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Kalvan

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  1. If you don't consider that most home computers back then didn't have FPUs (making the the sole Floating Point data variable type a hair-tearing bug rather than a feature), the biggest problem of BASIC was that it was purely sequential, aside from specific jump commands. Using commonly accepted programing conventions inherited ForTran and COBOL, if you needed to patch in more than ten lines between any two existing acceptable lines, you had to rewrite the subroutine completely from scratch, and God help you if the result then impinged on the line space of the subsequent subroutine, resulting in cascading rewrites and even more hair tearing. There's a reason the programming world has moved on to procedural programming paradigms, and further developments from there. Personally, I would prefer the development of a 21st century version of LOGO.
  2. VERA would still need a second DMA (otherwise you get bus contention issues with its internal VRAM) and much more than 32 bits of interface with System RAM to make this work. Hindsight on matters like these is always 20/20.
  3. I think what RJE is hoping for is something like separate pins for video data meant to go directly to VERA, while main CPU data goes to the 65C02. That's how most game consoles handled their pinouts (or at least the only systems made in the cartridge era that I have data for that didn't handle it this way were the Atari 5200 and Commodore 64 Game System, which were based on 8-bit home computer architectures). There were also several computer designs that worked this way too, most especially the TI 99/4 and MSX machines (or at least cartridge slots 1 and 2 on the latter). The problem is that this isn't how the SD card system seems to work. To make it work like that wouldn't necessarily require much addition to the FPGA softcore, but it would definitely need tracing the SD card interface for specific I/O pin lanes (and if the system only has one I/O line, or even only one input and one Output, forget about it), a complete revamp of the SD card firmware requiring two physically different file systems, a near complete rewrite of Kernal and the back end of much of the rest of the ROM, and a significant rewiring of the motherboard and the VERA daughterboard. And, when you consider that the Geometry Synthesis and PCM channels are completely physically separate from YM2151, and aren't even accessed from the same memory banks, things get even messier...
  4. They would have needed to have started ca. 1982. Have them contact Fujitsu and see if they can work together on the follow-up to the FM-8/7 as the CoCo 3. Possibly contact Hitachi and together from a SIG based around the 6309 and H8 series, so that both companies could have had better CPUs for cheaper than the gouge Motorola was demanding for the 6809. The FM-77 in a keyboard-console form factor could have been the CoCo3, and the the FM-77 A/V could have been an ATL CoCo4. Then, when the FM Towns is coming out, market a version of that in America, but minus the kanji ROM, and with cut down entry-level versions that omit the CD-ROM drive, but keep the DeskMate GUI. Call it the Tandy 5000/10,000.* *replace the Yamaha YM2612 with the WM3812, to provide compatibility with SoundBlater and AdLib functionality, and the Ricoh RF5c68 with the Ensoniq DOC II, OTIS, or OTTO, along with the existing Texas Instruments SN76496 clone.
  5. Well, assuming things like drivers, sound font data, and isolation componentry are non-issues, and no fair using anachronistic or custom silicon... For a late eighties version, It would feature the following: Geometry Synthesis Component: Either a QuadPOKEY or x2 Phillips SAA1099 FM Synthesis Component: Yamaha YM2151 OPM, Yamaha YM2164 OPP, or (Especially) YM2414 OPZ and YM3012 DAC Wavetable/PCM Synthesis Component: Seta X1-010. It features twice the max sample rate of PAULA, and double the channel count of the SPC 700, at the expense of 8-bit sample width, and a 4 bit master volume registers, and was used by multiple arcade manufacturers. The Namco C216, SegaPCM, and various chips by Konami were used strictly in-house by their respective makers. Sound CPU: Hudson HU6280: Between its mass move instructions, three data busses (one of them full-duplex), extra general-purpose register (Z, which can be pressed into service as a Master master volume register), six extra wavetable sound channels, and compact surface-mount package.
  6. Read about it here. For someone looking to port Wolfenstein 3D, Doom, or Marathon (Duke Nukem 3D or Quake may still be bridges too fat) or create an original first-person 3D concept for the Commander X-16, this might be worth looking into, considering that it appears to have been made to run on the Apple II, Atari 800, BBC Micro, and Commodore 64. Considering that the X-16 runs at four to eight times the clock speed. Then again, I haven't taken the time to calculate the average percentage CPU overhead involved in bankswitching the High RAM for this sort of thing. I also don't know whether or not it makes use of the undocumented/illegal opcodes...
