_The Doctor__ Posted February 27 Share Posted February 27 might help determine who is going to be designated leader of the chain gang and who is in what slot for usage and plumbing purposes as things evolve. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 27 Share Posted February 27 29 minutes ago, Geister said: Where are the existing schematics for the Z-80 cards? Also, could the connectors at the top of the Z-80 cards and the memory cards be used to provide local ram for the Z-80? Go to https://web.archive.org/ , enter atarimuseum, pick the first link, select a capture around 2020 or so, and drill down through the menus. The Z-80 schematics, and many others, are there. According to the schematics, the connectors at the top for the Z-80 card and 64k RAM card have the same pinouts. Since the z-80 card doesn't have RAM, it appears that the Z-80 would have used a 64k card in bank switched mode. My belief is that the Atari would periodically stop the Z-80 and check some I/O regions of memory to see what I/O there was to handle. I came to this conclusion based on my analysis of the Z-80 card and the fact that the Z-80 card does not have any I/O capabilities. I was going to do the Z-80 card then found out the card pictures and available schematic don't match. 1 Quote Link to comment Share on other sites More sharing options...
Geister Posted February 27 Share Posted February 27 Frustrating that more design docs were not preserved, but we probably have Jack Tramiel to thank for that. It looked like the Z-80 card was designed to work with the 80 column card and the memory card. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 27 Share Posted February 27 Still should be enough bread crumbs to follow to make a rendition happen, maybe not exact in every detail, but who knows, possibly something greater? Building from what is known to something even better is sometimes a good place to be. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 27 Share Posted February 27 16 minutes ago, _The Doctor__ said: Still should be enough bread crumbs to follow to make a rendition happen, maybe not exact in every detail, but who knows, possibly something greater? Building from what is known to something even better is sometimes a good place to be. Assuming you are referring to the Z80 board.... Let's just hypothetically suppose that a working Z80 board were to be created from grainy pictures downloaded from the internet archive of a website that doesn't exist. Who's going to port CP/M to it? Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 27 Share Posted February 27 (edited) If you were making like an ATR 8000, there's already a BIOS block for it. But if we are sticking with the z80 card only... Since BIOS is essentially the drivers for CP/M machines, whatever you stuff into the PBI handler space is a bit of the bridge as you stated the was no io ports on the card... This is not new though, since you are sort of using the 1090 as a back-plain, many z80 machines used the cards for each purpose. This means you can let the Atari be a card, share this of that/ or use cards for Multi I/O etc. I suppose softdrivers could be used for parts of the project. The whole Idea was CP/M can run on just about anything and one simply needed to provide a BIOS etc. Rather than trying to re invent the wheel on our part, we could follow something like this. http://cpuville.com/Code/CPM-on-a-new-computer.html A hard drive in the 1090 might be partitioned for both to use or a common area. CP/M commonly spoke to displays and such via serial, it was also capable enough to speak with video cards etc. It would be your choice as to the 80 col card, the Atari, Serial Term, or something else completely Edited February 27 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 27 Share Posted February 27 55 minutes ago, _The Doctor__ said: If you were making like an ATR 8000, there's already a BIOS block for it. But if we are sticking with the z80 card only... Since BIOS is essentially the drivers for CP/M machines, whatever you stuff into the PBI handler space is a bit of the bridge as you stated the was no io ports on the card... This is not new though, since you are sort of using the 1090 as a back-plain, many z80 machines used the cards for each purpose. This means you can let the Atari be a card, share this of that/ or use cards for Multi I/O etc. I suppose softdrivers could be used for parts of the project. The whole Idea was CP/M can run on just about anything and one simply needed to provide a BIOS etc. Rather than trying to re invent the wheel on our part, we could follow something like this. http://cpuville.com/Code/CPM-on-a-new-computer.html A hard drive in the 1090 might be partitioned for both to use or a common area. CP/M commonly spoke to displays and such via serial, it was also capable enough to speak with video cards etc. It would be your choice as to the 80 col card, the Atari, Serial Term, or something else completely Sounds like you know a lot about it. Are you volunteering? 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 27 Share Posted February 27 No time as yet. It's a crazy couple years. Quote Link to comment Share on other sites More sharing options...
