-
Edge Grinder, how would YOU do it?I always meant to post about this and AndyC reminded me in the 'vs' thread in games. [QUOTE=AndyC;808887]The thing I love about threads like this is…
... HL,BC
; copy the character letter to the screen
LD DE ... />
POP HL ; recall stuff
POP DE
POP BC
Help for beginner with z80Hi chaps, I'm reasonably new with z80, but had a fair amount of experience with 68000, so decided to give a few things a go. One little thing I'm t…
... HL,BC
; copy the character letter to the screen
LD DE ... />
POP HL ; recall stuff
POP DE
POP BC
Small Machine Code Routines Which Maybe UsefulAs part of creating Flynn's Adventure in Bombland I created a lot of little routines to do all sorts of things. A lot of these I created based on inp…
...
ld a,(fontcolour)
ld (hl),a
pop de
ld a,c ... : ;arrive DE pointing at screen, HL at graphic
ld bc,(charhalf) ;8 in ...
pop de
ret
;
cls: ld hl,16384
ld d ...Variable sized tiles /tile routineHow would you do a variable sized tile routine where the tiles have position variables too? Thanks would be interested to learn :)
... print all the graphics on screen that are in the table ... />
call printblock
pop hl
inc hl
jp buildlocation
hl, hl
add hl, bc
ld a, (hl)
inc hl
ld h, (hl)
ld l ...128K programmingDoes anyone know any good resources on assembly programming for the 128? All I'm after is an "idiot's-getting-started-guide" on how to utilise the…
... HL
LD (HL),000
DEC HL
LD (HL),081
LD SP, HL
LD BC,32765
LD ... (video memory) as a temporary buffer. Data are transferred in chunks ...Disappearing/appearing effectI remember doing a small routine in BASIC which could be used to cover the attributes section randomly, until all 704 characters were filled with the…
... whole screen.
[code]
org 32768
di
ld bc,2048 ...
loop: push bc
call random
pop bc
ld a ... /> add hl,hl
add hl,hl
ld c,h
ld hl,(seed)
ld b ...Let's copy buffers!Figured I'd do some double buffered graphics, so I can render for several frames before displaying stuff. Yes, I mean on a 48k speccy, so no 128k spe…
... (BC is pre-loaded):
[code]
ld sp, hl
pop de
pop ... /> exa
pop af
pop bc
pop de
pop hl
ld sp, #(constant value ...Let's copy buffers!Figured I'd do some double buffered graphics, so I can render for several frames before displaying stuff. Yes, I mean on a 48k speccy, so no 128k spe…
... screen address from lookup table
next:
ld sp, hl
pop ... ix
inc hl
inc hl
... inc l
inc hl
ENDIF
...Let's copy buffers!Figured I'd do some double buffered graphics, so I can render for several frames before displaying stuff. Yes, I mean on a 48k speccy, so no 128k spe…
... screen address from lookup table
next:
ld sp, hl
pop ... ix
inc hl
inc hl
... inc l
inc hl
ENDIF
...Proportional fontsI've been doing some proportional font drawing, purely on C level at the moment, but it's orders of magnitude slower than I'd want it to be. It's sti…
... the relevant bit on screen according to the ...
ld hl,fe8fh
ld c,(hl)
push hl
print ... /> db 00h,80h ;ld de,current char in text ...
ld a,(de)
...How can I make a UDG rotate?I designed a set of UDG's that can be used for making shapes or letters. Trouble is that my circle - for example - consists of 4 pieces and it would…
... INC HL ; and move HL to the next screen byte
LD A ...
POP BC
POP BC
LD B,0
LD C,A ...printing to the screen using pokei remember there being a way to print to the screen using pokes, which would allow you to print a character anywhere in the 175x255 matrix. can anyon…
... are talking about.
LD SP, (23613)
CALL 7289
LD HL, 23705
PUSH BC
PUSH HL
CALL 7828
POP HL
POP BC ...
LD (HL), A ...Kempston Mouse DriverHi Folks, Does anyone know the email of Chris Cowley who wrote the Kempston Mouse Driver in the WOS Archive? Many thanks Paddy
... /> LD B,A
INC HL ; and move HL to the next screen byte ...
LD A,L ... 255
POP BC
POP BC
LD B,0
LD C,A
Is it possible to run a single BASIC line via a ROM CALL of the Standard ZX 48k ROM?On: https://cygnus.speccy.cz/popis_trdos-assembler.php I found the following code: [code] CHADD equ 23645 ; Location of SOS variable CHADD ld…
... ld hl,commandline
havelines:
ld ($5C5D),hl ; CH_ADD
ld bc ...
ld bc,return
push bc
ld ($5C3D),sp ; update ...
exitgoto:
pop bc
ld ($5C3D),bc ; restore orginal ERR_SP
Is it possible to run a single BASIC line via a ROM CALL of the Standard ZX 48k ROM?On: https://cygnus.speccy.cz/popis_trdos-assembler.php I found the following code: [code] CHADD equ 23645 ; Location of SOS variable CHADD ld…
... /> ld hl,commandline
ld ($5C5D),hl ; CH_ADD
ld bc,($5C3D)
push bc ...
