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paulscottrobson

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paulscottrobson last won the day on October 5

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  1. Interesting. Could the X16 do Ant Attack , I wonder. (It could probably do anything if you scale the display up enough but then you might as well do it on a ZX81)
  2. Any vector game would be difficult ; any game with horizontally or vertically scrolling segments (say Frogger) would be interesting to code for. Anything which makes heavy use of the bitmap mode. Much of the speed benefit is lost because much of the data is 16 bit.
  3. I'm not convinced people are going to write enormous programs at all, let alone in assembler. Though it may be more useful in FORTH.
  4. They're very similar. In some ways the X8 is actually better. The shortfall in the X8 is RAM memory (and expandability, but that doesn't affect software so much). I'd say it was likely that a machine with the X8 level of specification would load code and graphics off Smartcard rather than holding it in SRAM, would probably not use much in the way of direct sound (though this is an X16 issue as well) and would be more likely to use 4 bit colour rather than 8 bit colour and/or have a lower resolution. It's backwards to the Plus4/16 issue really, they had identical hardware but much less program RAM. The X16 has more banked storage, but both systems have the same basic memory space.
  5. I would imagine they would have had a look at this to get views and ideas on the various platforms and possibilities, but I doubt we can significantly affect anything. Probably the most useful post is Bruce McF's ideas about having a serial extension if they do go round the X8 route.
  6. Lots. Whilst Block RAM is probably mandatory for VRAM, given that it's clocked at 8Mhz I would wonder if it would be better to use an external RAM chip.
  7. Nope, you could do it fine. It would be ridiculously expensive, very hard to design and require a large amount of board space, but it's *possible*. But even in the 1980s most computers had ULAs or custom chips, which are the forerunner of the FPGA. If you discount the 6845 CRTC chip as a specialised chip (like say the 6847 or 9918) then the Pet Apple Tandy Superboard group didn't have them. The ZX81 did but the design was buildable out of TTL, it was just making it cheap. Post Pet Apple Tandy ... the Spectrum was doable (as there currently exist TTL designs I think), the Jupiter Ace didn't have one, Microbee perhaps. There were some "Iron Curtain" computers ; Galaiksja that didn't, and some home builds (the latter two were originally home builds I think ?). But pretty much everything else had a ULA or Custom chip or sometimes more than one. I think the Ace is probably the most advanced non specialist chip design that wasn't published as a home build in something like ETI (but I'm probably wrong) but designed to be mass produced. No .... I think the Camputers Lynx was another non ULA design (256x224x8 colour), but it's still a bitmap design, drive a RAM chip with row and column counters at the right time and generated video from it. Not technically difficult, especially if you forbid VRAM access outside VBlank. I'm not sure if there exists a TTL design that does any graphics outside either a straight RAM to Bitmap or RAM to character generator design. It's just not economical and still isn't.
  8. I particularly like the ones where their computer gets remotely controlled and destroyed ....
  9. It's fine. You can have the fancy version with the keyboard and disk drive , or the functionally equivalent version by putting a Nexys A7 in a box which would cost a couple of hundred quid. Each to their own.
  10. "Don't know if anyone reads here *and* the forums but a chap posted this on there today : "you mentioned that you guys already have an X16 implementation based on FPGA - wouldn’t it make sense at this point to go for that?" and David responded with: "Not exactly. We had the X8, but decided it wasn't quite compatible enough. So I think Frank was going to work on the full X16 implementation." Has a decision been made I wonder ?
  11. That makes sense. I don't think it's a bad deal ; it's not the chips or the board that are expensive so much as the case, the disk drive (never understood this one !), the specialist keyboard. You could probably produce the same thing as a bare board PS/2 SDCard model for half that or even less. It's just a lot of money for me personally on something I mightn't use a great deal. Each to their own though.
  12. Your choice. Bit puzzled by the "3 FPGA" thing as the development system was a Nexys A7 and I think still is.
  13. It's reality. SID, PLA, VIC they don't make any more. There are still plenty out there, but they are diminishing and you don't want to pull them from other live C64s ; or if you do, you could have one "authentic" C64 and one with FPGA type chips. I think eventually it may become the case for all parts in a C64 that aren't standard 74 series logic. Stocks of 64k DRAMs won't last forever.
  14. It actually doesn't really work. It is the classic 6502 problem. If you use a VM it's compact but you get a 90% speed hit on that VM. If you use code, it's very long winded. Adding two 16 bit numbers in 6502 assembler is 19 bytes - three loads, three adds, three stores and CLC if you don't use zero page, which you really can't for general use variables. Interim solutions like JSR <add> .WORD v1 .WORD v2 don't work well either.
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