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Machine Code: quicksort optimisationI came across this z80 quicksort implementation when going through the wikipedia article on the same. It's 44 bytes long. I was wondering if any of …
... ld de,0
push de ; mark end of ... for pending qsorts
pop bc ; bc = left< ... ; if 0, done
pop hl ; hl = right
inc bc
push bc ; stack = left+1 = ... -
Screen DisolveHas anyone got any good assembly code to dissolve the screen I could see
... . of lines
lb597: push de
ld a,4h ...
jp nz,lb59a
pop de
inc d
128k Screen Flipping - Sample Code PleaseI know this has been covered before, but I cannot find out code to do the following: On a 128k Spectrum tell the speccy to display from address 4915…
... (renderpage),a
pop af
ret
PageRam: push bc
push de
... a
pop de
pop bc
...Any examples of Proportional Font (Dark Star)Dark star had a cool proportionally spaced way of displaying text. Does anyone know of any code to do this? Cheers
... ,8
a1:
push bc
ld ... ,a
a2:
push de
ld a ... />
inc h
pop de
inc de
pop bc
djnz a1
Run Length DecodingRun length encoding/decoding is far less efficient than using a modern compression program.
... /> jr z,del1
del2: push af
ld a,0 ...
jr z,del3
pop af
dec a
jr del1
del3: pop af
retRun Length DecodingRun length encoding/decoding is far less efficient than using a modern compression program.
... ), a
push af
call slow_downhl
pop af
dec ... , 96
pop hl
inc l
push hl
. ... nz, unpak_scr4 ;last col ?
pop hl
ret
pop hl
inc l
push hl
. ...Timex 80 column display driverI subsequently wrote an 80 column font driver for 512x192 mode.
... /> push af
and #18
ld e,a
pop af ...Has this been done before?Are there any emulators whose speed can be adjusted by the Spectrum program that the emulator itself is running? So that, say the Spectrum program ca…
... A,A
@1:
PUSH IX
CALL @ChangeSpeed
@ChangeSpeed:
POP IX : DEFB #ED,#FE
LD (RestoreSpeed+1),HL
POP IX : RET
-------------------- 37 bytes ...Speccy 128k Double Buffering.If I understand this right, you display either of the screens, and draw to the one that is not being displayed. Am i right in thinking that the Non …
... /> pop de
pop bc
pop af
ld sp, screenptr
push ... af
push ... bc
push ...ANN: SP1 for Z88DK (aka splib3, Sprite Pack v3.0)Well it's finally arrived, after a month of "a few days from now" release deadlines. SP1 is the lastest version of splib, a flicker-free software sp…
... ; you PUSH a dish on top of the stack and POP one ...Sprite adviceHello. So, I'm slowly getting to grips with Z80 assembly - currently equal parts frustration and enjoyment. Now looking for some advice to help shift…
... positions in stack -
push de ;they will later become ...
call xorsprite
pop de ;retrieve new hl and ...
call xorsprite
pop de ;retrieve new hl and ...
call xorsprite
pop de ;retrieve new hl and ...Sprite adviceHello. So, I'm slowly getting to grips with Z80 assembly - currently equal parts frustration and enjoyment. Now looking for some advice to help shift…
... :-
[code]
spritedraw push bc
ld l,(ix ... set to 1, though: 1 push, 1 pop, no loop.
Many ...Loading schemes18 years ago I hated loading schemes like Alcatraz and Speedlock because they were a b*tch to copy and became unreliable when the tape got older. Now…
... ld de,40000
push de
ld hl,$ ... jp nz,loop
pop de
dec d< ... call z,llll
pop af
jr lff41< ... /> djnz lop
pop de
inc de< ...Calling ROM routinesFirstly, sorry if this is the wrong forum to post this in, but I wasn?t quite sure under which heading is best fitted. I?m trying to figure out how…
...
