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Everything posted by oracle_jedi

  1. 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.
  2. 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.
  3. 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!
  4. 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
  5. 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.
  6. 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?
  7. 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!
  8. 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.
  9. 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!
  10. Well the part nos appear to be different, so I am changing my assumption, to they are not interchangeable.
  11. Assuming the answer is yes, but figured one of you guys would know for sure.. The C64 BASIC ROM is interchangeable with the VIC? My 64 is booting up to a blank blue screen. Some cartridge images are working, but many games on the backbit/easyflash/ultimate ii carts have stopped working.
  12. As I expect you already know, the Amiga was designed by the same guy that designed the Atari 400/800 systems - Jay Miner - and like the 400/800, RAM is shared between the CPU and video display processor. Except that the video display processor - Agnus - can only see 1MB of RAM, so only the first 1MB of RAM is shared between the CPU and Agnus, and everything above 1MB is just for the CPU. Hence the first 1MB is called "Chip RAM", and everything beyond that is "Fast RAM" - because the CPU doesn't have to wait to access it on a cycle interleave with Agnus. Later Agnus chips upped the 1MB to 2MB, and some software titles will need that later revision, adding to the "why won't this software work on my Amiga!" challenge. The stock Amiga allows for easy expansion to 1MB RAM via the trap door, and you really need that 1MB because a 512K single drive Amiga was pretty useless - yes even in 1987. But beyond 1MB becomes more of a challenge. BITD there was side car options like the Supra mentioned earlier. Nowadays we have several easier options.
  13. An enthusiastic nod of agreement on the ACA500Plus option. It makes the A500 truly usable by adding 8MB of RAM and emulating hard disks through the CF cards, as well as the selectable WB options and much more. I got my first Amiga around 2017, and was really surprised how limited the basic A500 was. The WHDLoad system is powerful but even with 2MB of RAM I found many game files just would not load. I'd recommend you consider one of the case options for the ACA500Plus as the card is quite large and could be somewhat easily damaged.
  14. Yeah I know this is the ST/TT/Falcon forum, but this is also where the occasional Atari PC threads land. Does anyone have a definitive guide to the J2 and J8 headers in the PC1? A few years back Curt posted this information: But I am pretty sure this pinout is wrong. Bumzy developed an ISA expansion adapter some time back, but I don't recall him ever sharing a final schematic. He did share this image which came from Curt, and which shows most of the expansion: So from this, we can deduce that the pint out is in fact: So here is my question to the experts on the forum. One - does this look right to you? And two - do the J2/J8 headers need any kind of buffering, diodes, resistors or whatever before they are connected to an 8-bit ISA expansion card such as an XT-IDE or a Adlib Sound card? There are not many images of the actual PC1 ISA expansion adapter, but in this image there appears to be some resistors and a capacitor in the design, and I am concerned that I may damage the PC1 if I miss out a needed component.
  15. The XEGS is an okay choice. It will play Adventure 2 AFAIK, and most cartridge games for the Atari 8-bit line. It has composite video out as well as RF. But does not have SVideo as native. You will need to get a keyboard to play many of the more indepth games, such as Flight Simulator II or Rescue on Fractalus. If you want to explore the wider library which is very deep, you will also need a disk drive or virtual disk drive to load disk images. There are many SD card based options to choose from. You might also consider an Atari 65XE. It is the same as the XEGS but includes the keyboard built in, and also has SVideo output as native, but is otherwise the same. An even better option would be the 130XE. The same as the 65XE but with 128K RAM and more expansion options. A better choice all round. All XE systems have about the same build quality - about the same as the Jaguar, so somewhat brittle. The older 800XL is better made, but limited to 64K RAM (same as the XEGS/65XE). The 400 and 800 systems are the originals from 1979 . They are limited to 48K RAM and the 400 has only 16K RAM and a touch sensitive keyboard and RF only output. It is good for collectors but a poor choice for someone new to the platform. All systems can be expanded beyond the limitations listed here, including the 400, if you are handy with a soldering iron and willing to hunt down hand-to-find expansion options.
