leech Posted August 17, 2020 Author Share Posted August 17, 2020 1 minute ago, Gunstar said: Quite a few demos, but other than that, there is Yie Ar Kung Fu and Bomjack file versions. There are a couple XEGS cart titles that the .xex versions of require 320K, instead of 256K, because they have enhancements; these include Commando+ and Mean 18+. The Last Word processor can use upto 320K. It can be utilized with SpartaDOS in a number of ways. Great, now I want to mod my XEGS... Actually kind of wanted to anyhow, just the RAM, and keep it fully composite. Interesting I was unaware of those. For Last Word / SpartaDOS, I have my modded 130xe, which has U1MB, Rapidus, VBXE, and Stereo Pokey. So there is that. Though if I'm going to do any typing, I much prefer the 1200xl keyboard for sure! Quote Link to comment Share on other sites More sharing options...
BillC Posted August 17, 2020 Share Posted August 17, 2020 12 hours ago, leech said: Yeah, I was thinking about the pickyback... anyone know if there are dram chips that are 512k instead? Couldn't you t hen just swap out the chips? 7 hours ago, Gunstar said: I have no idea if there are pin-compatible 512K dram or not, even on simm boards I have from PC's or ST's that were 1, 2, 4 megs, they were still using 256K drams. DRAM normally increases in multiples of 4 because each address pin is used for both column and row, so each address pin added allows access to 4 times as many memory locations. 1 Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 I am having a similar issue with a RAMBO 256 upgraded 1200XL and super video 2.1 upgrade as well. It boots into self test and passes the ram test. Holding down option just gets a scrambled screen as does option and select. Replacing the 32 in one board with a RAMROD XL EPROM boots to basic, but the keyboard doesn’t work. Holding option boots to the usual OMNIMON XL memo screen. Holding down option and select brings up OMNIMON XL. The keyboard works in both those modes. Carts work as does FujiNet. Leech, did you give up? Quote Link to comment Share on other sites More sharing options...
leech Posted January 2, 2021 Author Share Posted January 2, 2021 49 minutes ago, JGRAHAM2 said: I am having a similar issue with a RAMBO 256 upgraded 1200XL and super video 2.1 upgrade as well. It boots into self test and passes the ram test. Holding down option just gets a scrambled screen as does option and select. Replacing the 32 in one board with a RAMROD XL EPROM boots to basic, but the keyboard doesn’t work. Holding option boots to the usual OMNIMON XL memo screen. Holding down option and select brings up OMNIMON XL. The keyboard works in both those modes. Carts work as does FujiNet. Leech, did you give up? Sort of, there was mention of holding off until @bob1200xl was able to test something. Haven't heard back though and that was a while ago. I think we decided part of it was something peculiar with the board revision? Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted January 2, 2021 Share Posted January 2, 2021 3 hours ago, JGRAHAM2 said: Holding down option just gets a scrambled screen as does option and select. This symptom sounds like it could be the OS "thinking" BASIC was disabled, and placing MEMTOP and the display in what would otherwise be in the cartridge ROM area of the memory map (at the 48K mark instead of the 40K mark), but the BASIC ROM is not actually being disabled resulting in the display list reading data from the BASIC ROM instead of RAM... PIA either isn't outputting the right signal, or the MMU isn't... Was the 1200XL's original MMU replaced with an 800XL MMU as part of these upgrades? (Original 1200XL MMU does not support internal BASIC) Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 Yes, I used the MMU that was with the upgrade kit. I could try a spare I have from an 800XL. Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 The MMU was the problem. I didn’t have time this morning to see if I might have just put the old one back in by mistake. Anything is possible. I’ll check that later and post here. Anyway, it is working! Thanks Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 I’m happy to say I did not mix them up. The picture attached shows the original MMU (right) and the one I got with the kit. It looks like it was desoldered at some point. My MMU from a spare 800XL board works great. Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted January 2, 2021 Share Posted January 2, 2021 @JGRAHAM2 Thats great to hear it works! (And that it's no fault of your own eh?) Your replacement MMU is a programmable GAL16V8 so I guess it's possible it's either defective or Steve mistakenly programmed it with the wrong configuration - ie as a 1200XL MMU instead of 800XL... Good news is these are reprogrammable "workalikes". You could ask Steve for a replacement/exchange, or you could try erasing/reprogramming it yourself with the likes of a TL866. Or lastly, I could program and send you one - and would be interested to test the old one if you sent it heh. Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 47 minutes ago, Nezgar said: @JGRAHAM2 Thats great to hear it works! (And that it's no fault of your own eh?) Your replacement MMU is a programmable GAL16V8 so I guess it's possible it's either defective or Steve mistakenly programmed it with the wrong configuration - ie as a 1200XL MMU instead of 800XL... Good news is these are reprogrammable "workalikes". You could ask Steve for a replacement/exchange, or you could try erasing/reprogramming it yourself with the likes of a TL866. Or lastly, I could program and send you one - and would be interested to test the old one if you sent it heh. I have a TL866, so I could reprogram it. I just burned some OS EPROMs for my Ramrod XL 800XL. If you want to look at it, I could exchange with you, or could I pull an image from it and send it? I tried the original 1200XL MMU and it did not behave like the GAL. It just went to a blank screen while the GAL went to the Atari test screen. Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted January 2, 2021 Share Posted January 2, 2021 @JGRAHAM2 So interestingly, the pin with the solder blob on it is /IO - My notes say it's an output that goes to 74LS138, selects hw chips (Y0 - GTIA, Y2 - POKEY, Y3 - PIA, Y5 - CCTL) - so maybe it was damaged from too much heat when that pin was soldered... Anyhow, if you have a TL866 I would just try erasing it, and re-program it with this JED file which replicates the Atari XL/XE MMU (C061618): https://atariage.com/forums/applications/core/interface/file/attachment.php?id=477498 1 Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 2, 2021 Share Posted January 2, 2021 Thanks! Quote Link to comment Share on other sites More sharing options...
JGRAHAM2 Posted January 3, 2021 Share Posted January 3, 2021 Just an update. Steve responded very quickly, especially considering the holiday weekend. He is sending a new chip. Again, thanks for the help on troubleshooting the problem. Leech, I hope you get your issue resolved as well. Quote Link to comment Share on other sites More sharing options...
leech Posted January 3, 2021 Author Share Posted January 3, 2021 10 hours ago, JGRAHAM2 said: Just an update. Steve responded very quickly, especially considering the holiday weekend. He is sending a new chip. Again, thanks for the help on troubleshooting the problem. Leech, I hope you get your issue resolved as well. Thanks. We should figure out which revisions of the boards have the problem. Funny that the 1200xl wasn't around for very long, yet the two systems I have do have different revisions on them. Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted January 4, 2021 Share Posted January 4, 2021 1 hour ago, leech said: We should figure out which revisions of the boards have the problem. It was a bad GAL-MMU was in this case, not the board. Maybe others were also affected by bad MMU replacements. Quote Link to comment Share on other sites More sharing options...
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