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SuperSVGA

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Everything posted by SuperSVGA

  1. This one perhaps? https://macgui.com/downloads/?file_id=22127 It appears to match the screenshots in the document. I also have a small stuffit archive with a few versions, though I imagine one of them is the same as the file above.
  2. For something in production, you could try the TL2218-285PWR. I personally use the DS21S07AE (NOS) because I can find it for cheaper, but it requires a few extra capacitors.
  3. I've assembled a few but haven't been able to test, because unfortunately neither of my LC power supplies seem to work (even after recapping them) in either of my two LCs. I think the only other computers I have that take VRAM SIMMs are a Centris 610 and a Duo Dock, so I'll have to get one of those out if I can't get a power supply to work. One thing I noticed is it seems like there's a slight dimensional accuracy issue in the SOJ40 footprint, or it's just a mistake from the cheap PCB manufacturer I used. As you can see in this picture, it just barely doesn't line up right:
  4. The PCBs finally arrived, now if only the capacitors I had ordered before the PCBs had ever shipped... Oh well, I suppose they might be fine without the capacitors. So, what tests should I run on these besides just sticking them in and seeing if it goes?
  5. I actually had forgotten that the Portable doesn't have termination power. On the Macintosh Plus it's an easy fix, you can add a diode to an unpopulated spot on the logic board and it provides termination power, but I don't know if anything like that exists on the Portable. The only concern I see would be that power might go into other devices in the chain if they accept it, potentially drawing more power out than desired, but the draw from other devices might not be significant enough, I guess it really depends on what you hook up. SCSI spec says provided current on term power
  6. Here's what I threw together. Probably works, but feel free to make any corrections. Here's all the files: https://github.com/SuperSVGA/VRAM68/tree/main/VRAM SIMM TC524258BJ v1.0
  7. Which chips are you looking at getting? I can put together a quick design, and then you can modify it if needed. I've already got a few designs, but they tend to vary based on chip.
  8. Mouse input should be relative, not absolute. I believe the mouse typically provides X direction, X speed, Y direction, and Y speed as input. The Atari controller however provides each direction more like a button, so one for each of the four directions.
  9. MacTest definitely runs on the 68k, it goes back pretty far. Make sure you have the right version.
  10. I don't suppose you've tried starting up without loading TCP, selecting Restart from the Special menu, and then using TCP? You could also try running MacTest, I remember that having a few useful diagnostic tests.
  11. Here's one I found claiming to be from a Mystic Color Classic: https://www.worthpoint.com/worthopedia/512kb-68pin-70ns-vram-simm-selected-1806282637 They have two TC528257J-70, which should be 2Mb/256Kx8 70ns chips. Here's another http://web.ncf.ca/bj151/mac/mac-ram/68pin-512k-vram-simm.html This one is similar but with 80ns chips.
  12. I'm seeing some images online of 2 chip 512KB SIMMs claimed to be pulled from Macs, so it definitely sounds possible, but it's also possible not all models support them.
  13. Maybe for just a few, but PCBs are so cheap and let you skip the time it takes to remove the old chips and clean them up, plus it leaves more 256KB VRAM SIMMs in the world.
  14. There's still a decent selection of NOS Video DRAM chips around, so building your own probably wouldn't be too difficult.
  15. If the error is to be believed it's bit 18 of bank B. For future reference: Example: $AABBCCDD AA=8 bit mask for bits 31-24 BB=8 bit mask for bits 23-16 CC=8 bit mask for bits 15-8 DD=8 bit mask for bits 7-0 So with your code of 00040000 and with the masks expanded, it looks like this: 31 0 00000000 00000100 00000000 00000000 Maybe a scope or logic probe on the address lines might show you something? Here is the memory page of the schematic:
  16. Well the greater issue I see is that each client contacts another client, so everyone connecting needs to be reachable by everyone else. All the client’s would have to have a compatible networking setup, but possibly you might be able to get around this with an advanced relay to rewrite the packets and port forwarding on each client. Although NAT is part of the issue saying it’s just NAT doesn’t really get us to the right point. I’m guessing the important part is finding out how it interacts with Port Address Translation(PAT)/NAT Masquerade, and if Source NAT might be part of the solution.
  17. So I've done a bit of digging and found some of the answers, but also more questions... First of all, the main problem seems to be that Bolo was designed poorly to only work with computers directly connected to the internet (this was quite common in the earlier days of the internet), not behind a router or firewall. 4. Bolo.NetworkingFAQ Here's another snippet I found which probably explains why connections are problematic today. http://web.archive.org/web/20030620123025/http://www.lgm.com/bolo/guides/longfaq.html#netbolo I've
  18. Once I get home and on a 68k or PPC computer I'll take a crack at it. I found some source code digging around online, but I'll have to experiment with it to see if any of it is useful.
  19. Yeah it should be fine without the battery, although I've never tested what effect a low or bad battery has on the system. I would test with only Bank A populated if you haven't already, just to rule out any other problems. If swapping those out doesn't make any difference you might need to check traces between ram and multiplexers, possibly replacing the multiplexers (typically UI2,3,4,UJ2,3,4 IIRC). Of course I could be on the wrong track here, but that's just my guess. Now I'm having flashbacks to the SE/30 I had to hot glue all the ram in because the cli
  20. All the times I've encountered that it's usually something RAM related, but I suppose the causes could vary. http://bylenga.ddns.net/SE30 repair.html#SimasiMac Also, are those thin bright diagonal lines visible or is that just from the camera? I swear I've seen that somewhere before too.
  21. Mine just arrived, and I just finished assembling it. Looking good so far! Now I just need to bodge my circuits together so I can benchmark it against the 170MHz STM32
  22. It's likely the MacSnap Plus 2 for the Macintosh Plus.
  23. Are you still working on a design with just the bare STM32? I've made a few designs but so far they all cost more and require more assembly than just using a bluepill. I'm probably going to put some together anyway just for fun, and they definitely save on space.
  24. Booting from the ROM doesn't require the patch, so as long as you can access the main drive you can patch it from ROM, or any 7.1 or earlier boot disk I suppose.
  25. Well I bought a variable power supply and did some tests, and I wasn't able to figure out at what point it stops working. I set my power supply to 2v and unplugged the Macintosh Plus, and it drew around 2uA and retained its time and volume settings just fine.
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