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Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
How about just using IX for referencing SP and just SET or RES bit 7 of IXH. Then IY can be the additional register pair to allow 16 bytes at a time, this solving the leftovers issue? -
Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... , pop BC to make flag register clear to use.
IX and IY as holders as ... -
Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... /> [QUOTE]How about just using IX for referencing SP and just ... IY can be the additional register pair to allow 16 bytes ... -
SE Basic IV Buffy v4.1 source (WIP)I've been doing a major refactor on the SE Basic source and I'd appreciate a code review from anyone who has time to look at it. I've almost certainl…
... /> exx ; main register set
ret ... DE
push ix ; IX
pop ... -
Cross platform developmentI'm just vaguely considering supporting a few more retro 8 bit platforms for something I have in mind to do. Just Z80 and 6502 really, but that cove…
... /> ; uses : af, bc, de, hl, ix
ld a,d ... parameter to be passed by register instead of via stack.
Cross platform developmentI'm just vaguely considering supporting a few more retro 8 bit platforms for something I have in mind to do. Just Z80 and 6502 really, but that cove…
... are indexed off the ix or iy register?). It's easy enough ... can't access the flags register from just C without some ... via the accumulator or another register though so nice and cheap ...IX register - using/problemsAre there any rules on using the IX register? Are there any restrictions on the memory locations that it can access? Yes, I know it's slower than us…
... as the Z80 is concerned IX and IY are tweaked ... there's nothing inherrent about IX or IY that would ... br />
The fact that IX and IY are internally handled ... because it would need the ix AND iy prefixes, but ... says use ix so you can't access the h register
IX register - using/problemsAre there any rules on using the IX register? Are there any restrictions on the memory locations that it can access? Yes, I know it's slower than us…
Putting certain values in I will crash an old school 128 or grey +2, but that has nothing to do with IX or IY as these are all totally different registers - though it's easy to see how the confusion arises given the way register pairs are usually named.Converting 'normal load' to fast loadCan someone recommend some programs / solutions to do this? I know you could get programs to do this 'back in the day'. Just wondering what the moder…
... 's games used the split IX/IY register instructions to make it ...Converting 'normal load' to fast loadCan someone recommend some programs / solutions to do this? I know you could get programs to do this 'back in the day'. Just wondering what the moder…
... 's games used the split IX/IY register instructions to make it ...IX register wonderings...***noob alert*** I'm doing a lot of these in my program: ld a,(ix+n) cp 0 jp z I know you can do things like this: dec (ix+n) but can you test …
... this valid:
dec (ix+n)
jr z, somewhere ... , you usually simply use a register as a loop counter. You ... for it, yet pointed by IX.IX register wonderings...***noob alert*** I'm doing a lot of these in my program: ld a,(ix+n) cp 0 jp z I know you can do things like this: dec (ix+n) but can you test …
... , you usually simply use a register as a loop counter. You ... for it, yet pointed by IX.[/QUOTE]
It's ... /> Not often needed and no register changes.Is ESXDOS flexible enough to incorporate e.g. Spectranet commands?I was just discussing the idea with someone about the wish some people have to be able to combine interfaces such as DivIDE (Plus) / DivMMC EnJOY! wi…
... handled is a structure in IX that describes the file being ... and identified in the A register.
[code]
__stdio_memstream_driver ...Using the stack to blit bufferI was using a ldir to blit my back buffer to the screen RAM, and it was working pretty well if not rather slow. After reading about using the stack …
... [/B] doesn't exchange AF register pair with its alternate version ... /> And don't forget that IX and IY can't be ... as they have no alternate register.We could design the LokiWouldn't it be great... if this community would develop what Sinclair himself started but was never finished: a successor of the 128K with 'cartoon l…
... wide addressbus, 4 complete Z80 register sets (i.e. 4 of ... , HL, AF', BC', DE', HL', IX, IY, all 32 bit wide ...JP (HL) confusionokay.... JP nn will jump to memory address nn. JP (HL) ,I assumed would read the contents of memory address HL and jump to the location and be a gre…
... simplicity, especially given that IX and IY cannot be accessed ... using the Z80's IX and IY instructions you' ... entertaining memory contention heaavily affecting register-pair operations and indexed ... allow instructions such as 'ADC IX,SP'. Presumably there wasn' ...JP (HL) confusionokay.... JP nn will jump to memory address nn. JP (HL) ,I assumed would read the contents of memory address HL and jump to the location and be a gre…
... allow instructions such as 'ADC IX,SP'. Presumably there wasn't ... directs accesses to HL to IX/IY, and then just continues ... that treated every register as a general-purpose register and every 16 ... -bit register as an index ...FZX: a new standard format and driver for proportional fonts[B]FZX[/B] is a very compact and efficient (although extremely flexible and powerful) standard format to create new fonts for the ZX-Spectrum. It sup…
... - and Boriel's system uses IX for tracking variable space. I ... shame that a very useful register is tied up for basic ... /> Basically, you have to push IX at the start, and change ... POP to recover the index register.
