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Machine Code ChallengeHere's a challenge for all you Z80 programmers. Points to be awarded for elegance and brevity. (I haven't got the solution either) HL addresses the …
... program size is 74 bytes. This compiles on my ...
; Process all bytes.
LD B,D ; Restore original B ... .
CALL Next_byte ; Process all bytes ...
HL_Store WORD ; 2 bytes.
Next_byte < ... -
Machine Code ChallengeHere's a challenge for all you Z80 programmers. Points to be awarded for elegance and brevity. (I haven't got the solution either) HL addresses the …
... /> searchfor0: inc hl
.....ld a,(hl)
.....inc a ... it was 0 originally)
.....ld a,(hl)
.....and c ... byte (in cy)
.....ld a,(hl)
.....djnz nextbyte ... br />
subroutine length: 30 bytes
[ This Message was ... -
Machine Code ChallengeHere's a challenge for all you Z80 programmers. Points to be awarded for elegance and brevity. (I haven't got the solution either) HL addresses the …
...
8003 0610 7 LD B,16
; Process all bytes.
8021 42 4 LD B,D ; Restore ... 803C 0000 HL_Store WORD ; 2 bytes.
Number ... -
adding colourThis my sound like a real stupid Q but when programing a picture how do i add colour like filling in shapes with colour. What kind of programming sh…
... at #5800 and is 768 bytes long.
You can ... /> org 60000
ld hl,#5800
ld bc,768
l1 ... ld (hl),255
inc ... hl
dec bc
ld a,b
or c ... -
Spectrum ROMI downloaded some text files (they are actually the spectrum ROM files but in text) which can be compiled using TASM (or soemthing). I read on WOS th…
... one of
the $FF bytes near the beginning has been ... quoted fault at L2199
ld (iy+$02),$01 ; should be ... -
Spectrum edge connectors and 'Dataman Softy S4'Hi, I moved this from the sales thread because it seems more appropriate...anyway... I was twerping around the idea of turning a Spectrum into a we…
... make a table of 257 bytes, starting at an adress where ...
LD A,#FD
LD I,A
LD HL,#FD00 ... ; TABLE
LD B,0 ... -
New SPIN 0.3a releaseHi all, here's the next version - mainly a maintenance release, with new bugs :) Here's what's new: V0.3a - Bugs and more tapes -------------------…
... , it just takes up fewer bytes to store one memory location ... and six bytes than two memory locations and ... five bytes.[/quote]
This is what ... /> EF15 DEFW #15EF
3E20 LD A,#20
D7 RST ... -
ZX-2-PC Interface : Is it dead ???Certainly not, but I had some problems getting the EPROM-reader constant. In my former threat I stated that it worked, well, it read ROM-values but n…
... to load a block of bytes and at #04c2 to ... save a block of bytes. All the other work is ... e:
[code]
LD IX,32768 ; START OF DATA ...
LD A,255 ; Signal of DATA ... -byte
LD DE,16384 ; LENGTH OF DATA ... -
Basic and AY musicis it possible to play an ay-music in background while a basic program is running?
... />
DI
LD HL,HIGHBYTE ; table
LD DE,HIGHBYTE + 1 ...
LD BC,257
LD A,VECTOR ... ; IM2 vector
LDIR
LD I,HIGHBYTE
IM2
bytes to play with before end ... -
Horizontal scrollDoes anyone know how to do a 2 or 4 pixel left or right horizontal scroll of the spectrum screen. I can make a 1 one pixel scroll with: ... rl (hl…
... lscrsp: di
ld (temp_sp),sp
ld sp,hl
... 512;32*16
ld b,128
lscrsp10 ... do this because the bytes are in reverse order ... br />
ld hl,(temp_sp)
ld sp,hl
... -
Finding the length of loaded Bytes:Is there a way from BASIC of finding out how big a block of bytes loaded from tape was? i.e. - if you do LOAD""CODE and load in a lump of bytes, ca…
... .
LD IX, START
LD DE, 65535
SCF ...
CALL #556
LD HL,65535
XOR A ... />
HL = length + 2 bytes
Proload DE with 65535 ... -
Speccy machine code info where is it?Recently I've been trying to learn Z80 and I've managed to make limited progress (some of my routines even compile now!) but I seem to be having trou…
... (pressed or not):
ld a,0111 1111 ; row #7 ... the same thing:
ld bc,$7ffe
in a ... to get the 8 udg bytes on screen. There is a ... -
Advice about drawing sprites on spectrum I've coded sprite drawing before and know all the theory about masks from a long time ago (microhobby rules! ;), but since I did it on Amiga with ha…
...
pop l
ld a,(hl)
and (ix ... l
or (hl)
ld (ix+0),a
inc ... /> but with proper carry from bytes to bytes. -
Advice about drawing sprites on spectrum I've coded sprite drawing before and know all the theory about masks from a long time ago (microhobby rules! ;), but since I did it on Amiga with ha…
...
pop l
ld a,(hl)
and (ix ... l
or (hl)
ld (ix+0),a
inc ... /> but with proper carry from bytes to bytes.
[/quote]
Advice about drawing sprites on spectrum I've coded sprite drawing before and know all the theory about masks from a long time ago (microhobby rules! ;), but since I did it on Amiga with ha…
...
pop l
ld a,(hl)
and (ix ... br /> or (hl)
ld (ix+0),a
... /> but with proper carry from bytes to bytes.
