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Machine code issue...Hi Folks, My trials with MCODE continue and I am stuck. I wrote the following program in BASIC to simply POKE an attribute byte in to a "box" on th…
... ATTR Address
09 ADD HL,BC ;HL=HL ... /> 23 INC HL ;Add 1 to Address
... LD DE,32
19 ADD HL,DE ;Add 32 to Address< ... DE=Width
C600 ADD A,0 ;Reset Carry< ... -
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…
... hl=char to plot
add hl,hl ; 11t - x2< ... br /> add hl,hl ; 11t - x4
add hl,hl ; ... font mem location ($3C00)
add hl,bc ; 11t - move ... convert to screen address
add a,l ; 4t
ld ... ,l ; 4t
add a,32 ; 7t - add 32 or one char down ... -
display file addressing; screen slicingWhile working on this Compendium I'm updating or rewriting a lot of stuff. One thing I eventually came to appreciate was the simple & clever way in w…
... each line of pixels has 32 column bytes.
To ... /> To move down the rows add 32 to L.
To move ... down the segments add 8 to H.
To ... segment*8
L = charrow*32
HL= H*256 + L ... version posted here uses fixed 32 byte blocks so the ... -
Collision detection for interlocking shapes[SIZE=3][FONT=Calibri]I?m looking for some advice as I?m not sure how to resolve the following problem. I have an in memory structure that holds info…
... ]
[SIZE=3][FONT=Calibri]32 ; Add 32 to the starting address (so ... ]
[SIZE=3][FONT=Calibri]32 ; Add 32 to the item drawn previously ... /> [SIZE=3][FONT=Calibri]1; Add 1 to the item drawn ... -
Double-Buffer ScreenFor my Alien Breed Speccy re-write I decided to use a Double Buffer (DB) or 'Back Screen' to draw all the game action onto, before shuffling the whol…
... loop1:
ld bc,32 ;BC is counter for block ... slice
ld a,32 ;A litle loop to dec ... inc d ;Inc d to add 256 to de
... again
ld a, 32 ;Add 32 to e, by using a ... reg
add a,e
ld ... -
Problem with BC corrupting after DJNZJust for fun, I'm messing around trying to get the level maps from Lemmings to display on the screen with machine code. It's been ages since I did an…
... screen I have to add 32 to the map address ... HL,50213 ; MAP START ADD
LD DE,16384 ... ; SCREEN START ADD
LOOP1 ... THE SCREEN, 32 CHARS
INC E ; ADD 256 TO ... 32 ; 32 TO ADD TO THE MAP ADDRESS
ADD HL,BC ; ADD 32 ... -
How would you approach parallax?So ... there is this trick by Joffa that we all know...of waiting for the ULA to reach certain pattern on the screen using the IN command. And then s…
... tiles? If your screen is 32 tiles x 16 tiles (top ... you're done you'd add 32 to the original value to ... -
A sped up pixel-shift routine for 1-byte–wide spritesHere’s an optimized (for speed) real-time sprite shifting routine for sprites that are one byte wide. It uses no memory variables for storage of inte…
... A with L
add a,32 ;add 32 to it
ld l ...
jr c,msl_shift_done ;if ADD A,$20 results in overflow ... -
z88dk Spectrum Screen Driver problemHi guys, I've been messing around with z88dk a bit and was trying to output some stuff to the screen. Reading the docs, it says that I can use the Z…
Okay, I answered my own question - for some reason I need to double my x coordinate before I add 32 to it. Anyone know why? :)
Solution:
int chars = sprintf(output, "\x16%c%c%s", (char)(y+32), (char)((x*2)+32), str); -
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…
... with one byte
and add a LF in begin. (NOTE ... to lower 33 Bytes and add
32 Spaces and a #76 ...
LD C,L
ADD HL,DE
EX DE ... -
Help needed to speed up functionCan anyone help me to re-factor this code snippet. The "MAP" section holds information about which tiles go where on the screen (handled by another f…
... ;+ 11
LD DE,32 ;+ 10
ADD HL,DE ;+ 15
LD A,32 ;+ 7
ADD A,L ;+ 4 Add 32 to Low part ...
