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Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... =SkoolKid;661292]Oh, and also SUB HL,DE and SUB HL,BC. Why were they ... , for example, SJASMPlus.
The fake instruction LD HL,DE for example ... and time a supposed LD HL,DE instruction would use (taking into ... -
Tutorial - learn machine code in 30mins[B][I]Message from the moderators[/I] - bigjon has requested that readers' attention be drawn to a better version of this tutorial, one which is easi…
...
We'd like to 'sub hl,de' but there's no such ... de,9
add hl,de
ld (hl),a
inc hl
ld (hl ... de,9
add hl,de
ld (hl),a
inc hl
ld (hl ... de,9
add hl,de
ld (hl),a
inc hl
ld (
bigjon
November 2009
Development
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Clearing the Carry flagI'm reading that sometimes I may want to clear the carry before using ADC or SBC. A simple AND A or OR B will do. However, as I see it, for 8-bit ar…
... / SBC than there are ADD / SUB ops. Although you can do ... no such option as:
SUB HL, DE
but there is
Tutorial - learn machine code in 30mins[B][I]Message from the moderators[/I] - bigjon has requested that readers' attention be drawn to a better version of this tutorial, one which is easi…
...
We'd like to 'sub hl,de' but there's no such ... de,9
add hl,de
ld (hl),a
inc hl
ld (hl ... de,9
add hl,de
ld (hl),a
inc hl
ld (hl ... de,9
add hl,de
ld (hl),a
inc hl
ld (
buzzy
September 2012
Development
Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... were versions of the ADD, SUB, ADC, SBC, XOR, AND and ... register, so why not ADD, SUB etc. too?
(Yeah ... />
Oh, and also SUB HL,DE and SUB HL,BC. Why were they missing???Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
[QUOTE]Oh, and also SUB HL,DE and SUB HL,BC. Why were they missing???[/ ... />
OR A
SBC HL,DE
Remember also that ...Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
...
Oh, and also SUB HL,DE and SUB HL,BC. Why were they missing ... to use ADD HL,DE to overflow as a SUB HL,DE replacement, or ... (or not) and do SBC HL,DE?
[QUOTE= ... instead of 'SUB' HL,DE (de is 32)
ADD HL,DE (de is 65504) gives ...The Pros and Cons of "alternative" assembler syntaxContinuing from [URL]http://www.worldofspectrum.org/forums/showpost.php?p=720754&postcount=72[/URL] [QUOTE=u6c87;720754]But that wouldn't change if…
[QUOTE=introspec;721102]SBC HL, DE?[/QUOTE]
But you can't SUB HL, DE. SUB only applies to A.The Pros and Cons of "alternative" assembler syntaxContinuing from [URL]http://www.worldofspectrum.org/forums/showpost.php?p=720754&postcount=72[/URL] [QUOTE=u6c87;720754]But that wouldn't change if…
... 721106]But you can't SUB HL, DE. SUB only applies to A.[/QUOTE ... /> DEC BC BC-
INC (HL) [HL]+ [H]+ M+
DEC ( ... HL,BC HL+BC H+BC H+B HL+B
ADD IX,DE ... X+DE ... X+D
SBC HL,HL HL-*HL HL-*H
...Sort 2 byte words (x, y) on ypos, also question about swap (DE), (HL)Well that was a lot of debugging ;) But if you want a routine which takes an array of 16 byte words x, y and then sort them on y (ignoring x), I'm…
...
push hl
add hl, de
pop de
ex de, hl
swap_word ... /> // Recursively heapify the affected
// sub-tree
heapify(arr, n ...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…
... [*]Fake instructions as LD HL,DE (LD H,D:LD ... http://prdownloads.sourceforge.net/sjasmplus/sjasmplus-win32-1.07-rc5bf2 ... http://prdownloads.sourceforge.net/sjasmplus/sjasmplus-win32-1.06- ... http://prdownloads.sourceforge.net/sjasmplus/sjasmplus-freebsd-1.06-stable ...Sprites masterclassHi All, You guys are probably tired of explaining sprites but I'd like to clarify a few things if possible. I've sorted the vertical aspect of scro…
... .
(The code is SjASMPlus compatible)
[CODE] org ...
ld a,192
sub b
ld d,a ... l
ld de,sprite1
add hl,de
push hl
pop ...
ld a,192
sub b
get_spdata1 push bc ...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…
... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + FONTBASE ...
; restore DE ... a
add hl, de
ld a, (hl)
or a
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…
... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + FONTBASE ...