[/quote]
... pop bc
ld l,c
ld a,(hl)
...Who want to remake Double Dragon?Seeing as the Speccy version was crap (see my review: [url="http://www.gamestyle.net/retro.php?article=31"]http://www.gamestyle.net/retro.php?article…
... />
di
ld (restore_sp+1), sp
ld sp, table line ... pe, next_line
restore_sp: ld sp, 0
ei
(1+3)*6144/2 = 12288 bytes
....
Anyone for a hacking challenge ?I have to get the DSK version of Tomahawk to work. It uses the well-known Digital Integration "SECURITY CODE" lock just like in Bobsled, ATF, etc. Th…
... would look thus...
LD A,3 ; Load Accumulator with ... 3
LD (40000),A ; Store contents of ... number of lives:-
LD A, (40000) ; Load Accumulator with ... to game over routine
LD (40000),A ;
...Sync-buzzer, interrupts and general confusionBeen wittering on about this in the Misc group, but thought it was best discussed here. Basically been trying to recreate the Sid-Sound effect from A…
... /> ld hl,$f000
ld de,$f001
ld (hl),$f1
ld bc ...
ldir
ld a,$f0
ld i,a
im ... interrupt vector table is 257 bytes long and occupies addresses 0xf000 ...help in byte mirroring.I need some help. What is the best way to mirror the byte? (for ex. 10010011 -> 11001001) I mean, if there is a simple way to do it (may be with OR, …
... really:
LD B,normalbyte ; gonna mirror this ...
LD A,B
AND 129 ... 129 ; swap bits
LD C,A ; storing it here ...
nxt0 LD A,B
AND ... RL B, which is three bytes IIRC - repeated eight times ...help in byte mirroring.I need some help. What is the best way to mirror the byte? (for ex. 10010011 -> 11001001) I mean, if there is a simple way to do it (may be with OR, …
... :
LD A,normalbyte
LD H,tablehighbyte
LD L,A ... ; tablelowbyte
LD A,(HL ... competition there - you loose 256 bytes in a table but you ... mirror you can sacrafice 256 bytes which is a lot less ...Tough paging questionOK... Take this: 1. We have a program compiled and run from within GENS under a Pentagon 128K environment. 2. The program works perfectly. 3. We sav…
... for screen flipping (first 6912 bytes of each)
The ... always prefer ye goode olde LD BC, #7FFD; OUT (C),A ...Tough paging questionOK... Take this: 1. We have a program compiled and run from within GENS under a Pentagon 128K environment. 2. The program works perfectly. 3. We sav…
... for screen flipping (first 6912 bytes of each)
Just ... always prefer ye goode olde LD BC, #7FFD; OUT (C),A ...Z80 coders compoIf you're interested in Z80 coders compo, visit my page [url="http://mbr.nm.ru/compo.html"]http://mbr.nm.ru/compo.html[/url]
... beyond, is 38 bytes.
.test
ld hl,40002 ; destination ...
.convert
ld bc,$030f ; b = 3 decimal ...
This one is 38 bytes in length, with my other ... algorithm at 44 bytes so there are 6 bytes to play ...Z80 coders compoIf you're interested in Z80 coders compo, visit my page [url="http://mbr.nm.ru/compo.html"]http://mbr.nm.ru/compo.html[/url]
... solution #3, about 53 bytes using a more BCD ... />
.convert
ld bc,$0300 ; 3 decimal digits ... = BCD(10*7654)
ld c,a ; c = hundreds ... position BCD
ld a,d ; a = BCD( ... $30 ; add '0'
ld (hl),a ; store ascii digit ...AssemblageCan any of you marvellous programmers out there recommend a Speccy assembler that even a complete dunce could use? At the risk of sounding thick, as…
... is only one byte. The ld bc, instruction expects two. Hence ... =99, BC=99
Bytes are ordered least significant first ...Z80 coders compoIf you're interested in Z80 coders compo, visit my page [url="http://mbr.nm.ru/compo.html"]http://mbr.nm.ru/compo.html[/url]
... necessary)
; total size: 24 bytes
ORG #6D11 ... #2E ;XX1E == LD L,(STORE+2)%256 = LD L,#2B
LD A,(HL) ;XX21
...New project for 256 colours Games emulator!O.K. , I suggested Jonathan Needle ( Creator of the excellent Spectaculator at [url="http://www.Spectaculator.com"]www.Spectaculator.com[/url] ) to c…
... does is to copy graphics bytes from a bit of memory ... program does (say)
LD HL,(graphics data)
JP ... A after (say)
LD A,(graphics data)
INC ...New project for 256 colours Games emulator!O.K. , I suggested Jonathan Needle ( Creator of the excellent Spectaculator at [url="http://www.Spectaculator.com"]www.Spectaculator.com[/url] ) to c…
... does is to copy graphics bytes from a bit of memory ... program does (say)
LD HL,(graphics data)
JP ... A after (say)
LD A,(graphics data)
INC ...help in byte mirroring.I need some help. What is the best way to mirror the byte? (for ex. 10010011 -> 11001001) I mean, if there is a simple way to do it (may be with OR, …
... is,
ld b, n 7T or ld b,(hl) 7T ...
ld a, 255 7T ... only 14T states and 5 bytes.
I think it works ...ZX81 ScrollingI'm tempted to have a go at a bit of ZX81 programming, using MCODER II, though I could really use a fast multi-directional scrolling routine. Does a…
... screen needs to lower 33 Bytes and add
32 ... br />
[code]
LD HL,(VAR FOR ENDSCREEN)
LD DE,(VAR FOR BEGINSCREEN)
... HL,DE
LD B,H
LD C,L
... DE,HL
LDDR
LD (DE),#76
RET
