jorevall Posted March 14, 2006 Share Posted March 14, 2006 Hi, Has anybode tried this SIMM based memory upgrade for any 8bit ATARI? http://www.a8maestro.com/atari/info/memory/simm1meg.htm If so, did it work well? Best regards, Freddie Quote Link to comment Share on other sites More sharing options...
Rybags Posted March 14, 2006 Share Posted March 14, 2006 I'd love to try one. But better step-by-step instructions and illustrations/pictures are needed. I have about 50 old 30-pin SIMMs and 20+ EDOs kept for the purpose of upgrading old machines like my 800XL, 130XE, and Amiga 500. Quote Link to comment Share on other sites More sharing options...
Mathy Posted March 14, 2006 Share Posted March 14, 2006 Howdy Guys Nope, but I tried this one: http://www.holyoak.com/atari/8bitcomp.html It runs great on my XEGS. I guess I'm having problems with a bad Phi2 signal on my 800XE. greetings Mathy Quote Link to comment Share on other sites More sharing options...
MEtalGuy66 Posted March 14, 2006 Share Posted March 14, 2006 Hi, Has anybode tried this SIMM based memory upgrade for any 8bit ATARI? http://www.a8maestro.com/atari/info/memory/simm1meg.htm If so, did it work well? Best regards, Freddie Heh. No I havent tried any of those upgrades, but Ive used SIMMS to do many atari upgrades when DIPs werent available. All you have to do is hook the adress and data lines appropriately, and pay attention to the type of refresh scheme of the chips you want to use (be they on SIMMs or otherwise), versus the standard atari refresh scheme (eg. CAS before RAS or vice versa), in fact alot of the newer memory will actually refresh itself, which makes the design of the upgrade less critical, and more reliable than with older, pin-compatable RAM. And... Since both SIMMS and DIPS are well documented in data sheets available from just about every RAM manufacturer under the sun, it's not rocket science. heh. Quote Link to comment Share on other sites More sharing options...
jorevall Posted March 14, 2006 Author Share Posted March 14, 2006 Howdy Guys Nope, but I tried this one: http://www.holyoak.com/atari/8bitcomp.html It runs great on my XEGS. I guess I'm having problems with a bad Phi2 signal on my 800XE. greetings Mathy I'll presume you meen the Van Nisselroy? Quote Link to comment Share on other sites More sharing options...
jaybird3rd Posted March 14, 2006 Share Posted March 14, 2006 Howdy Guys Nope, but I tried this one: http://www.holyoak.com/atari/8bitcomp.html It runs great on my XEGS. I guess I'm having problems with a bad Phi2 signal on my 800XE. greetings Mathy According to the documentation, that particular upgrade still has some bugs. Does anyone know if that's still the case, or is that old news? Quote Link to comment Share on other sites More sharing options...
Mathy Posted March 14, 2006 Share Posted March 14, 2006 Howdy Jorevall I'll presume you meen the Van Nisselroy? That's the one. Please also read the next message. Greeting Mathy Quote Link to comment Share on other sites More sharing options...
Mathy Posted March 14, 2006 Share Posted March 14, 2006 (edited) Howdy Jaybird3rd According to the documentation, that particular upgrade still has some bugs. Does anyone know if that's still the case, or is that old news? Since it's my upgrade, I should know. :-) The upgrade works very well in my XEGS. In the 800XE, I'm having timing problems. Probably due to a "Mexico CPU" (bad Phi2 signal). I've cured most of the timing problems, by recreating a new Phi2 signal from the existing Phi0 (yes, zero) signal. I still have some timing problems, but I guess/hope they wil be gone, once I put the rest of the computer on the new Phi2 signal too. (At the moment the upgrade and the rest of the computer are running on two different clock signals). Problem is, I haven't done anything on the Atari in over a year. And I haven't looked at the upgrade even longer. Mainly because I couldn't find anybody who was willing to test the upgrade in his (or her) XL/XE. Greetings Mathy PS for the new Phi2 signal you need a 74LS74. Edited March 14, 2006 by Mathy Quote Link to comment Share on other sites More sharing options...
lotharek Posted March 19, 2006 Share Posted March 19, 2006 (edited) The best solution to be the owner od 8bit atari equipped with 1mb simm upgrade is solution made up by PAsiu - polish electonic. I`ve expanded great number of ataris and everywhere works just fine. All you need is programmed logic GAL chip, one 157 and 175 chips. and a lot of time.... :-) http://hardware.atari8.info/simm.php in a case of any problem don`t hesitate to mail me. i`ll try to help. btw: look at this http://www.piekary.net/~lotharek/inne/img/DSC02491.JPG or http://www.piekary.net/~lotharek/inne/img/DSC02490.JPG http://www.piekary.net/~lotharek/inne/img/DSC02458.JPG Edited March 19, 2006 by lotharek Quote Link to comment Share on other sites More sharing options...