; restore DE ... a
add hl, de
ld a, (hl)
or a
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…
... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + FONTBASE ... /> ld (de), a
; negate hl
xor a
sub l
ld a, (hl)
cp '''' ; SjASMPlus uses '' as escape code ...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…
... call make_nil_cpair
ex de, hl ; DE has address of int16: 3 ... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + ... FONTBASE
; restore DE ...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…
... call make_nil_cpair
ex de, hl ; DE has address of int16: 3 ... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + ... FONTBASE
; restore DE ...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…
... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + FONTBASE ... /> ld (de), a
; negate hl
xor a
sub l
jr z, .closeparen
cp '''' ; SjASMPlus uses '' as escape code for ...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…
... /> add hl, hl
add hl, hl
add hl, hl ; HL = char * 8
add hl, de ; + FONTBASE ... /> ld (de), a
; negate hl
xor a
sub l
jr z, .closeparen
cp '''' ; SjASMPlus uses '' as escape code for ...How to get Grahics to wrap vertically around the screen?I am using the following code to draw an image to the screen. First I use HL to contain ROW and COLUM I then call the MapScreenFunction As I draw m…
... br /> ld a,h
sub 8
ld h,a ... hl,hl
ld de,scrtable
add hl,de
add a,(hl)
inc hl ...
ld h,(hl)
de)
or (hl)
ld (hl),a
inc ...Machine Code Sprites Example Code Using Char Based SystemBelow is my WIP code to do smooth screen wrapping sprites using char positions and offsets, as opposed to writing direct to a line (0-191) and shifti…
... LD A,(IX+3)
SUB (ix+7)
ld ... /> LD A,8
SUB (ix+7)
ld ( ... Z,l01
SUB (IX+6)
LD (IX ... br /> ps0:
ADD HL,DE
DJNZ ps0
...IM2 Machine Code Sprites Example Code Using Char Based SystemFurther to my earlier post, here are sprites running using char method with IM2 driving it Note, for 48k spectrum using TASM [code] ; ***********…
... LD A,(IX+3)
SUB (ix+7)
ld ... /> LD A,8
SUB (ix+7)
ld ( ... Z,l01
SUB (IX+6)
LD (IX ... br /> ps0:
ADD HL,DE
DJNZ ps0
...Smooth Color Masked Sprites using fast page flip on 48kHere is a quick demo of using char based sprites using the Page flip method: a) Background is copied to buffer b) Sprites drawn on buffer c) Buffer …
... SP
EX DE, HL
LD SP, HL
EX DE, HL
LD A,8
SUB E ; take it from 8 ...
ADD HL,DE ; Add onto GFX
EX DE,HL ; Let DE now point ...Smooth Masked Sprites using fast page flip on 48k Part 2Ok, After all the suggestions in Part 1, which were all excellent (Thankyou), I opted on the following: I have 2 x 6k Offscreen areas (Yes, that's …
... br /> LD A,8
SUB E ; take it from 8 ... br /> ADD HL,DE ; Add onto GFX
EX DE,HL ; Let DE now point ... br /> LD HL,0
LD DE,16
ADD HL,DE
LD ...Smooth Screen Scrolling RoutineHi everyone, this is a follow up to the thread on smooth screen scrolling. As promised here is the code for the routine. It's pretty long and fairl…
...
LD A,4
SUB B
ADD A,A ... />
LD A,5
SUB C
LD (COLMODA+1 ... ,CLOOPB
EX DE,HL ;DE = SCREEN ADDR.
ZERO ... in background data table
SUB 12
LD L,A ...Problem with rotating procedureHi folks! I wrote a proc in z80 asm, based on: x' = x * cos (z) - y * sin (z) y' = x * sin (z) + y * cos (z) I used a precalculated table of sin a…
... /> jr nc,fin21
add hl,de
adc a,0
;argumenty: hl i de
;wynik: hl i de
;============================================================================
... />
ld a,e
sub c
ld e,a ...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…
... if not line2 yet
sub a ;?? prepare blank byte ... into accum??
sbc hl,de ;move pointer of line to ... /> add hl, de ;to posn to be copied
ex de,hl ;?? but ... next line up
sub 7 ;next line up is ... next line up
sub 7 ;next line up is ...Probing the variables in 128K modeHello again! Briefly, I'm writing an m/c routine to read some BASIC variables. So, before I start, I try to get an idea for the structure of how var…
... Z,STRINGARRAY
SUB 128
LD DE,19
PRINT
ADD HL,DE
JR NEXTVAR
STRINGARRAY
SUB 96
LASTCHAR
SUB 128
JUMP
LD DE,6
JR ... PRINT
ARRAY
SUB 32
A fast DRAW routineI was investigating how to speed up the line drawing for the [URL="http://www.worldofspectrum.org/forums/showthread.php?t=20225"]BASIC compiler[/URL]…
...
exx
add hl, de ; error -= dX
... HL = error = DX / 2
; DE = -dY
xor a
sub ... br /> exx
add hl, de ; error -= dY
ld de, (SCREEN_ADDR)
add hl, de ;; Final screen ...