  7. My family's first computer was a TI 99/4A, followed by a Coleco ADAM and then a Zenith Data Systems PC clone. The first computer I personally owned was a machine by a company known as Orange Logic. it used a PIC microcontroller as a CPU, and the sound system consisted of an RCA 1802 and an 8-bit DAC, and the built in language was Chip-8.
  8. Xanthrou, your design feels like the the chipset revision the FM Towns Fresh/II/FMV Towns should have been but sadly wasn't. It also works as high-end (for the time) arcade hardware turned into a professional workstation, much like my Eighties concept. That said, for the sound CPU I would have used a Zilog Z280 at double the clock speed, so that the sound chips could reach closer to their potential relative to the rest of the chipset. As for my ideal Nineties computer, well, it would probably be a further evolution of my proposed Eighties computer featuring a MIPS R4200 or better. Realizing that would probably demand at least an FPGA Arcade Replay Board 2 for prototyping...
  9. A little, but even more various electronics channels on YouTube. Personally, I was more partial to Micro Men, Silicon Valley, and Computer Geeks.
  10. I realize this may sound like a really dumb idea, but... How about, when the time comes to engineer the Commander X16c, the team simply doubles the motherboard layer count, puts chips on both sides of the PCB, and, on the side facing up, use PC Card slots with some customized pinout for expansion? It should permit more hard silicon and ASICS from its big brother onboard, and thus be more hackable for those who prefer it that way while still being a better fit in a keyboard-console or even laptop form factor. Or maybe I'm totally off base.
  11. David Murray's Commander X16 is a perfect slice of computing counterfactual, the higher performance followup to the Commodore 64 the 128 should have been but sadly really wasn't. The only things it would have been missing would have been if VERA had been fully backward compatible with VIC II and SID code and modes, and the Yamaha YM2151 was replaced by a YM3562, YM2412, or YM2203, since in OTL Yamaha refused to allow Tramiel to put the OPM in the Atari ST for love or money! But this is not what this thread is about. We have a vast majority of fora on this site for this excellent piece of 8-bit computer engineering, and once it comes on sale, I plan to buy one, a VGA monitor, a pair of new Super Nintendo compatible game pads, some sort of LOGO, LISP, or Action interpreter/compiler, some sort of mouse (will the SNES mouse work with GEOS, or are we stuck with a PS/2 mouse?) and give the whole shooting match to my nephew for his 11th birthday. No, this thread is for those who wish to share their visions for the sort of computer plausibly from that era that they would have wished were produced, using, if possible, the same limitations that were imposed on the development of the Commander X16. Specifically, that whenever possible, currently available hard silicon is used for the final product, and FPGAs are kept to a strict minimum. Because I'm starting this thread, I'll go first. I wish to turn the graphics concepts from the Atari Advanced Engineering Division and Atari Semiconductor Group into a tangible computing product. Specifically, I would like to create a hypothetical ca-1987-1992 hardware revision with roughly 32 SILVER Object Generators (from the Rainbow Chipset) and 192 PENNY Sprite engines(from the Omni Chipset), using the HEATHER Display Adapter and VIVIAN Video MMU/DMA. For the CPU, I plan to use a Microchip Technologies PIC32 (The MIPS R2000 was introduced in 1985, featuring roughly half the transistor count of the Motorola 68020 and Intel 80386 while breaking no new ground in transistor, gate, or switch design. It was only expensive because it was rare.) clocked at an arbitrarily low speed. I choose this chip because, while the Atari Advanced Engineering made every attempt to make the design CPU agnostic, it was quite clear that a 65xx architecture chip simply lacks the necessary register count to make efficient use of these chips. The reason I'm not going with a Motorola 680X0 or 6809 derivative is that Freescale has ceased production of the 68000-based Coldfire and Dragonball microcontrollers, and Renaisis will only sell H8 series chips to existing legacy customers, insisting that new customers buy into their Super H and ARM-based lines. For the sound stack, I plan to use either a 65816 or a 65C265 microcontroller as a sound CPU, and for actual sound chips