tjlazer Posted August 18, 2009 Share Posted August 18, 2009 (edited) I just got this 65XE that apparently has bad RAM, upon bootup I get the RAM/ROM test screen. The middle RAM blocks are almost all RED, only 2 are ok. I need to crack it open to look but I assume the RAM is soldered in on these right? Can a 320K upgrade be done to these like the 130XEs? Edited August 18, 2009 by tjlazer Quote Link to comment Share on other sites More sharing options...
Rybags Posted August 18, 2009 Share Posted August 18, 2009 (edited) Soldered = yes. I believe you'll always get good blocks there... that corresponds to addresses $5000-$57FF where the Self-Test ROM overlays. Strange that you'd get a result like that - my guess is that your RAM is OK but the address decoding is breaking down somehow (PIA, Freddie or somewhere else in the line). The failed area is where the 130XE banking occurs ($4000-$7FFF). Maybe try some tests of your own... startup with Basic enabled, don't worry about booting anything. ?FRE(0) Should be about 38K or so free RAM. 10 ?STICK(0),STRIG(0);" ";STICK(1),STRIG(1):GOTO 10 Try a joystick in each port, values should change when you move it about. Then get a graphical representation of your "bad" RAM: POKE 106,128:GR. 15 <enter> Should give you a blank graphics screen + text window, using some of the "failed" RAM. COLOR 1:PLOT 0,0:DR. 159,159 Draw a line - should be a clean diagonal. Edited August 18, 2009 by Rybags Quote Link to comment Share on other sites More sharing options...
tjlazer Posted August 18, 2009 Author Share Posted August 18, 2009 I can't get to BASIC. The self test screen comes right up when powered up. Quote Link to comment Share on other sites More sharing options...
Rybags Posted August 18, 2009 Share Posted August 18, 2009 Some 65XEs are essentially 130XEs with half the RAM not populated. It could be that you just have a jumpered connection that's come off, so it's not reading that area of memory properly. Maybe pull the board out and give it a look over. Quote Link to comment Share on other sites More sharing options...
lotharek Posted August 18, 2009 Share Posted August 18, 2009 Hello 1. nice monitor !! 2. memory chips desoldering at first ! , then sockets into the board. Later - memory chips - IHMO to avoid problems with refreshing at leat one must have different timing. (200ms) Quote Link to comment Share on other sites More sharing options...
tjlazer Posted August 21, 2009 Author Share Posted August 21, 2009 OK I opened it up and it looks like it is just a 65XE mobo, so I will just have to replace the chips? Can a 320K MOD be done to this machine? Anyone willing to do this mod for me and I will pay you? Would love to have a 320K Atari... Quote Link to comment Share on other sites More sharing options...
Rybags Posted August 21, 2009 Share Posted August 21, 2009 Like I said, I doubt the RAM chips have any problems. In that configuration, each chip supplies 1 bit of information to make up any byte read from any RAM address. So, if one or more chips goes bad, it should affect every address. But if you find someone with the expertise to do a 320 upgrade, then they'd no doubt be able to work out what your problem is anyway. Quote Link to comment Share on other sites More sharing options...
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