LD BC,(23645)
PUSH BC
; Put 35000 ... /> ; Restore old CH ADD
POP BC
LD (23645),BC ... BC then RET
PUSH HL
POP BC
RET ...Restore Registers Returning to BASICI should really know this, but I've not written code that requires a return to BASIC for a loooong time. What registers need to be preserved / resto…
Given that the stack must be preserved, you can just PUSH HL before saving the stack, and POP HL after restoring it.Restore Registers Returning to BASICI should really know this, but I've not written code that requires a return to BASIC for a loooong time. What registers need to be preserved / resto…
... can just PUSH HL before saving the stack, and POP HL after ...In Machine Code, what is the quickest way to sort bytes?I am playing around with some ordering of sprites, where I want to order them by vertical position. I used some Rodnay Zaks code to order some bytes…
... ; col4% = col3% + col1%
push de
ld hl ... /> ld (hl),a
pop de
ld a ...
sort2: pop de
sort3: inc ...Pimp my code...Erm, this is just the result of a mental exercise - I wanted to repeatedly display a UDG but decided against using a ROM routine and UDGs! Any sugges…
... 't need to do the push hl / pop de / inc de if ... b,8
loop:
push bc
ld a,(ix ... bc,0x0100
ldir
pop bc
djnz loop
Pimp my code...Erm, this is just the result of a mental exercise - I wanted to repeatedly display a UDG but decided against using a ROM routine and UDGs! Any sugges…
...
[code]
push hl
pop de
[/code]
push de
push de
push de
push de
push de ...
push de ...SjASMPlus cross compiler of Z80 assembly languageHi! I want to present you cross-compiler of Z80 assembly language: [B]SjASMPlus[/B]. [SIZE="4"]Features:[/SIZE] [LIST] [*]Z80/R800 documented and un…
... code (fast backbuffer printing using POP/PUSH, etc).
[QUOTE=Metalbrain ...Games that are impossible to complete due to bugs!I'm trying to compile a list of Speccy games that cannot be completed because of a bug (or simply bad programming)! Here's a few... [B]Frankie Goes …
... /> LD (IY+0),8
POP HL
LD E,LX ... +0),8
POP HL
PUSH IX
POP DE
LDI ...Xenon TriOxide (Xeo3)I just wanted you all to know that a new cross platform game has started development (well the +4 version has been around a while, but my colleague f…
... br /> [code]
push hl ; 64009
... djnz l_fa0c ; 64015
pop hl ; 64017
ret ... l_fa16 ; 64029
pop hl ; 64031
ret ...Oh so BRIGHT!What is the SLOWEST way to change the attribute area to BRIGHT? It has to be legit! No meaningless instructions or doing stuff for the sake of it. …
... />
incattr: push bc
di
nextattr: push ix
pop hl
ld ... ,de
push hl
pop ix
...Rst #38This, as far as I know, is the ROM procedure that does the keyboard check. (and, at the same time, is what's being executed by interrupt in IM 1 mode…
...
;; MASK-INT
L0038: PUSH AF ; Save the registers that ...
;; KEY-INT
L0048: PUSH BC ; Save the other main ... registers.
PUSH DE ;
... Restore registers.
POP HL ;
POP AF ;
EI ...The BASIC ISRFirst of all, excuse me if my blatant ignorance about this topic makes me write some nonsense :) The thing is that I'm finishing a game in mixed BAS…
... /> org $fefe
push af
push bc
push de ; store needed ... play music
pop de
pop bc
pop af
jp ...tips on optimizing assemblyI wrote a small routine to rotate right a whole screen character line complete with attributes. This is my third ever assembly routine, so I guess i…
...
scanline:
push hl ; save column 31 address ... pixel row
ldd
pop hl ; restore column 31 address ...Urgent Help needed to fix this: calling all machine code gurusI am currently trying to write tutorials on the amazing Orfeus music composer by Proxima which allows you to do multi channel music through the beepe…
... ,(hl)
pop hl
ret
l8c87: push hl
l8c92: ld a,(hl)
pop hl
ret
l8c95 ...
nop
nop
push hl
adc a,d ...
adc a,l
push hl
adc a,d ...tips on optimizing assemblyI wrote a small routine to rotate right a whole screen character line complete with attributes. This is my third ever assembly routine, so I guess i…
... affects P/V flag
push hl ; save column 31 address ... pixel row
ldd
pop hl ; restore column 31 address ...Help understanding some z80 asmI'm trying to work out how to represent the structure of a "sprite" in the SAM as "Grabbed" by SmallC. I can see the assembler implementation but I …
... /> push hl
call myfunc
pop bc
pop bc
pop bc ... /> pop hl ; hl = param1
push hl
push de
push bc
push ... ; de = param2
pop hl ; hl = param1
push af ; just put ...
