rainer Posted September 12, 2023 Share Posted September 12, 2023 it was late... by accident i inserted the cpu + memory card in the wrong direction (both!!) on my Atari 400 on the memory card U17 (left down corner) was getting very hot. as this is a 32 kb ram expansion and the machine has 48kb, there should be 16k on board? but i dont find ram on the mainboard. for testing issues: should the 400 run without the ram card? i never tested this. is there still hope for my little 400? Quote Link to comment Share on other sites More sharing options...
ClausB Posted September 12, 2023 Share Posted September 12, 2023 There's always hope. It's difficult to test without a RAM board. But you could find a common 16K board for testing. As for 32 v. 48K, if you post photos, we can help identify it. Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 13, 2023 Share Posted September 13, 2023 There's +12V present on both cards and having it go to the wrong place could be a real problem. You'd probably have to find pinouts then work out where the +5 and +12 ended up. Just a guess but putting them back in the proper way then testing isn't likely to make them any worse. Running without RAM - any Atari can do so but the only way you could get any sense from the machine would be to have a diag mode cart inserted. Even then the cart would need to be able to do something without RAM (not sure if any exist) What could be done is something that sets screen colours and even a display that's in the ROM and maybe play some sound. It could be useful to find signs of life in machines with the memory taken out. Quote Link to comment Share on other sites More sharing options...
ClausB Posted September 13, 2023 Share Posted September 13, 2023 Yes, the data bus is at one end of the slot and power lines at the other. So 12V and -5V would have gone on some data lines. I'm guessing the hot chip was the data bus buffer. Quote Link to comment Share on other sites More sharing options...
adam242 Posted September 14, 2023 Share Posted September 14, 2023 I have an extra CPU card and 16K memory card I'd be willing to send your way for cheap, should you need them. PM me! 2 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted September 14, 2023 Share Posted September 14, 2023 Remember to send you broken cards to someone who will fix them. The Atari Parts exchange and repair network will keep us all going for milleniums 2 Quote Link to comment Share on other sites More sharing options...
ClausB Posted September 17, 2023 Share Posted September 17, 2023 On 9/12/2023 at 6:33 PM, rainer said: my little 400 Any update? Quote Link to comment Share on other sites More sharing options...
rainer Posted September 26, 2023 Author Share Posted September 26, 2023 No Update can anyone Test a 400 without RAM Expansion If it does anything? Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted September 27, 2023 Share Posted September 27, 2023 Where do you live at? Quote Link to comment Share on other sites More sharing options...
tep392 Posted September 27, 2023 Share Posted September 27, 2023 First, there is no RAM on the mother board on the 400 or 800. Without the memory card, the machines have no RAM. I tried my 800 with all memory cards removed, which should have same result as the 400 and got a blank greenish screen. It didn't do anything. I don't have a diagnostic cart to test. 1 Quote Link to comment Share on other sites More sharing options...
rainer Posted September 27, 2023 Author Share Posted September 27, 2023 i live in austria! i wonder why there is a mark "32 kb" on the card when it has 48 kb when the card is alive. where does the 16 kb come from? strange thing Quote Link to comment Share on other sites More sharing options...
ClausB Posted September 27, 2023 Share Posted September 27, 2023 7 hours ago, rainer said: I wonder why... Just post a photo and we'll let you know! Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted September 27, 2023 Share Posted September 27, 2023 16 hours ago, tep392 said: First, there is no RAM on the mother board on the 400 or 800. Without the memory card, the machines have no RAM. I tried my 800 with all memory cards removed, which should have same result as the 400 and got a blank greenish screen. It didn't do anything. I don't have a diagnostic cart to test. Yup, an 800 needs the os rom module and at least one 16k module to boot afaik. With a 400 you need the ram module inserted to boot up. As ClausB says post pics of what you are seeing on screen as well as the models in question. Quote Link to comment Share on other sites More sharing options...
rainer Posted October 5, 2023 Author Share Posted October 5, 2023 Good News! I get a new RAM Board. And Sally is alive and kicking. i added a USB Keyboard from lotarek... Works! How can i get a AV Out? Greetings 1 Quote Link to comment Share on other sites More sharing options...
rainer Posted October 5, 2023 Author Share Posted October 5, 2023 Good News! I get a new RAM Board. And Sally is alive and kicking. i added a USB Keyboard from lotarek... Works! How can i get a AV Out? Greetings Here a Pic of my dead RAM board 1 Quote Link to comment Share on other sites More sharing options...
ClausB Posted October 5, 2023 Share Posted October 5, 2023 Congrats! Yes, the board in the photo does have only 32K. Why do you say it had 48K? Quote Link to comment Share on other sites More sharing options...
tep392 Posted October 5, 2023 Share Posted October 5, 2023 It's pretty clear from that photo that one of the caps failed. Quote Link to comment Share on other sites More sharing options...
Houdini Posted October 6, 2023 Share Posted October 6, 2023 3 hours ago, tep392 said: It's pretty clear from that photo that one of the caps failed. Looks to me like all 4 electrolytic caps on the bottom row failed (C28,C25,C26,C27 from left to right) and leaked electrolyte all over the connector pins. That's not ideal. 😬 Quote Link to comment Share on other sites More sharing options...
