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Scott Robison

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Everything posted by Scott Robison

  1. Interesting. It wouldn't be unusual for someone on a team who was working on an aspect of a project to assign copyright to the parent organization. I mean, Mark Zuckerberg probably isn't asked personally about all the copyright notices that are attached to Meta owned properties. Yes, it is a different situation, I just don't know if a copyright notice changes anything about the level of authority. But it is interesting.
  2. I suspect Christian though my evidence is circumstantial. perifractic.com and commanderx16.com are both registered through Public Domain Registry while the8bitguy.com is registered through GoDaddy.
  3. David's never been an active participant in this forum. I think it is safe to say that this forum was started by other team members. I'm glad this forum exists, but I don't think we can fault David for not making this his primary venue for sharing with the community.
  4. Considering how much I was able to get done with a 386 with VGA, including 320x200 256 color graphics, I could return to that if needed. For an imaginary machine that doesn't currently exist, I would like something like that but that built around a 32 bit descendant of the 6502. Not the 65832 that was proposed once upon a time, necessarily, but something that had a real 32 bit bus, not just 32 bit internal registers. In many ways ARM is that 32 bit (or 64 bit) descendant, even though I am not fluent in ARM assembly language.
  5. I can't point you to the exact source any longer, but David posted at one time on FB about the X8 that it wound up being too different from X16. The original thought had been that it would be really close, but the constraints on the FPGA (which originally only did video and a couple other "small" tasks with 128 K of RAM) were very severe when building a 65C02 CPU, other virtual support chips, and video and etc into the single FPGA. His original estimate of how long it would take to adapt X16 robots was way off base upon further reflection when more info came to light. Edit to add: The original thought was that X8 vs X16 would be a C64 vs a memory expanded C64 type of comparison. It wound up being more like VIC-20 to C64 (my words, not anyone else's). It would have been much more likely to fragment the ecosystem / community.
  6. I had a cousin who had one of the early Pong style (but not branded) video game systems. I was very jealous.
  7. Sorry to read that. Hope things go as well as possible. Merry Christmas!
  8. Here is the "final" release. Changed the thumbnail based on a recommendation from @SlithyMatt on discord, and I tweaked the audio to hopefully remove a hum I couldn't hear myself.
  9. I'm not 100% happy with it. Probably not even 90% happy with it. But I fear I never will be so I should just release it and move on to the next thing. At the moment it is unlisted. Since I don't have a fancy Patreon to get pre-release reviews from, I'm counting on you guys to tell me if it is particularly egregious in any way, and I'll publish it in a bit. {old link removed}
  10. He doesn't do most of the ports himself. He's very involved in the process, but other teams tackle the coding. Someone was working on the Apple IIgs, but they've gone radio silent last I'd heard. It's unknown when or if they'll get back to it.
  11. Clearly Perifractic made a significant contribution to the project, but he left a message when he withdrew with a list of reasons why he was leaving the project, and David followed up. I choose to accept them at their word as to the reasons why the parting of the ways came about, such as Perifractic's busy schedule, family issues, and so on. No one has said anything about them butting heads and thus the split, so I think supposition to that effect is not ideal.
  12. I think you have to ask the question "What is a demo?" We're accustomed to them being sound and video driven creations, but is that really *essential*?
  13. Raspberry Pi 400? I understand. I arguably shouldn't have splurged on the MEGA65. But I did, and I'm not sorry!
  14. We have them now ... sort of. Raspberry Pi.
  15. Note: I know I'm overthinking this. Bear with me. It's not quite that simple. Internally it can manipulate 16 bit quantities, but its external interface is still limited to single byte access. There are only 8 data lines, so if it wants to load a word from memory, it has to serialize that into two byte memory fetches. It's still a plus, but I don't know that one can say it is simply twice as fast. This is similar to how the 8088 worked vs an 8086. 8086 had a 16 bit external bus, so it would read 16 bits at one time. 8088 had to break those reads into two 8 bit reads. This is a big part of the reason as to why 6502 at 1 MHz could be competitive with 8088 at 4.77 MHz. Of course, 8088 had one advantage: lots more registers. It could do more math internally without having to go back and forth to RAM all the time. 65816 is not going to be able to use that as an advantage, though it has a much faster memory bus access cycle so it'll still be great. To get a better idea of how much faster 65816 is over 6502 at the same clock frequency, let's do a 16 bit add on each CPU. 6502: (26 cycles) CLC ; 2 cycles LDA addrL+0 ; 4 cycles ADC addrR+0 ; 4 cycles STA addrS+0 ; 4 cycles LDA addrL+1 ; 4 cycles ADC addrR+1 ; 4 cycles STA addrS+1 ; 4 cycles 65816: (17; assumes the CPU is already in the correct mode for 16 bit math) CLC ; 2 cycles LDA addrL ; 5 cycles ADC addrR ; 5 cycles STA addrS ; 5 cycles So 65816 is about 35% faster at the same clock rate. But of course Apple IIgs did not run at 1 MHz, it ran at 2.8 MHz. So really it is 77% faster than a typical 1 MHz 6502 machine. Well over twice as fast. For this example, anyway.
  16. I am not an expert, but in many ways it is difficult to quantify. The DE10-Nano includes an ARM CPU and supporting components that can be used to host an operating system such as Linux, plus the FPGA. Looking at just the FPGA part: Cyclone® V SE 5CSEBA6U23I7 (FPGA specs) 110K Logic Elements 6151K bits memory (768KB) Xilinx Artix A7 A200T 215K Logic Elements 13455K bits memory (1681KB) Based on that, it seems that it would be fair to say that the A200T in MEGA65 is twice as powerful as the FPGA in the DE10-Nano. Other aspects of the DE10-Nano are "better" such as the ARM cores built in. It's a lot like comparing CPUs. One can probably cherry pick some features to demonstrate that CPU A is better than CPU B, but other features might show the opposite to be true. Or comparing anything, really. The one thing I think it is safe to say is that the A200T can be used for more complicated designs that require more resources, but both FPGA are adequate for many tasks. It seems clear to me that MiSTer will not be able to implement the MEGA65.
  17. Agreed, but sometimes those imperfections need to be addressed publicly. Thank you though!
  18. I like this answer better than my own, I'm adopting it, except for the friend and high school teacher.
  19. I'm not sure this is something that I've ever given any thought to. I'm all but tone deaf so it has never really been important to me what type of sound a computer has as long as it has sound.
  20. I did say "or assemble". And even though the CPU doesn't have certain features used by most high level languages, that doesn't mean it can't be a benefit to write something in C, Pascal, or some other compiled vs interpreted BASIC. It all depends on what you're trying to accomplish. Or even compiled BASIC.
  21. It's funny, I want to do basically this with pi2iec, though over the IEC bus. A virtual device that can accept a saved file, automatically compile or assemble it, then you can run it. A little more typing but in essence the same thing.
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