Posts by LGB-Z

@Truss: I don't know, but Commodore 65 is intended to be C64 compatible at some degree at least ... So about the Mega65, if it wants to carry the original concept of C65 further, should not forget about the roots. However that's true: even the original C65 was not meant to be a 100% compatible C64 in C64 mode (well, just the CPU is not the very same - think about illegal opcodes -, and so on), that's the other point. And I think, C65GS/Mega65 has already a great work to even lighten this limitations of the original design (for example: think about the incompatibility caused by the different behaviour of read-modify-write opcodes of 65CE02 core, which is already solved - if I know well - for Mega65).

But I agree, that only "an FPGA C64" it wouldn't be as interesting as Mega65 is, there are projects already like that. C65 is an interesting (however it was way so late to be developed by Commodore, IMHO) machine, and with the original concept, and a proper case/keyboard/etc it really feels as a brand new (and quite modern) 8 bit machine, which is a great feeling! It's just another - though very important! - point, that Mega65 has even more developments over the C65 features, for me, this makes it even more interesting and a "must have" item Personally, I felt something similar with C64DTV, that I have something which "looks like" a 8 bit stuff (and not only a software emulation), which carries the original concepts further, and "just can be bought" and ready to be discovered, etc. Mega65 is even better with a proper case, and the general feeling about being a "real computer", which is not so much the case of C64DTV (well, it's just a "joystick", you have to hack it, etc).

But for sure this was *ONLY* my personal view, nothing more.

By the way, what is not clear from me (even that document is confusing - for me, at least): where are the sprite pointers in bitplane mode, and what kind of memory is used to fetch sprite data then according to the sprite pointers? I guessed it's maybe bitplane 2 area (as it seems to be the one which is used with "classic" sprite features, ie collision, sprite-background priority, etc). However document states that sprite pointers are always at the high end of the video matrix .... Ok (natural stuff in case of VIC2 notion), just with bitplane mode you don't have classic video matrix too much, also the bitplane itself can be 8K or 16K (H640 bit) as well, so it's kinda unclear. Or maybe it is only for me

http://www.devili.iki.fi/Compu…_Specification/page6.html

See from section 2.4. However I am not sure if it gives more information.

What I could found for example, it contains some of the VIC-III information as well. VIC-IV indeed is a further-extension of VIC-III (which was the original chip in C65,CSG 4567, according to the documentation, as you've quoted too) for c65gs/mega65.

Maybe it's a silly question, but: I thought originally that the original nexys board will be used, connected to another board. Is it the plan? Or a really own board also replacing the devel FPGA board, and the FPGA etc themselves will be soldered on the very own and unique board of the Mega65?

Hmm, having Z80 support directly in FPGA would be cool (also for C128 mode, hehe) but it requires FPGA resource then for that ... Anyway if Z80 is implemented, and also have the "hypervisor traps" etc, then it also makes possible to "emulate" other Z80 based computers as well. However, I think it's a bit out of scope of Mega65. Maybe for the C128, it's still somewhat understandable to include, but I hardly believe that it will be included anyway ... It's even interesting to think about on the 65xx line: if "emulation" using "I/O trap" anything makes that possible, other Commodore machines can be "emulated" like C+4 But that's at least 65xx ...

I have got somewhat stalling project to emulate Z80 (well, 8080 for now) on 65xx (namely C64DTV, since it's faster and give more freedom with the help of memory paging and stack+ZP relocation possibility - what also can be done with 65CE02 as well). It'll be *slow* indeed. However if I understand correctly, somewhat "emulation" in used to emulate the 6510 behaviour of C64 in C65GS too in C64 mode, and the CPU speed may allow (with some extra features like linear RAM addressing in 32 or whatever bits?) to do it quite well even from the view point of decent emulated Z80 performance?

I think, numpad is matter of taste. Eg I never used that on PC either, and I would be happy to forget that on PC too. Eg it uses too much place on a notebook. But it's again what people are used to have. Some other people would be able to "kill" for numpad, I know The "deprecated storage technology part" is interesting, well, some can even say that a 8 bit system is also deprecated technology, and you can use a modern x86, ARM, whatever CPU instead. While the main purpose of Mega65/C65GS as far as I can see is to have a C65 after all (though with very major developments!), but still, a "retro" machine as a modern interpretation, and using floppy is also "retro" and part of the original C65. Ok, I have to admit, that I don't like floppies either Well, it seems everybody would love different things, and it's not easy to say that someone is "wrong" or "right", that's matter of taste, and this post was only my personal opinion, of course.