a QuadPOKEY (POKEYMax, with an ASIC version in the final production version), AMY, a Yamaha YM2414, and a Seta X1-010 Essentially, this is the spec I would like to have: CPU: MIPS R3000+MIPS R3010 FPU, 21 MHz, Optional 30 MHz version System RAM: 1.5 MB, Expandable to 8 MB, or up to 2 GB via expansion cards GPU: HEATHER II (Display Controller/Video Data Selector) + VIVIAN (Video MMU/DMA) + x2 QUARTER (32 SILVER Object generators and 192 PENNY Sprite engines total) Capable of displaying a maximum of 65,536 Colors on screen AT 640X480 out of a master palette of 715,264, With a maximum resolution of 960x720 (256 colors). Optional Texas Instruments TMS32010 DSP+TMS32015 Video FPU VideoRAM: 1.5 MB, Expandable to 8 MB, or by video card Sound CPU: Western Design Center 65816 or 65C265 Sound Chip: QuadPOKEY, Yamaha YM2414 (FM Synthesis Chip, 8 channels, 4 operators each, eight possible waveforms)+YM3014 DAC, AMY II (Sixteen Channels Additive Synthesis, Eight Operators Each), Seta X1-010 O.S. BSD Kernel Based, C and BASH Shells, SNOW GUI I'm willing to compromise on the GUI. Something more like Awesome, DWM, or Xnomad might work better. And I don't know whether to adopt HEATHER's color encoding scheme (it's based off of the NTSC colorburst cycle) or stick with an RGB or Magenta-Yellow-Cyan method. The biggest question is whether or not all of this would fit in a DE Nano for prototyping, or whether I should wait for an FPGAArcade Replay Board2?
  12. Well, from what I've seen of motherboard prototypes on YouTube videos, VERA and the YM2151-YM3012 combo (and the SAA 1099s that are about to go bye bye) are on opposite sides of the current motherboard design. Any circuitry solution that corrals all the sound signals to and from the expansion ports and/or an external output jack will need its own circuit layer all to itself.
  13. I'll have to describe my personal dream computer in the general retro-computing forum but I hope that it isn't too much of a hijack to post a few comments to second guess Mr. Murray's chip selection a bit. Personally, the way Mr. Murray and his team, in terms of remaining true to the vision and ideals they have set themselves up for the Commander X16, have done as perfect a job as could be expected without commissioning masks for VERA (and separating it from the Geometry Synthesis/PCM sound engine) with Samsung, TSMC, or Global Foundries, or gone to some FPGA to ASIC pathway specialist. Still, I would have chosen as my CPU either the Hudson Hu6280 or the Nintendo SA-1, assuming I could find some means of assuring a steady supply that did not involve cannibalizing them from classic consoles and game cartridges. I know, they're surface-mount chips, and IBM's patent on it didn't expire until 1987, not to mention the hassle integrating them on a mostly DIP socket motherboard, but you get demultiplexed address and data pins and full 16-bit data busses, with no need for external bank switching. In fact, you get three, at least one of them full-duplex if my interpretations of the pinouts are accurate, not to mention the Hu6280's six wavetable sound channels and mass-move instructions or the SA-1's two extra registers and hardware multiply and divide instructions in 16-bit mode. I would have also possibly added in a Super Nintendo cartridge add-in DSP or two (Their cores date to 1982), with the cover story being that this computer is released in 1987-88, with Hi-Toro Labs having been bought out by someone else, as competition for the Amiga, Sharp X68000, Acorn Archimedes, MSX 3/Turbo R machines, and VGA and Ad-Lib/Sound Blaster era PC Clones. But that's just me. Personally, in Mr. Murray's shoes, and without his example, my first effort at this sort of thing would have been much kludgier.
  14. I have a question that needs answering: Is there a specific, dedicated audio buffer, and if so, is it part of VERA's VideoRAM, or is it part of System High RAM?
  15. I have a wild, wacky suggestion. While I do approve whole heartedly of the porting of classic arcade, console, and computer franchises like Gradius, R-Type, Bubble Bobble, Mule, and early SCUMM Engine LucasArts games, why not also have someone contact the likes of Starsoft, Yacht Club Games, and Humble Games to port modern retro "Pixel Art" games, like Shovel Knight, The Messenger (2018), Cyber Shadow, Savior, Axion Verge and the like? I am trying to imagine The Messenger with SID-like PSG sound exclusively for the Past and PCM and YM2151 audio added for the Future!.
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