BillC Posted October 6, 2023 Share Posted October 6, 2023 The failed capacitors are likely due to his installing the RAM board backwards, some ICs have probably failed as well. Quote Link to comment Share on other sites More sharing options...
+slx Posted October 6, 2023 Share Posted October 6, 2023 7 hours ago, rainer said: How can i get a AV Out? There are several ways to accomplish this: You can use the "UAV" board (which has a very long thread around here). It requires some soldering, but not a lot. I don't remember exactly but I think it needs an extra board to get audio out, at least if you want to be able to use cassette audio. Alternatively you can swap your CPU card for @tf_hh's SCCC card which has both the UAV and audio circuit on a redesigned CPU card that will accept "normal" non-Sally CPUs as well, can be used as a base to convert the machine from PAL to NTSC or vice versa and requires soldering of three wires for audio. (SCCC2 with Sophia-based digital video output might be available in the future.) For both you have to come up with a way to get the video out of the Atari. If you don't want to drill the case the easiest way is to remove the RF cable and route the new cable out through that hole. SCCC comes with a ready-made cable with a standard Atari monitor jack and for UAV I used a cut-off video cable with cinch connectors (above a certain age you usually have some of those in a parts bin from old video equipment). You also have to get the cable out of the RF cage by either drilling a hole in there or using an adjustment hole at the rear (which I am not sure all 400s have). There are probably some DIY versions around as well. If you buy the SCCC tf_hh also sells a 48K RAM board. He was (is) ABBUCs "hardware doc" and will install stuff on request if you send it to him (Germany). Btw, ABBUC is worth joining for any 8-bit user. Where in Austria are you based? An Austrian Atari meeting is long overdue! (Feel free to reply in German via PM.) Quote Link to comment Share on other sites More sharing options...
mimo Posted October 6, 2023 Share Posted October 6, 2023 (edited) SCCC from tf_hh is well worth the money, if you want DVI output that can easily be changed to HDMI then you could wait and see if there is another run of Sophia 2 from Simius Edited October 6, 2023 by mimo 1 Quote Link to comment Share on other sites More sharing options...
Peri Noid Posted October 6, 2023 Share Posted October 6, 2023 11 hours ago, rainer said: How can i get a AV Out? Here a Pic of my dead RAM board Get yourself a SCCC from @tf_hh and you'll have both S-Video and Composite out of it. By the way, this RAM cart can be fixed easily, it contains only common chips. Quote Link to comment Share on other sites More sharing options...
+slx Posted October 8, 2023 Share Posted October 8, 2023 UGV gibt's auch noch, dass sollte auf PAL-Geräten sogar lötfrei sein. (There's UGV as well which should be a solder-free Installation.) Quote Link to comment Share on other sites More sharing options...
johannesmutlu Posted October 10, 2023 Share Posted October 10, 2023 Speaking about ram upgrades for the atari 400,for what i,ve readed is that early atari 400’s only did had 4KB of ram and that later atari 400 systems did had 16KB ram installed,now comes the wuestion,if i want to upgrade my atari 400 with extra ram like 48KB,do i really have to solder extra wires to make it work or is that soldering only required for audio in and out for cassette tapes??? also i,ve readed that first models of the atari 400 did had a ctia chip for a maximum of 128 colorpallet while later revisions of the atari 400 did contain a gtia chip for a maximum of 256 colorpallet,is this true? May ask why as it could cause confusion among sellers and buyers for whether their capabilities and compatibilities with certain games, Not mention,many remodeled atari 8bit system do use their own os system,thus rendering more games to became incompatible with each other,may ask why,why didn’t atari just used 1 system rather then sneakingly upgrade them under the hud?? Now if only the atari XE,atari 800 or the atari 5200 was upgraded,it wouldn’t have caused that much confusion to anybody, but because of this,it does makes me wonder wich games do take advantage of the 256 colorpallet and the extra ram and wich games did not and wich games did require a certain os system to make them work??? as far as i know,it’s a mess and a mix match of trial and error among consumers to decide what to buy and as far as i do know theres no way to upgrade the system to increase compatibility with more games without moddifying the whole system,maybe in some cases, i ordered my atari 400 and i can only hope it’s the upgraded version with higher compatibility of certain games and also hope that it works anyways as it was untested,but it’s low price triggered me to buy it. only time will tell whether i do regret buying it or not, Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted October 10, 2023 Share Posted October 10, 2023 2 hours ago, johannesmutlu said: if i want to upgrade my atari 400 with extra ram like 48KB,do i really have to solder extra wires to make it work or is that soldering only required for audio in and out for cassette tapes??? There are 4 jumper wires required to be soldered between the cartridge port and the RAM connector. These are only for the RAM upgrade and soldering these jumpers will allow the Atari 400 to handle more than 32k of RAM. 48k of base memory will be possible and, if the proper board were to be made, 4096k of extended memory. (Currently, the Atari 400 can be upgraded to a total of 1056k of extended memory.) I have boards to upgrade a 400 to either 48k or 1056k here: https://www.tindie.com/products/5cfab/48k-memory-upgrade-board-for-the-atari-400/ https://www.tindie.com/products/5cfab/1056k-memory-upgrade-board-for-the-atari-400/ The instructions as to what jumpers to solder are here: https://www.digitpress.com/library/techdocs/atari_400_48k_ram.pdf Best Regards, Brian 1 Quote Link to comment Share on other sites More sharing options...
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