vattari Posted July 23, 2018 Share Posted July 23, 2018 Hello, I pulled out an 800XL that I had in storage which I have looked at before. On the underside was written “256KB and RS232”. Hoping this was a RAM and SIO upgrade, I opened it up and took some photos. The Satantronic RAM testing utility only recognises 48k and fails on some tests. Does anyone know about this particular Ram upgrade is (labelled “JWG 86” in the photo) or what the RS232 upgrade might be? TIA Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
BillC Posted July 23, 2018 Share Posted July 23, 2018 (edited) Hello, I pulled out an 800XL that I had in storage which I have looked at before. On the underside was written “256KB and RS232”. Hoping this was a RAM and SIO upgrade, I opened it up and took some photos. The Satantronic RAM testing utility only recognises 48k and fails on some tests. Does anyone know about this particular Ram upgrade is (labelled “JWG 86” in the photo) or what the RS232 upgrade might be? TIA Sent from my iPhone using Tapatalk This PCB is likely a variation of Claus Buchholzs' 256k upgrade for the 800XL. The ICD RamboXL, Wizztronics 256k, and Newell 256k were commercial versions, this one could have been done by a local users group. There are 2 versions of the ANTIC chip, this PCB appears to be a simpler version which will only work with the later? one. Support for the other version of ANTIC requires a couple extra logic chips. The first think to check would be the ribbon cable connection to the PIA chip, which you haven't shown, this is required for bank selection. The RS232 mod could be an internal R-Verter interface connected to the SIO port. Edited July 23, 2018 by BillC 1 Quote Link to comment Share on other sites More sharing options...
1050 Posted July 23, 2018 Share Posted July 23, 2018 While the pictured card could be the controller for extended memory upgrade there are no ram chips added to make use of the controller. No wonder it tests as standard 48K machine because that's what it is with a not right at all controller that should cause issues. A better picture would have included all the chip numbers on the controller board without leaving out the bank of ram chips for their numbers as well. Doesn't matter now, it can't work without piggybacking some extended memory onto those chips and attaching more wires between the controller card and the piggy backed extended memory chips. Not what someone knowledgeable would do is what I'm looking at. Gives me zero confidence in RS-232 side which is NOT here. Quote Link to comment Share on other sites More sharing options...
vattari Posted July 23, 2018 Author Share Posted July 23, 2018 Here are some more extra photos: Good assumption @BillC - this was part of a job lot I purchased from a former member of the Christchurch Atari Users Group. If the controller is in, but the RAM chips aren’t, would people suggest completely the upgrade or reverting to stock condition? Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted July 23, 2018 Share Posted July 23, 2018 Hi, I think somebody didn´t read the manual by Claus carefully enough I see the standard 64 KBit DRAMs soldered directly into the mainboard. No other DRAMs visible. When I´m remembering right, you have to remove the 64 KBit (4164 or similar) DRAMs and exchange them to 41256 DRAMs (256 KBit), which will result in 64 KByte base memory and 192 KByte expansion memory. All other wires etc. looks good - except the changed DRAMs. Today I wouldn´t recommend one of these solutions - most modern games or demos requiring a memory expansion need 256 KByte expansion memory. Second thing, the banking scheme of such solutions is also special, so another amount of programs won´t work. And you´ve to desolder all existing DRAMs. Just my 2 cents... 5 Quote Link to comment Share on other sites More sharing options...
Gunstar Posted July 23, 2018 Share Posted July 23, 2018 Hi, I think somebody didn´t read the manual by Claus carefully enough I see the standard 64 KBit DRAMs soldered directly into the mainboard. No other DRAMs visible. When I´m remembering right, you have to remove the 64 KBit (4164 or similar) DRAMs and exchange them to 41256 DRAMs (256 KBit), which will result in 64 KByte base memory and 192 KByte expansion memory. All other wires etc. looks good - except the changed DRAMs. Today I wouldn´t recommend one of these solutions - most modern games or demos requiring a memory expansion need 256 KByte expansion memory. Second thing, the banking scheme of such solutions is also special, so another amount of programs won´t work. And you´ve to desolder all existing DRAMs. Just my 2 cents... I would agree. It might even be the early Bucholz which did 8K banking instead of the later Rambo, etc. 16K banking scheme. Am I seeing two piggy-backed PIA's in those pictures?!? Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted July 23, 2018 Share Posted July 23, 2018 I didn't realize Claus's original upgrade implemented 8K banks. I only know of the "Quarter Meg" upgrade, which used 32K banks (switching the entire lower half of the base RAM). Only one PIA in the photos, anyway. 1 Quote Link to comment Share on other sites More sharing options...
