-
Push/Pop data copyingWe all know that stack pointer cheese and push/pop is faster to move data than LDIR - which in turn is slower than unrolled LDI's anyway. I rewrote …
... that stack pointer cheese and push/pop is faster to move ... use push/pop, but copying a four character sprite to the screen takes ... three cycles of push/pop.
... well if throwing over a screen buffer version instead, which ... -
ZXSCLZF - Yet another Screen CompressorQuick disclaimer before I continue, this compressor does not shrink screens as small as some of the others posted here, in particular the very good z…
... rest of the screen (good for cut scenes, pop ups etc...). It ... scans the screen memory by ... memory position to start the copy
push hl ; 11t - store ... ;;
;; copy L(b) bytes from one part of the screen to ... -
SP and IM2 woesI have a function that writes the backbuffer to the screen using the method by which SP is stored, I "POP" a load of registers and then chnge SP to t…
... the backbuffer to the screen using the method by ... POP" a load of registers and then chnge SP to the screen ... and "PUSH" them back.
... the IM2 interrupt, the screen gets corrupt (All it ... few cycles to do the copy of GFX.
Trouble with rainbow effect push/popI'm having a bit of bother getting my rainbow graphics to behave themselves. Basically I want a rainbow effect to last for say 4 seconds before movi…
... problem is if I omit push and pop bc the thing goes ... )
;push bc
call flash
call flash2
;pop bc ...Double Buffer UtilityHi Folks, I've been experimenting with double buffering on a 48k Speccy for a small project I'm working on. After reading lots of good advice here…
... left of the screen)
#
#Copy to screen y-position in ... POP HL']
self.copyPushList = ['PUSH HL','PUSH DE','PUSH BC\nEXX','PUSH IX','PUSH HL','PUSH ... self.destXPos = self.inputValue('Copy to screen x-position in (integer) ...[Asm] Is this nested loop faster than LDIR or a bunch of unrolled LDI's?Hi all. I'm learning Z80 asm on Speccy 48K, and to start with I decided to write my own "CLS" routine (without relying on ROM calls or LDIR) as a lea…
... .
; Clear screen memory.
ld a,%00000000 ... ; Move back to the previous screen address.
djnz cls_screen_loop ... going back to basic. Screen is cleared now, continue ... stack pointer and using push/pop to copy memory fully unrolled ...whats your second favourite retro computerOk i'm going to assume that for most of us here the speccy is our favourite number 1 retro computer,its the best home computer in the world etc etc :…
... byte to perform the copy and occupies 1.5 ... copied. Oddly enough, inserting "push/pop ix/iy" in there ... If I were to copy a Spectrum screen (6912) the unrolled ... figure) so it could copy approximately 5714 bytes in ... and 1MHz, able to copy about 2048 bytes, I ...How do I clear only a specific area of a screen (quickly) in machine code ?I'm looking for a machine code routine which will clear the first 20 rows of the Spectrum's display (or any number of rows or columns) . I have found…
...
PUSH BC
; Zero out 8 screen lines of ... screen line.
; Alternatively could get HL back by PUSH/POP ... and then INC H.
POP DE ... is different from the ROM COPY routine - not sure ...help sought with first foray into machine code - pixel scrolldownI have started to code my first machine code program, a simple roadrace game. I've based it around the pixel scrolldown routine in 40 Best Machine Co…
... = destination address for pixel row copy
ld h,d ; ... push hl
ldi x 32 ; repeat ldi 32 times to copy ... address for next pixel row copy
jp pe ... screen, scrolling by more than one pixel, or moving to a push/pop ...help sought with first foray into machine code - pixel scrolldownI have started to code my first machine code program, a simple roadrace game. I've based it around the pixel scrolldown routine in 40 Best Machine Co…
... the right order on the screen starting one pixel line higher ... each in comparison to regular push/pop). The "ld sp,hl; ld ... the row in the next copy operation.
The destination ... be done for the next copy operation as the stack is ...help sought with first foray into machine code - pixel scrolldownI have started to code my first machine code program, a simple roadrace game. I've based it around the pixel scrolldown routine in 40 Best Machine Co…
... kind of glitch on screen where part of a ... in the middle of the screen has scrolled but some ... 21 for regular push/pop and will decrease the copy speed from ... from the top of the screen to the bottom. To ... will see somewhere up the screen. This happens when the ...Fast screen writesI wondered what the faster than LDIR methods of writing to the screen were.