Mathy Posted March 19, 2006 Share Posted March 19, 2006 Howdy Lotharek The best solution to be the owner od 8bit atari equipped with 1mb simm upgrade is solution made up by PAsiu - polish electonic. I`ve expanded great number of ataris and everywhere works just fine. All you need is programmed logic GAL chip, one 157 and 175 chips. and a lot of time.... :-) http://hardware.atari8.info/simm.php in a case of any problem don`t hesitate to mail me. i`ll try to help. Unfortunately, that site is in Polish. I don't understand Polish. So I can't figure out, how his upgrade works and if it is still fully compatible with the 130XE. greetings Mathy Quote Link to comment Share on other sites More sharing options...
carmel_andrews Posted March 20, 2006 Share Posted March 20, 2006 This is a very old upgrade, I remember it from the back end of the 90's, i even gave my o/s controller card u/g'd xe to a friend of mine with several sticks of 256k STe ram so he could do the mod for me, I no longer have that xe I do have a normal 256k XL though, i dont know what ram mod it is, as the ram mod came (built in) with the xl when i bought it Quote Link to comment Share on other sites More sharing options...
Gunstar Posted March 20, 2006 Share Posted March 20, 2006 (edited) That's the upgrade I was going to attempt on my 1200xl. But I was able get my hands on a RamboXL (there's a minor hack for the Rambo to make it XE/Antic compatible) upgrade from MEtalGuy66, so I'm going with it instead. My reason for this decision is that I'm attempting to keep all my 1200XL upgrades professionally made, my XE is the self-made hack upgrades. But now it seems I made the right choice if there are some timing problems possible with other machines besides the XEGS. Edited March 20, 2006 by Gunstar Quote Link to comment Share on other sites More sharing options...
lotharek Posted May 3, 2008 Share Posted May 3, 2008 it is compatible with 130 xe but You have to downgrade it to 64kb ram first Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted May 4, 2008 Share Posted May 4, 2008 I did the upgrade in a 1200XL and it worked well... but it's a mess to install because of the lack of clean mounting points. You can't get the address and data lines all from one socket so wires string all over the place. 1 meg is also too large to stay compatible. I prefer 512K SRAM. By the way, there is an error in that hand drawn schematic. Don't remember what is is but I can figure it out if you're still serious. Bob Hi, Has anybode tried this SIMM based memory upgrade for any 8bit ATARI? http://www.a8maestro.com/atari/info/memory/simm1meg.htm If so, did it work well? Best regards, Freddie Quote Link to comment Share on other sites More sharing options...
JamesD Posted May 4, 2008 Share Posted May 4, 2008 Howdy Lotharek The best solution to be the owner od 8bit atari equipped with 1mb simm upgrade is solution made up by PAsiu - polish electonic. I`ve expanded great number of ataris and everywhere works just fine. All you need is programmed logic GAL chip, one 157 and 175 chips. and a lot of time.... :-) http://hardware.atari8.info/simm.php in a case of any problem don`t hesitate to mail me. i`ll try to help. Unfortunately, that site is in Polish. I don't understand Polish. So I can't figure out, how his upgrade works and if it is still fully compatible with the 130XE. greetings Mathy There is a link to a pretty well draw schematic. Sadly there is no source logic provided for the PAL. Quote Link to comment Share on other sites More sharing options...
voy Posted May 4, 2008 Share Posted May 4, 2008 There is a link to a pretty well draw schematic. Sadly there is no source logic provided for the PAL. Here you are: http://hardware.atari8.info/simm/simmexp.jed ^^ Quote Link to comment Share on other sites More sharing options...
MEtalGuy66 Posted May 5, 2008 Share Posted May 5, 2008 Go look at the MIO thread. We are using a 16megabyte 30 pin SIMM and it doesnt compromise compatability at all. Doesn't use any PIA bits. Just 2 8-bit banking registers at $D1E0 and $D1E4, a single enable bit on $D1E2, and 256bytes of your memory map at $D600-$D6FF. (thats 65536 banks of 256bytes each.) This RAM is partioned and formatted into ram-disk(s) by the MIO firmware configuration menu, and it loads the handlers automatically from ROM. Quote Link to comment Share on other sites More sharing options...
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