greggj Posted July 25, 2019 Share Posted July 25, 2019 Hi y'all, my GTIA is playing up in a strange way (see screenshot). I need a new one. The current one in the computer is CO14889-O1 Quote Link to comment Share on other sites More sharing options...
6BQ5 Posted July 26, 2019 Share Posted July 26, 2019 Brad @ Best Electronics has some. Try emailing him with "Atari" in the subject line. Quote Link to comment Share on other sites More sharing options...
Swami Posted July 26, 2019 Share Posted July 26, 2019 20 hours ago, greggj said: Hi y'all, my GTIA is playing up in a strange way (see screenshot). I need a new one. The current one in the computer is CO14889-O1 I think I bought a couple from B&C Electronics on ebay (user:myatari). 1 Quote Link to comment Share on other sites More sharing options...
masschamber Posted July 26, 2019 Share Posted July 26, 2019 I have a spare 5200 mother that was dead, there was damaged around the power switch, I pulled a pokey from it and it worked fine, but I'd sell the board for 5 plus shipping Quote Link to comment Share on other sites More sharing options...
greggj Posted July 26, 2019 Author Share Posted July 26, 2019 2 hours ago, masschamber said: I have a spare 5200 mother that was dead, there was damaged around the power switch, I pulled a pokey from it and it worked fine, but I'd sell the board for 5 plus shipping Sure, I live in the UK tho. Quote Link to comment Share on other sites More sharing options...
masschamber Posted July 26, 2019 Share Posted July 26, 2019 4 hours ago, greggj said: Sure, I live in the UK tho. Well that's the end of that then unfortunately Quote Link to comment Share on other sites More sharing options...
mattsoft Posted July 27, 2019 Share Posted July 27, 2019 I have a 14805 (NTSC) GTIA laying around that I'd be happy to ship to the UK (from the US). Don't know what that would do in your board tho...looks like you probably need the PAL GTIA instead. Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted July 30, 2019 Share Posted July 30, 2019 I wonder if these are symptoms that can be corrected with your existing chip, by using this adapter "fixer" by Simius, from @tf_hh? The "known buggy" GTIA was found only in PAL machines, mostly 800 XE. http://www.van-radecke.de/STUFF/tfhh_HW_info.pdf Manual here: http://www.van-radecke.de/GTIAFIX/Info_GTIA_Fixer.pdf 1 Quote Link to comment Share on other sites More sharing options...
greggj Posted July 30, 2019 Author Share Posted July 30, 2019 Interesting stuff @Nezgar. I almost wish I could just borrow it and test it out ? Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted July 30, 2019 Share Posted July 30, 2019 4 minutes ago, greggj said: Interesting stuff @Nezgar. I almost wish I could just borrow it and test it out ? I tagged tf_hh in my previous post, so he may chime in. You could also PM him to ask directly. If there's doubt, I'm sure he'd be open to testing it for you if you sent him the chip. I presume you are in Europe? He is in Germany. Quote Link to comment Share on other sites More sharing options...
greggj Posted July 30, 2019 Author Share Posted July 30, 2019 I'm in the UK, still in Europe ? 1 Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted July 30, 2019 Share Posted July 30, 2019 21 minutes ago, Nezgar said: I tagged tf_hh in my previous post, so he may chime in. You could also PM him to ask directly. If there's doubt, I'm sure he'd be open to testing it for you if you sent him the chip. I presume you are in Europe? He is in Germany. I´m here ? When I look to the pictures sent by greggj, them I´m pretty sure that the GTIA fixer won´t be the cure here. The grey patterns are absolute okay. And the manufacturing datecode of the GTIA is also none of the involved ones known as "China bad PAL GTIA". Further, my gut feeling would say that the ANTIC is the culprit, not GTIA. The GTIA only makes the TV signal & frames, which are okay, otherwise the screen would rolling endless or nothing really would be visible - but the screen itself (technically) is stable. The colour generation is fine. When I look at the first both pictures I would say, the MSC (Memory Scan Counter) of the ANTIC is bad. This pointer can hold at maximum 12 bits or 4 KByte address range and it´s used in the display list of ANTIC´s "program code". Maybe the highest of these 12 bits is defective, this would explain the mirror effects in the first picture or the "black hole" in the 2nd picture. So my tipp: Change ANTIC first. Good luck, Jurgen 1 1 Quote Link to comment Share on other sites More sharing options...
greggj Posted August 2, 2019 Author Share Posted August 2, 2019 Thanks guys, I replaced GTIA - it did not help with my issues. So just as suggested by others here - I need a new ANTIC chip Quote Link to comment Share on other sites More sharing options...
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