips) with no success. Edited December 30, 2018 by ubersaurus Quote Link to comment Share on other sites More sharing options...
ubersaurus Posted December 30, 2018 Author Share Posted December 30, 2018 Good news! I reseated B12, H14, and F14 (again). Apparently one of them was the culprit, because now the thing is working right again! Thanks all for your help. 1 Quote Link to comment Share on other sites More sharing options...
Lee Adamson Posted December 30, 2018 Share Posted December 30, 2018 Glad you got it working! Quote Link to comment Share on other sites More sharing options...
Keatah Posted December 30, 2018 Share Posted December 30, 2018 For The Win!! Quote Link to comment Share on other sites More sharing options...
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