ld bc,return
push bc
ld ($5C3D),sp ; update ...
exitgoto:
pop bc
ld ($5C3D),bc ; restore orginal ERR_SP
What to write / programme?I've been trying to get back some motivation to write something in machine code for the Spectrum. I don't feel I am organised enough to write somethi…
... one will fill the screen with a user defined ... uses a table of screen addresses of the ... bc
ld a,(hl)
ld e,a
inc hl
ld a,(hl)
ld ... pop bc
inc e
djnz loopb1
pop hl
pop bc ...What to write / programme?I've been trying to get back some motivation to write something in machine code for the Spectrum. I don't feel I am organised enough to write somethi…
... 24 UDG's. The screen table just holds the ... bc
ld a,(hl)
ld e,a
inc hl
ld a,(hl)
ld ... br />
pop de
pop bc
inc e
pop hl
pop bc
dec c
...Robospec (new project, hopefully useful as a tutorial as well)Starting a new project after my graphics investigations. * It's gonna be a Robotron clone since that's not too ambitious (although I'd like to hav…
... /> ; look up screen address from the table
ld a, (hl)
inc ... of screen
ret z
ld a, c
xor (hl)
ld (hl ... /> add c
pop bc
ld l, a
ld a, e
Robospec (new project, hopefully useful as a tutorial as well)Starting a new project after my graphics investigations. * It's gonna be a Robotron clone since that's not too ambitious (although I'd like to hav…
... /> ; look up screen address from the table
ld a, (hl)
inc ... of screen
ret z
ld a, c
xor (hl)
ld (hl ... /> add c
pop bc
ld l, a
ld a, e
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
...
pop af ; don't return pointer to buffer in hl
ld a ... , TAG_INT16
ret
.returnstr
pop hl ... de, hl
push bc
call parseint16
pop bc
ld a, c ...FAST PIXEL DRAWINGI'm looking for the fastest way to put a pixel to the screen (on spectrum ofcoz:). Here is my own procedure (written in PASMO). But I don't how do it…
... put a pixel to the screen (on spectrum ofcoz:). Here is ...
ld c,a
ld a,(bc)
ld b,(hl)
or ... b
ld (hl),a ...Pixel setting / general speccy codingi just started doing some cross-coding with the [url="http://www.bigfatpanda.fsnet.co.uk/z80.html"]Z80 SNA assembler[/url] and an emulator, and this …
... a pixel at a given screen coordinate:
[code]
ld c, a
add hl, bc
ld b, (hl)
ex de, hl
ld ... a, (hl)
xor ...DEC BC/LD A,B/OR C/JP NZ,loopyesterday i saw nice trick:[code] dec bc ld a, b or c jp nz, loop can be replaced (bc starts >255, short jump) by: dec bc inc b djnz loop [/code] …
yesterday i saw nice trick:[code]
dec bc
ld a, b
or c
jp nz, loop
can be replaced (bc starts >255, short jump) by:
dec bc
inc b
djnz loop
[/code]
..niceReturn of Speccy screen buffer formatI recently discovered that the Spectrum screen buffer format that allows only two colours in an 8x8 pixel block has made its return in a slightly dif…
... recently discovered that the Spectrum screen buffer format that allows only two ...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 …
... br /> ld (bc),a
ld a,h
ld (de),a
pop hl ;restore ... pop hl ;restore pivot
pop hl ;pop lo
push bc ;stack=left-hi
ld ...Question on copying screen bufferHi, Al my prevoius games were copying graphics directly to screen memory starting at 16384. Now I'm experimenting with screen buffer where I could d…
... . Now I'm experimenting with screen buffer where I could draw my ... I would copy it to screen memory.
You may ... just copying static image from buffer to screen after HALT.
A tidy loader for minigamesThe minigame competition doesn't permit the use of separate loaders like [code]10 LOAD "": RAND USR 32768[/code] The loader must be included in the b…
The minigame competition doesn't permit the use of separate loaders like
[code]10 LOAD "": RAND USR 32768[/code]
The loader must be included in the byte count.
In an attempt to save as many bytes as possible, people have written ...Optimize this assembly?Aiming for Variable*192 -> HL In the first case, I came up with the obvious method - *128 +*64: [code] ld a, (variable) ;13 ld h,0 ; 7 ld l,…
... ld l, a ; 4
add hl, hl ;11
add hl, hl ... hl, hl ;11
push hl ;11
add hl, hl ;11
pop bc ... /> [code]
LD A,(variable) 13
LD h,a ; A ... 256 4
LD L,0 ; L=0 7 ...CMWC random number generator for Z80Seeing the interest regarding the [URL="http://www.worldofspectrum.org/forums/showthread.php?t=23070"]Xor-Shift random number generator for Z80[/URL]…
... /> ld b,0
ld c,e
ld hl,table
add hl,bc
ld c,(hl) ; y = q ... - 1 = ~x
pop hl
ld (hl),a ; q[i] = x ...
