c64 > spectrum ?
I was recently talking to a c64 coder, (the guy who wrote mega apocalypse on 64) and he was telling me the speccy maker of the game used something to port the code from 6502 to z80, I guess it can only do some of it , due to the differences.. wonder if anyone has heard anything like that?
Post edited by fog on
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how this is are suppose to be?:???:
ah misunderstood the post... I can see it happening to quickly and accurately capture the original game logic, which is a portion of the program that normally consumes only a small part of the cpu resources. You can emulate the 6502 features on the z80 (eg the zero page) and can perform a simple translation of 6502 code to z80 code with careful mapping of z80 registers to 6502 registers but it will run more slowly, which maybe is ok for the game logic. The 6502 emulators around (eg for the hw sid players, etc) don't do this though -- they emulate each 6502 instruction via table lookup, rather than do any code translation, as for those sorts of applications you also have to worry about the memory map and interrupt mappings. And that, of course, is much slower still.
Write games in C using Z88DK and SP1
I remember being told something similar about a game. Possibly Aliens US.
There was no emulation involved, the code was converted manually with a Z80 register set aside for each of the 65xx registers and instructions replaced with an equivalent instruction/macro. Obviously a lot easier to do in that direction that it would be to try and convert it back.
why ? ;)
it's sales were greater than spectrum, so it's factual also :)
- IONIAN-GAMES.com -
Price for commode = 2 x Sinclair
2 x Sinclair = twice the price, not as nice :p
Mass = 15 loaves of Sunblest + 14 loaves of Allinson + 8 loaves of Mighty White + 1 Spar White Sandwich loaf x BROWN = Grey Monster.
I know which one I would've went for :D
Boozy is a mathmatical genius in disguise as a drunken geordie ;)
Instant sig, if ever there was one!
:lol:
Translating 6502 to Z80 is much easier than Z80 to 6502. What my code did was something like:
* 6520 A -> Z80 A
* 6502 X -> Z80 C
* 6502 Y -> Z80 E
* 6502 Tr1r2 -> Z80 LD r2,r1 eg TXA -> LD A,C
Off the top of my head I can't remember how I translated address modes like (zp),Y. abs,X and abs,Y I did with LD HL,abs:ADD HL,BC:LD A,(HL).
bet you owned an amiga though .. so you can't :D
(odds against you owning an Archimedes are high :) )
I own 2 Amiga's and YES I can ban you...
Watch out! Here comes an s...
go on then ...
...t owner! yep! 2 STs in fact, and 2 Amigas as well :p
believe the term is "put up or shut up"
one of you keeps mentioning they are gonna do that.. yet never do.. I find it more laughable it has to be keep being mentioned for no actual reason 90% of the time.
mentioning "I'm gonna ban you" the odd time for comedy value is 1 thing.. mentioning a lot more "because" it a bit more gets boring..
I wouldn't cry, sorry to disappoint . more than likely find it amusing, that they bothered to do what they keep commenting on.
If you're going to get involved in light-hearted banter than be prepared to take it as well as give it especially if it involves C64. This being a ZX Spectrum forum then it will always be biased, no major surprises there.
And I never said I was going ban you, I said can, I don't want to ban anyone.
We're all keeping it light except you...
Indeed :) C64 > Spectrum? Nobody should be allowed to talk about such obscenities as it only rises turmoil amongst meek Spectrum folk :)
FINISH HIM!
:P
Bytes:Chuntey - Spectrum tech blog.
Are you not entertained? :D