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TomXP411

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TomXP411 last won the day on October 4

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  1. We've already talked about the ROM in other threads. Short version, there's no need to license Commodore's ROM. There are several 6502 BASICs out there, and there's more than enough brains in this community to crowdsource a kernel - even without relying on something like the open KERNAL started by the MEGA 65 crowd.
  2. There are several ways to launch a suborbital spacecraft that don't use as much energy and fuel, but they require more infrastructure than anyone is willing to invest in right now. I'm sure we can also eventually do a better job with liquid hyrdogen fuel - which can be made 100% carbon neutral. And that doesn't even get into the possibilities for efficiency improvements, like what we've seen with automobiles. Cars today use maybe 1/4 of the fuel of cars made in the 40s and 50s. Part of that is engine design, but a big part is also due to the design of the cars themselves. Fuel economy closely related to mass, and so making lighter cars makes for more efficient cars. With spacecraft, the same is true. Something 90% of a spacecraft's mass is fuel, and much of that fuel is spent lifting other fuel. So 1 pound of reduced orbiter mass means 10lbs less fuel is used. So materials design plays a big factor. Likewise, making engines more efficient can massively reduce the fuel cost. If we can improve engine performance by 25%, that might eliminate half of the fuel needed for launch, just due to the exponential nature of the fuel equation.
  3. Yes, it went up back in August. The name was wrong, though, so it was the "AS500." At the time, I was thinking, I didn't know IBM had released a follow-up to their popular AS400 mainframe..
  4. You can always grab a D64 of the game and run it in your choice of modes. The TheC64 is capable of running in NTSC or PAL speed, regardless of the HDMI frame rate you're running. I don't remember the exact process, but you can use filename shortcuts or generate a configuration file for your game.
  5. Yes, there would be no reason the FPGA version can't be upgraded down the road. It would also be possible to run this on other multi-system FPGA computers. There are several popular ones out there, including MiST, MiSTer, and Turbo Chameleon, I believe the ZX Next and MEGA 65 hardware will also be able to load alternate cores, so it's possible that the Commander X16 could be widely distributed as a software core, in addition to being hardware only. I'd happily contribute to a Patreon to develop FPGA cores for these systems, especially if the chip shortage is going to make it difficult or impossible to get the kit version out in 2022.
  6. If I recall, the system clock is also driven by VERA. In that case, there would be firmware changes needed for VERA to live on an 8080 style system. Either VERA would need to generate the clock, or you'd have to drive the I/O side independently from the GPU side of the core. In either event, you might as well modify the bus sequencing to account for 8080 style I/O while you're at it.
  7. I think the same thing. More than that would mean a lesson in 65x logic design, which could be a thread all of its own.
  8. That's amazing. I'm amazed at what people keep coming up with in the 8-bit space.
  9. Thanks. That gives me a place to start.
  10. I know this has been answered somewhere else, but the information has been buried beneath a mountain of other comments. @Frank van den Hoef Can you talk about the FPGA that's actually being used for VERA? All this talk about FPGAs and what can and can't be done has got me itching to know more - and possibly to do a deep dive into the technology, myself.
  11. To think... there was a time when William Shatner was doing Star Trek conventions just to earn a living. And now he's got the cachet to make a trip to space. It just goes to show how anyone's fortunes can change, with the right circumstances.
  12. See, this is not quite correct...an FPGA can do none of these things by itself. If you simply feed power to an FPGA, it will sit there. It requires programming and peripherals to perform even a simple operation. It's most appropriate to say that an FPGA is part of a computer, just like the Broadcom BCM2837B0 is part of a computer. Context and programming matter, and we don't think of cash registers, arcade games, or air conditioning thermostats as computers - even though they may contain a microprocessor and perform fairly complex tasks. Clearly a smart thermostat has all of the requisite properties, but we're never going to confuse a Nest thermostat with a desktop PC. Context matters, and while a complex FPGA can be one component of a computer, it's not "a computer" any more than the Broadcom SOC. It's just one piece of a system that may or may not itself be a general purpose computer.
  13. Yeah, I can't stand Tapatalk and don't want the prompt every time I visit. I woudn't mind a one-time prompt, but every time? No thanks.
  14. You're not compiling assembly code. You're assembling it. Compilers and assemblers are different things. Anyway, the !BYTE, !PET, and !SCR are assembler directives for raw data. You're correct that the DB directive is the replacement on other assemblers (including other 6502 assemblers.) The thing to remember is that non-Commodore computers don't have PETSCII, and everything else you're likely to encounter uses ASCII. (There were some non-ASCII mainframes, such as IBM EBCDIC, but we're not going to talk about that.) So the !SCR and !PET commands are there to convert ASCII text to the PETSCII or the screen code equivalent. Since an "A" is 65 in ASCII, 96 in upper/lower case PETSCII, and 1 in screen code PETSCII, you have to tell the assembler which code to use for "A". But the Spectrum only talks ASCII, so you don't need to re-encode text. This means you don't have or need any of the cross-platform encoding directives like !PET. Just use the DB directive to encode the ASCII values to binary, or check your assembler manual to see what it uses for text encoding. Since every assembler is a little different, you definitely need to read the manual. And yes - there are equivalents to CPX and CPY: all the various "ld" instructions, such as LD A,B or LD B,C. The equivalent to indexed instructions is anything using (HL), so something like LD (HL), A copies data from the Accumulator to the address pointed to by the HL register pair. There are also no indirect operations, so nothing like LDA ($20). Instead, you have to LD HL,20h and then LD A,(HL). You'll find that the Z80 has a different way of doing things, and it's actually easier to code for in the long run... the problem is that in the short run, you want to do things like zero page addressing or indexed indirect addressing and can't... but once you translate the concepts to Intel's simpler paradigm, it's actually easier. You have 7 registers to work with, and 16 bit math only takes one instruction. So a lot of things we need to do the hard way just take one operation on Z80.
  15. It’s really not quite the same. David did a review of the TheC64 where he shows the audio and video lag of using software emulators. It’s one reason I prefer my Ultimate 64 or my MiSTer over VICE when playing Commodore games. And that’s aside from the fact that a small ARM SOC just can’t run the Commander emulation at full speed. It struggles to do 4MHz on a Raspberry Pi 4, and that’s more powerful than most of these little ARM SOCs.
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