  16. I doubt he used any of these BASICs. He lists RM Nimbus as #1 but BBC BASIC as "awful". The BASIC shipped with the RM Nimbus was BBC BASIC. And as @carlsson pointed out, the VIC20 and C64 BASICs are identical. Half the list are variations on Microsoft BASIC/Extended BASIC yet are assigned completely random rankings. He's a troll. And not a very good one. Come back carmel andrews - all is forgiven!
  17. Maybe a picture of the board since you have the cartridge open. Do you have any other cartridges with socketed 27128 PROMs that you can swap in to check the board?
  18. I seem to recall Atari announcing all manner of exciting/interesting/wierd/dumb options and models back in 85. The 65XEP portable, the 65XEM 8-bit with AMY, the XF351 3.5 floppy drive, the 130ST computer and so on. A PBI-attached 80-col monitor would, in execution, have been an 80-col card on the PBI bus outputting a composite signal to a generic monitor rebranded as an Atari. I guess in the end they dropped the rebranded monitor, and dropped the PBI bus interface too but besides side-stepping the XL PBI does not match the XE PBI, that second decision seemed almost as dumb as releasing the XEP80 at all. It isn't clear what Atari hoped to achieve with the XEP80. They already knew they wanted to concentrate on the ST, and the XE and 2600 lines were simply a way to capitalize on their assets and raise needed cash. Perhaps they had already secured a stock of NS405 chips they didn't know what else to do with.
  19. What is it you are trying to do? Use a 220V Mega STe in the U.S.? The link is for a 220V PSU right? You would still need a step-up transformer, and then as PLM says, you'd have to hack the fan and power connectors yourself. Exxos sells a 110V unit that works, and avoids the need for the step up unit. I use one of those on my PC1. I would image Best Electronics probably sells an OEM 110V PSU for the Mega STe.
  20. Back when retro computers were just, well, computers, and there was a wide selection, and a constant release of new ones, few of which were compatible with anything other than themselves, the question of "which should I buy?" was a common theme in the letters sections of the publications of the day. The best advice I saw in response to this question was; find the software you want, buy the machine it runs on. I think that still applies today. If you want a large quantity of 8-bit quality arcade and RPG games, the C64 is the obvious choice. If you are more into programming or exploring esoteric apps, then maybe an Apple II or an Acorn BBC. If collecting cartridges if your thing, the Atari 8-bit, VIC20 and TI99/4A are all good choices. I would also suggest to our would-be retro hacker to start with machines that are still well supported by active groups, have a display output you can deal with, and have a relatively simple PC/Mac to target transfer system so that software downloaded from the web can be executed on the original hardware. Regional concerns also play a part here. The ZX Spectrum and Amstrad might be great choices for a European, but less so in the Americas. Likewise the TRS80 CoCo and TI were huge here, but fared less well in Europe. MSX did well in Asia Pacific etc.
  21. Isn't the other problem with this picture that the Apple II isn't actually turned on? The system saver fan is on, but the II's power light looks to be dark.
  22. Well I was thinking more of productivity apps - Word Processors, Spreadsheets and such, but you raise a good question. On the Apple //e, were there many games that used 128KB, or were they still targeting a wider audience with 48KB games?
  23. Apple seemed to get a lot of things right with the II+ and then the //e. I didn't know all the 80 col cards worked to the same standards but that's cool and makes so much more sense for developers and consumers. I liked how Apple made 128KB RAM and 80-columns an effective standard with the //e, it was a single upgrade card from Apple if I remember. I think its the direction Atari should have gone with their aborted 1400XL. 80 cols and 128KB RAM in 1983 would have made so much more sense than built in 300-baud modem and a speech synthesis unit.
  24. Oddly, my memory was that Bug-Byte published some of the worst commercial VIC20 games. Maybe slightly better than Liversoft, but only just. Am I remembering this wrong?
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