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About oracle_jedi

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  • Birthday 01/06/1971

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    Nothing to Declare
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    Seattle, WA
  • Interests
    Atari 8bit, 7800, Jaguar, ST, PC1, Falcon; Commodore VIC-20, Max, C64; Amiga 500, 1200; TI-99/4A; Sord M5; Camputers Lynx
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    Lemmings (Atari PC1 in glorious CGA)

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  1. @eightbit has confirmed the user-port reset button allows the Atarisoft titles (Pole Position, Ms. Pac-Man, Moon Patrol) to start. I can confirm the RAM expansion reset-hack allows the same titles to start. That leaves several possibilities: The software files bluejay is loading are corrupt. They will never work. Bluejay's hardware design is wrong. It works on a real Commodore RAM expansion but not his. Bluejay's VIC20 is in someway different from the ones eightbit and I are using. Later VICs could not play Jelly Monsters due to initialization differences with earlier models. The RAM chip bluejay used is losing its contents upon reset. Some newer static RAM chips have an auto-power-down mode whereupon if the CE line goes low, it basically turns itself off, losing the contents. Load up any Commodore cartridge image and press the reset button. The game should start. Which ones? Pole Position, Ms. Pac-Man and Moon Patrol can be started with the reset button eightbit detailed.
  2. Yes, it was grounding the RESET pin. The original VIC20 RAM expansion carts used HM6116P static RAM chips, so as long as they got power, the contents were not lost.
  3. Like I said. There is a RAM cart mod that performs a non destructive reset, allowing the Atarisoft titles to start. Yes INCLUDING Pole Position.
  4. Which games? Because Pole Position is not one of them.
  5. There's a mod you can do on the RAM expansion to add a reset switch that does not wipe RAM. I don't know if this differs from the user-port reset switch mod. I think they are the same. Resetting the computer does not wipe memory unless you power cycle it. I modded a 16K board with a reset switch and also to sit in BLK3 and BLK5. I used to use it to play cartridge dumps before I got a Mega Cart. As @carlsson stated, there are not many carts that need it this switch. They were mostly Atarisoft titles. Probably your best option today is buy one of @brain UltiMEM carts, but if you're not enjoying what you're finding you might be better off just concentrating on what you do enjoy.
  6. I did an internship at IBM in 1989/90, back when Big Blue was still big and mainly into HW. I used the phrase "assembly language" at the lunch table one day, and they all jumped on me. "It's not assembly language! It's ASSEMBLER!" Sure enough, at that time, every IBM-branded manual I could find labelled it ASSEMBLER. You wrote Assembler, and assembled into machine code with an assembler.
  7. Hmm, okay. The PVM has RGB/Sync through four BNC jacks. And the monitor will report "NO SYNC" if it doesn't find a sync source, which isn't the case here. I think I may try replacing the patch lines from the RGBS pads on the board and see if that helps. I don't know if this is relevant but the PAL Sord units have a pretty dreadful composite video quality at the best of times with a lot of noise in the image. I can only assume the RF output hid a lot of that. I have two PAL Sord units and they both exhibit the same behavior. Thanks again for the insights.
  8. I swapped the board for a second one, resoldered everything, and switched to a second cable. This is the output on a Sony PVM 14N6U. Something is seriously messed up with the way the Sord does things.
  9. Roger that. I'll try to check all the connections again this weekend and hope it makes it look better. Otherwise I may have to try to add in the mod @ChildOfCv suggested, which looks challenging!
  10. Okay, but the monitor does work with RGB/CSync inputs from my Camputers Lynx and Acorn Electron, and even the Amiga which did not use the HSYNC/VSYNC option on this display. What does "go through a buffer' look like in terms of components? Is that an easy mod? Thanks
  11. It's this one: 319650 - Luma/Chroma in separate RCA connectors, or analog OR digital RGBI with separate sync in a DE9 connector, with a switch to decide on digital or analog The monitor has a DE9 for the RGB and a switch on the back to select between RGB or RGBI. There are also RCA jacks for Chroma/Luma, and another switch to use just Chroma as Composite. I just tried using RGBI mode but that looks even worse.
  12. Seems a real shame that so many games released back in the 80s/90s didn't better exploit the Amiga's abilities. From what I have seen, I would even go so far as to say most games of the era looked pretty much identical on the Amiga and the ST. Thankfully they sounded so much better on the Amiga. I moved from the 400/800 machines to an ST, and was disappointed that the 16-bit machine was so bad at arcade games where scrolling was used. Having been spoilt by the silky smooth scrolling of Dropzone, Ballblazer, Elektraglide and so many others, the jerky scrolling of ST games seemed like a step backwards. A clear case in point was R-Type. On the ST version the scrolling was terrible. I expected the Amiga version would be smooth, knowing what the hardware can do, but in my opinion, the game looks no better than the ST version. My Amigas havn't been used recently. Just been busy with my weird 8-bits (Sord M5, Camputers Lynx), but I am going to have check out Pacmania when I get them powered up next. Any other games you guys would recommend as a showcase of what I know the Amiga can really do?
  13. Hoping to get some educated opinions on how to fix the display from a Sord M5. I have both a PAL and NTSC unit. The PAL unit uses a TMS 9929A VDP. I installed the TMS-RGB adapter on the underside. But the display from my Commodore 1084 is pretty awful. The display is compressed at the top, and the left hand side of the display is underscanned, so some of the text is missing. The colors are also off as this is supposed to be green, but I figured I'd worry about that later. This the same unit using composite output (the monitor is NTSC/RGB so I lose the colors). And this is what we are supposed to see (NTSC unit output via Composite Video) I figured the CSYNC wasn't working, so I tried both the TTL and even just feeding the whole composite signal to the CSYNC line, which corrected the underscan, but did not improve the top of the picture where everything is compressed and unreadable. The Sord M5 is similar to an MSX or Colecovision as in that it uses a Z80 coupled to either a TMS9918A (NTSC) or TMS9929A (PAL). I've seen the install guide at tms-rgb which suggests removing the L9 Inductor, but I don't know if the Sord has this, and this is a PAL unit anyway. Hoping someone might have some suggestions on how what is causing the garbled display. Is it the CSYNC or something else? Any pointers on things to try?/ Thanks!
  14. Really isn't complicated at all. Since you want to keep your current floppy drive, you're just plugging the Gotek in the floppy disk connector on the back of the Amiga as you would any other second floppy. The switch @NumbThumb linked you just allows you to then use the Gotek as your primary boot drive instead of the internal floppy. It's not required, but without out it, you would have to boot up of a real floppy and only use the Gotek as DF1. Most commercial games need to be booted off DF0 so obviously that would present a problem. The switch adapter installs into a socketed IC. No soldering required. Its relatively easy to carefully remove it, install the adapter, and then insert the chip you just removed into the adapter itself. Route the cable out the back of the Amiga and you are done. If you prefer, you can drill a small hole on the back of the machine to mount the switch. Now you can boot off the Gotek. There's a really handy menu disk that you can use to select which disk images you want to load, then you press F10, and the Amiga reboots and loads whatever you selected. Alternatively you can use the buttons on the Gotek itself to step through the list of ADF images, although once you have downloaded a bunch, that gets tedious. This is probably the easiest way to run Amiga software you download off the internet.
  15. Good question on the PLA. So I found this web site: https://www.vintagecomputer.net/commodore/64/commodore_64/index.cfm And dropped the diagnostic image onto the Backbit cart: Wow, looks like all kinds of problems!
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