After that tweak ...FZX: a new standard format and driver for proportional fonts[B]FZX[/B] is a very compact and efficient (although extremely flexible and powerful) standard format to create new fonts for the ZX-Spectrum. It sup…
... Basically, you have to push IX at the start, and ... POP to recover the index register.[/QUOTE]
A ...
[CODE]ROUTINE:
push ix
call FZX_START
pop ... ix
ret[/CODE]
FZX: a new standard format and driver for proportional fonts[B]FZX[/B] is a very compact and efficient (although extremely flexible and powerful) standard format to create new fonts for the ZX-Spectrum. It sup…
... In comparison, temporarily changing IX inside this routine should have ... like boriel basic, uses IX as a framepointer. The library ... machines that need one index register reserved? They're screwed, ... The other version saves IX around affected library calls ...Double-Buffer ScreenFor my Alien Breed Speccy re-write I decided to use a Double Buffer (DB) or 'Back Screen' to draw all the game action onto, before shuffling the whol…
... through them with a spare register like IX.
Also there ... Stack Pointer as an extra register and read/write two bytes ... ' to swap to the alternate register set for another 8 bytes ...Sorting BusinessThis is a little bit different from the usual game-related fare but I know there are a few people here who like this sort of thing. This is about so…
... br /> ; bc = size
; ix = compare
; stack = array_hi ... br /> ; bc = size
; ix = compare
; stack = array_hi ... br /> ; bc = size
; ix = compare
; stack = array_hi + ... set. The R register is there, but ...llvm-z80 statusFew months ago I read about efforts to produce llvm back-end for the Z80 (even perhaps as part of new z88dk). Any update on that? I found [URL="htt…
... @ function
main:
push ix
push de
push ... bc
ld ix, 0
add ix, sp
ld ... subroutine means each subroutine has register allocation done in isolation and ...llvm-z80 statusFew months ago I read about efforts to produce llvm back-end for the Z80 (even perhaps as part of new z88dk). Any update on that? I found [URL="htt…
... it can use one index register either IX or IY. It is ... written to use IX but an assemble-time switch ... s why we can "use" IX (actually IY) without saving ... it for sdcc. The IX version of the library is ... 1.3&view=markup"]IX version of sdcc vfprintf ...RE: Skoolkit, Help neededHi all, Can anyone kindly tell me how to with an exact python prompt, convert a file from C:\games\exolon.sna to a skool file then into an asm file.…
... Manic Miner disassembly is a register table, which is produced by ... /docs/skoolkit/control-files.html#register-values"]R directive[/url] rather ... :
[code]
R 37562 IX Address of the message
Divide by 16 problem...I think.I *think* I have a problem with division. Now, this is not for the Spectrum but it [i]is [/i]for another Z80 platform. I'm converting [b]Speccies …
... 't have indirect and indexed register addressing instructions either (like [b ... ]LD A,(IX+10)[/b]) when the destination ...New SpecEmu<span style="font-family: Arial, Verdana; font-size: 10pt; line-height: normal;">Finally a small update available </span><a href="http://homepage.ntl…
... as it's an x86 register, so using "_SP" :p
AFalt z80regpair
IX z80regpair
IY z80regpair
Game development guidesHello all, I want to get into game development for the ZX Spectrum and would like to know where I can find some helpful guides. I've looked around t…
... are not allowed to change ix and iy in your ... where the library uses ix (it must save ix if it uses ... does not have to save ix and sdcc is invoked with ... causes the assembler to swap ix and iy in the assembled ... the asm entry point with register API from the c entry ...Internet enabling a SpectrumHi, Yonks ago, I floated the idea of using one of these: http://www.mycal.net/old/wsweb/img/s7600a.pdf ..to Internet enable a Spectrum. I d…
... directory to hold the asm register interface to functions. Another directory ... if you use one index register most of the time you ... correspond to your code using ix and sdcc_iy will correspond to ... is supposed to use ix as its index register).
The ...Emulator developmentHi, Could anyone explain or direct to a link that explains in not to technical terms how an emulator is developed. It has always blown my mind eve…
... , E, H, L, R, IM, IX and IY (the last two ... second set representing the shadow register set.
Then you ... and pop them into a register, move PC to somewhere else ... an arithmetic operation on a register or value, or write values ...