ivop Posted July 23, 2018 Share Posted July 23, 2018 I only know of the "Quarter Meg" upgrade, which used 32K banks (switching the entire lower half of the base RAM). Wow, never new such an upgrade existed. Would be very nice to have a modern RAM expansion that switches the entire lower half, including page zero and the stack. Think porting FUZIX: https://github.com/EtchedPixels/FUZIX But also your GUI/kernel project would hugely benefit from such a banking scheme. 3 Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted July 23, 2018 Share Posted July 23, 2018 Wow, never new such an upgrade existed. Would be very nice to have a modern RAM expansion that switches the entire lower half, including page zero and the stack. Think porting FUZIX: https://github.com/EtchedPixels/FUZIX But also your GUI/kernel project would hugely benefit from such a banking scheme. I got around the problem. Page zero and the stack and no longer an issue... the issue is finding time. I could do with a RAM upgrade which arrests the clock. 3 Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted July 23, 2018 Share Posted July 23, 2018 Here's the original Quarter-Meg article, for interest: http://blog.3b2.sk/igi/file.axd?file=2017%2f4%2fQuarter_MEG_ATARI_800XL_256kB_RAM.pdf 1 Quote Link to comment Share on other sites More sharing options...
Gunstar Posted July 23, 2018 Share Posted July 23, 2018 (edited) I didn't realize Claus's original upgrade implemented 8K banks. I only know of the "Quarter Meg" upgrade, which used 32K banks (switching the entire lower half of the base RAM). Only one PIA in the photos, anyway. I didn't know it either until Claus mentioned it himself in a thread somewhere either here or on Atari Sector. These 32K banked memory wouldn't be compatible with most of the 16K banked 130XE and Rambo/Wizztronics/etc. type memories though, right? So basically no extended memory software we have today would work, right? Edited July 23, 2018 by Gunstar Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted July 23, 2018 Share Posted July 23, 2018 (edited) He doesn't appear to be a member over there, but on the other forum you mentioned Claus and linked to this article: https://www.atarimax.com/freenet/freenet_material/12.AtariLibrary/2.MiscellaneousTextFiles/showarticle.php?104 Anyway, I'll be very interested to see what he wrote here if a link is forthcoming. PS: no software which expects one size of RAM banking could possibly work with a different sized banking window unless the software expected that banking windows might be something other than 16K in size and were able to detect if this were the case. Claus writes that he revised his 32K window RAM expansion to use the 16K window scheme that Atari subsequently adopted. Edited July 23, 2018 by flashjazzcat 1 Quote Link to comment Share on other sites More sharing options...
BillC Posted July 24, 2018 Share Posted July 24, 2018 As the PCB has JWG 86 etched on it I would think this PCB is the later 130XE compatible version, it can be confirmed by tracing the circuit and comparing it to that described in the link below: https://www.atarimax.com/freenet/freenet_material/5.8-BitComputersSupportArea/7.TechnicalResourceCenter/showarticle.php?29 Quote Link to comment Share on other sites More sharing options...
Gunstar Posted July 24, 2018 Share Posted July 24, 2018 He doesn't appear to be a member over there, but on the other forum you mentioned Claus and linked to this article: https://www.atarimax.com/freenet/freenet_material/12.AtariLibrary/2.MiscellaneousTextFiles/showarticle.php?104 Anyway, I'll be very interested to see what he wrote here if a link is forthcoming. PS: no software which expects one size of RAM banking could possibly work with a different sized banking window unless the software expected that banking windows might be something other than 16K in size and were able to detect if this were the case. Claus writes that he revised his 32K window RAM expansion to use the 16K window scheme that Atari subsequently adopted. Apparently I mis-remembered his 32K banking scheme as an 8K one for some strange reason. My mistake. My nearly 50 year old memory must have mixed it up with some other knowledge of rom banking schemes or something. Quote Link to comment Share on other sites More sharing options...
ClausB Posted July 24, 2018 Share Posted July 24, 2018 There were 8 banks of 32K, so maybe that's why you remembered the number 8. Here's the old thread: http://www.atariage.com/forums/topic/122470-ram-upgrade-applications/page__view__findpost__p__1481893 The OP's photos show the correct chips for the 16 x 16K version but, as you noticed, no 256K DRAMs. 3 Quote Link to comment Share on other sites More sharing options...
ClausB Posted July 24, 2018 Share Posted July 24, 2018 (edited) Imagine the conversation: Jack! I put in your bloody board and it's munted as! Don't pack a sad. Gizza squizz... Aw, stink one! You didn't swap the RAM chips, eh? Not even ow! Bugger, I'm having a mare. Ta, cuz. Sweet as. Edited July 24, 2018 by ClausB Quote Link to comment Share on other sites More sharing options...