Geister Posted February 28 Share Posted February 28 I'd like to take a run at it once I've helped my daughter and her husband with my new Grand-Daughter in May. Atari had a ROM for the Sweet pea Z-80 device (AKA 1066XL) that had the ability to produce 80 column and 40 column output with Atari characters. Hopefully some of that code would be a nice bread-crumb trail. I'm wondering if all the expansion boards for the 1090XL didn't come from breaking up parts of the 1066XL? Z-80 and 808X CPU's handle I/O very differently than 6502 CPUs. Maybe studying to code and the schematics of the 1066 and the 1090 will show a commonality that can be exploited. 1 2 Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 28 Share Posted February 28 (edited) <sigh> It looks like the Z-80 card, Atari had pictures of, wouldn't work anyhow. It appears the edge connector pads are reversed. Pads that should be on the front of the board are on the back and vice versa. For example, /EXTENB is connected to the heavy ground pad instead of ground to the ground pad. Address lines are on the wrong side of the board, etc. Either the board was tested with a backwards wired 1090XL or it was never tested. Maybe the boards were screwed up and used as props. I don't know. It's possible that if the edge connector pad connections are reversed that it will work. I have no idea. Edited February 28 by reifsnyderb 1 Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted February 28 Share Posted February 28 Which picture has it backwards? Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 28 Share Posted February 28 39 minutes ago, kheller2 said: Which picture has it backwards? These do. The easiest problem to see is pin 5. (Top picture, 3rd pin from the right.) That pin is /EXTENB, not GND. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 28 Share Posted February 28 Ok. The Z-80 backwards issue has been figured out. The traces are on the wrong sides of the board. lol 3 1 Quote Link to comment Share on other sites More sharing options...
DavidMil2 Posted February 28 Share Posted February 28 When I worked at Compaq, we had a board that was sent to us for testing three different times. Each time it came to us it looked different! Eventually the project was canceled, and we learned afterwords that nobody wanted to spend a lot of time on this board, so it got passed around from design team to design team. Each team made changes that were never properly documented. This looks and sounds like it might have happened to the 1090XL too. Things were changing so fast back then; I don't think that the bosses at Atari all knew what was going on across the company (especially with all the changes at the top). David 3 Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted February 29 Share Posted February 29 I got some prototype boards made. 🙂 5 Quote Link to comment Share on other sites More sharing options...
damanloox Posted March 1 Share Posted March 1 (edited) Has anybody tried 1090xl and 80 column card with U1MB? Any issues...? Also - any chance 80 column card can be... "modified" to install/use RGB instead of hdmi? Edited March 1 by damanloox Quote Link to comment Share on other sites More sharing options...
pancio Posted March 1 Share Posted March 1 (edited) Hi, My proposal for MIDI device on 1090XL. Schematic, PCB and gerber's files are available on my page. Have fun. Edited March 1 by pancio 8 2 Quote Link to comment Share on other sites More sharing options...
ndary Posted March 1 Share Posted March 1 just ordered one set for me 1 Quote Link to comment Share on other sites More sharing options...
pancio Posted March 1 Share Posted March 1 If you want to be The First Tester... 🙂 Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted March 1 Share Posted March 1 5 hours ago, damanloox said: Has anybody tried 1090xl and 80 column card with U1MB? Any issues...? Also - any chance 80 column card can be... "modified" to install/use RGB instead of hdmi? The 80 column card uses a Raspberry Pi Pico to drive the output. It should be able to be re-programmed to handle other output types. There are footprints already on the board for composite video but the program would need modified to handle the output. It probably could be re-programmed for RGB, however the board would have to be adapted. 1 Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted March 1 Share Posted March 1 On 2/27/2024 at 1:55 AM, reifsnyderb said: Oddly enough, Atari's picture of the 1090XL, and four cards, appear to show two 64k RAM cards that have different chips on them. This leaves me wondering if there was really a newer version of the 64k RAM card that would function as per the manual. The 64K cards look the same to my blurry eyes. The difference is one has a ceramic chip and axial vs radial caps. Although I do wonder why there is a VLSI chip on every one of those boards. I’ll see if I have any better pictures from actual samples. Quote Link to comment Share on other sites More sharing options...
scitari Posted March 2 Share Posted March 2 80 columns on the 1090XL remake. Thanks Brian! 4 1 Quote Link to comment Share on other sites More sharing options...
scitari Posted March 2 Share Posted March 2 17 hours ago, damanloox said: Has anybody tried 1090xl and 80 column card with U1MB? Any issues...? Also - any chance 80 column card can be... "modified" to install/use RGB instead of hdmi? I tried it and it did not work in my hands. 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted March 2 Share Posted March 2 u1m might be intruding into the 1090 pbi handler area, in theory all pbi equipment should be able to co exist if they identify and can be configured or can autoconfigure around each other. Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted March 2 Share Posted March 2 (edited) 10 minutes ago, _The Doctor__ said: u1m might be intruding into the 1090 pbi handler area, in theory all pbi equipment should be able to co exist if they identify and can be configured or can autoconfigure around each other. This is probably exactly what's happening. The 1090XL cards follow Atari's standards. Looking at the information, in my PBI document, I noticed these notes: ULTIMATE 1 MB $D100 - $D1BE I/O RAM (When enabled.) $D1BF Bank switch register $D1FF Emulated PBI device configuration $D600 - $D7FF I/O RAM (When enabled.) $D800 - $DFFF RAM or OS ROM (When enabled.) Edited March 2 by reifsnyderb 1 Quote Link to comment Share on other sites More sharing options...
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