... stored in this sequence
push hl
...
screen buffer and special drawing ... xx T/byte
PUSH/POP in theory 10.5 ... kind of really fast copy routine, the fastest i ... was example of very fast push/pop copy routine. he uses it ...A scrolling starfield - help needed!I have been messing on my speccy again recently and tried to do a scrolling (parallax - maybe) starfield. I know how to scroll using machine code but…
... lines in the ZX screen
; Copy them in reverse order
ldir
pop bc
jr LineScrolledDown ... now points to required screen byte
PUSH HL
LD ...Brand new River Raid remake?one of my friend is trying to make a riverraid remake on flash just to have fun, I checked zx spectrum port of river raid. it is bad, really bad, jer…
... all the POP / PUSH instructions for every line of the screen - no time ... can be pre-setted before screen rendering starts (it can be ... )
then use loooooong push/pop/ld sp code to write ... it (i'm not saying copy it just check it sometimes ...Rainbow Generator for 48K Spectrum using PUSHThis is what I came up with from [B]gasman[/B]'s suggestions. It's stable in ZXSpin and ZX32 simulating a 48K Speccy. Anyone like to try it on the …
... /> nop
nop
; copy the colours
REPT 24 ... the stack pointer to the screen
push hl ; write 8 bytes ... /> pop iy
pop ix
pop hl
pop de
pop bc
pop ...Character scrollingOk, first I'd like to say that I'm not looking for a complete routine (but that might help) because I am hoping to write it myself and learn a bit mo…
... use PUSH/POP copy, uses LDIR, uses pre-calculated screen cell ... /> ; Char Down
; Adjusts screen address HL to move eight ... br /> ; enter: HL = valid screen address
; exit : HL ... /> ScrollDownLoop: ;copy a single char line
push bc
...Using the stack to copy memory blocksA [b]PUSH[/b] and a [b]POP[/b] instruction together take less time than two [b]LDI[/b], so long [b]POP/PUSH[/b] sequences are sometimes used to copy …
... gasman's example of push/pop copy used for multicolor or ... my description of push/pop copier from CHASE H. ... about PUSH/POP copy don't forgot contetion (and you copy to screen memory ... very often). having contetion penalty for one PUSH ...Push/Pop data copyingWe all know that stack pointer cheese and push/pop is faster to move data than LDIR - which in turn is slower than unrolled LDI's anyway. I rewrote …
... the same speed as a PUSH/POP copy. But there is no LD ... .
PUSHing to the screen in reverse order does create ... line-by-line down the screen, even if the actual row ... haven't got a hidden screen to work on.Push/Pop data copyingWe all know that stack pointer cheese and push/pop is faster to move data than LDIR - which in turn is slower than unrolled LDI's anyway. I rewrote …
... the same speed as a PUSH/POP copy. But there is no LD ... ,0x1011
ld sp,screen+0x0020
push hl ; 4T lost to ... /> push hl
push de
push bc
exx
push hl
push ...Your Views on... GhostbustersI dusted off the Master System version of this and inspired me to try out the Speccy version. It's a good game with it's strong and weak points. I …
... a big LDIR to copy it to the screen. Unfortunately it does ... up by using LDI or PUSH/POP. To fit in the small ... at the black control menu screen.
Assemble the code ...Your Views on... GhostbustersI dusted off the Master System version of this and inspired me to try out the Speccy version. It's a good game with it's strong and weak points. I …
... a big LDIR to copy it to the screen. Unfortunately it does ... up by using LDI or PUSH/POP. To fit in the small ... at the black control menu screen.
Assemble the code ...Tile based graphics and scrolling thingy...Here's my best attempt so far at a tile based rendering and scrolling routine. It draws in 22 8*8 graphics tiles along the top of the screen (junk i…
... /> i wonder if speeding up copy routine by roughly 3% is ... , the faster way is using push/pop for copy. not saying it is ... when background is copied to screen and sprites are put directly ... to screen. so next copying of background ...Fairlight's use of LDIRYS, comparing Fairlight and Nightshade, said: [quote]Fairlight is much more interesting even though the techniques that Bo Jangeborg uses for screen…
... /> pop hl
ld sp,hl
push bc
push de ... /> push de
push hl
sp2:ld sp,0
pop ... when copying to screen. thats where you get real benefit from push/pop copy.Fairlight's use of LDIRYS, comparing Fairlight and Nightshade, said: [quote]Fairlight is much more interesting even though the techniques that Bo Jangeborg uses for screen…
... expect the code for different copy widths could be quite different ... copying to screen. thats where you get real benefit from push/pop copy.[/QUOTE ...Fairlight's use of LDIRYS, comparing Fairlight and Nightshade, said: [quote]Fairlight is much more interesting even though the techniques that Bo Jangeborg uses for screen…
... copying to screen. thats where you get real benefit from push/pop copy.[/QUOTE ... ). So the main benefit from push/pop copy will be outside of contention ...Exilei\'m sure this has been brought up before but couldn't find a thread in 'New Game Ideas'. Why did the Spectrum never get a port of the BBC game Exile…
... to 2/3 of the screen, is 16K. That's half ... you do give up on screen buffering on a 128K then ... limited to a raster-chasing screen update so you've achieved ... ]Hysteria[/I].
[/QUOTE]
PUSH/POP copy with bank switch between fetch ...Exilei\'m sure this has been brought up before but couldn't find a thread in 'New Game Ideas'. Why did the Spectrum never get a port of the BBC game Exile…
[QUOTE=Fikee;613293]PUSH/POP copy with bank switch between fetch ... in the middle of each copy. It slows you down, but ... up by instantly paging the screen in once you're done ...