MEtalGuy66 Posted July 24, 2018 Share Posted July 24, 2018 DRAMs were expensive. Possibly he was waiting till he could afford them, or waiting to get the ballz to desolder 8 chips.. 1 Quote Link to comment Share on other sites More sharing options...
ivop Posted July 24, 2018 Share Posted July 24, 2018 I didn't know it either until Claus mentioned it himself in a thread somewhere either here or on Atari Sector. These 32K banked memory wouldn't be compatible with most of the 16K banked 130XE and Rambo/Wizztronics/etc. type memories though, right? So basically no extended memory software we have today would work, right? Right. If a new 32kB bank memory upgrade is ever made, it should use a different banking register and leave PORTB alone. If I'm not mistaken, Antonia already has two ways of banking, PORTB style and Axlon style ($CFFF). Another one could be added for 32kB-style banking (or even 48kB) Quote Link to comment Share on other sites More sharing options...
Gunstar Posted July 24, 2018 Share Posted July 24, 2018 There were 8 banks of 32K, so maybe that's why you remembered the number 8. Here's the old thread: http://www.atariage.com/forums/topic/122470-ram-upgrade-applications/page__view__findpost__p__1481893 The OP's photos show the correct chips for the 16 x 16K version but, as you noticed, no 256K DRAMs. You are probably right, and thanks for locating the old thread so I know I'm not totally losing my memory just yet! I knew it was a post you made in a thread I was remembering, and not some article. Quote Link to comment Share on other sites More sharing options...
ClausB Posted July 25, 2018 Share Posted July 25, 2018 Did most PAL XLs lack RAM sockets? Is that why the 320K piggyback upgrades were more popular in Europe? 1 Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted July 26, 2018 Share Posted July 26, 2018 Did most PAL XLs lack RAM sockets? Is that why the 320K piggyback upgrades were more popular in Europe? Hmm, IMHO after reams of PAL mainboards seen in the last 30 years... half-half. 50% of all 800XL mainboards have the RAMs in sockets, the other 50% not. Also I wouldn´t say that piggypack-updates are very common in Europe (ok, I can only talk about the german users). Most users prefer expansions for built-in, and there exists two wide spreaded solutions: The Compyshop 256 KB expansion and Klaus-Peters "mega-RAM" versions (3 major types with 256 or 1024 KByte). All of them incl. the Compyshop expansion need to remove one RAM chip and (Compyshop) one of the LS158 address mux chips and a PCB is plugged in. Then some wires must be connected. Because the access to US sources in the 80s was not easy, only a few nerds use sources from overseas. Some solutions here in germany (ABBUC Ram-Disk, Atari-Magazin Ram-Disk) based on your Quarter-MEG solution or similar US ones. And, Compyshop & Klaus-Peters delivers good instructions in local language for all XL/XE variants. So there was no really need for piggy-packing. All of these expansions also offers the ANTIC/CPU seperated access - a lot of users thinks in the 80s this feature is a "must have". Today we know a different story. Maybe the east-european market has different expierences... 1 Quote Link to comment Share on other sites More sharing options...
ClausB Posted July 27, 2018 Share Posted July 27, 2018 Ach, so. Thanks. Imagine the conversation: Jack! I put in your bloody board and it's munted as! Don't pack a sad. Gizza squizz... Aw, stink one! You didn't swap the RAM chips, eh? Not even ow! Bugger, I'm having a mare. Ta, cuz. Sweet as. anything.What? No love for Kiwispeak? Westies! Quote Link to comment Share on other sites More sharing options...
JR> Posted July 27, 2018 Share Posted July 27, 2018 Google translate didn't have a Kiwispeak option Quote Link to comment Share on other sites More sharing options...
ClausB Posted July 27, 2018 Share Posted July 27, 2018 https://www.absolutebus.co.nz/kiwi-slang https://anitahendrieka.com/56-typical-new-zealand-slang-words-use-like-kiwi/ Sources. Well, I had fun writing it anyway. 1 Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted July 28, 2018 Share Posted July 28, 2018 I support keeping our wonderful English language as distant as possible from the perversion of 'slang'. A common language is what holds a culture together. That is what we MUST have for our society to progress into the future. We must not let things such as 'ebonics' (as made notable by Slick Willie) creep into our culture! Learn to speak the language properly, or GET OUT! That's how I see it. If you don't speak properly, it only makes YOU appear to be uneducated. You degrade yourself by not speaking properly! . Quote Link to comment Share on other sites More sharing options...
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