ADC A,H ;+ 4 Add carry out to High part ... -
Help needed to speed up functionCan anyone help me to re-factor this code snippet. The "MAP" section holds information about which tiles go where on the screen (handled by another f…
... /> SET 5,L ; in fact Add 32
LD (HL),A
DEC L ; you added 32
LD (HL),A
LD DE,32
ADD HL,DE
... -
Help needed to speed up functionCan anyone help me to re-factor this code snippet. The "MAP" section holds information about which tiles go where on the screen (handled by another f…
... is low and when you add 32 you just set bit 5 ... -
z88dkHello. I'm an spanish user of spectrum (and naturaly of this page). I have a question. I want to start to program games with z88dk, but I need a goo…
z88dkHello. I'm an spanish user of spectrum (and naturaly of this page). I have a question. I want to start to program games with z88dk, but I need a goo…
... is because you need to add 32 to desired screen location
You need to add 32 before you convert to hex ... is because you need to add 32 to desired screen locationz88dkHello. I'm an spanish user of spectrum (and naturaly of this page). I have a question. I want to start to program games with z88dk, but I need a goo…
... is because you need to add 32 to desired screen location
Edit: Forgot to add that z88dk puts you in ... default. You'll have to add a printf("\x01\x20"); at ... the beginning to switch to 32 column mode.Reason for strange display layout?I have always wondered if there is any technical reason behind the strange layout of the display file or why did Sinclair choose to do it this way?
... character you'd have to add 32 when moving down scan lines ...Reason for strange display layout?I have always wondered if there is any technical reason behind the strange layout of the display file or why did Sinclair choose to do it this way?
... character you'd have to add 32 when moving down scan lines ... a massive saving over adding 32! I suppose the character drawing ... drawing loops just need an ADD HL,DE to advance lines ... , with DE holding 32 throughout. Unrolling the drawing loops ...Changing the way SCREEN$ is loadedThe way the speccy loads in a SCREEN$ is interesting - top two-thirds first, then middle and finally the bottom, which is due to the way the speccy d…
... counter
startline: ld c, 32 ; c = byte counter
drawline ... /> jr nz, drawline ; continue if 32
dec b ; 1 ... -byte of screen address
add a, 32 ; add 32
ld (screenaddress+1 ...Fastest Block Drawing Code?Following on from my scrolling thread [URL="http://www.worldofspectrum.org/forums/showthread.php?p=351304#post351304"](http://www.worldofspectrum.org…
... .e. the end of one 32 byte (or bigger/smaller) line ... straight into the next, just add 32 (or whatever) to get to ...Recent talk of developing new SpectrumsHi all, I can see from a few threads on here that some Wossers like Vasil and Aien 8 are interested in developing more powerful Spectrums or improvi…
... , you will have to add 32 every row (ADD HL,rr) instead of ...Recent talk of developing new SpectrumsHi all, I can see from a few threads on here that some Wossers like Vasil and Aien 8 are interested in developing more powerful Spectrums or improvi…
... , you will have to add 32 every row (ADD HL,rr) instead of ... /> ld a,l
add a,32
ld l,a
Recent talk of developing new SpectrumsHi all, I can see from a few threads on here that some Wossers like Vasil and Aien 8 are interested in developing more powerful Spectrums or improvi…
... /> [CODE]
ld a,32
add l
ld l,a ...
ld a,l
add 32
ld l,a
ld a,l
add 32
ld l,a
[CODE]
ld de, 32
add hl,de
[/CODE]
...
ld a,l
add 32
ld l,a
Calculating the address of a pixel?Hi Folks, Is there an easy/quick way of calculating the memory address of a pixel? So for example, if I wanted to "plot" pixel at screen coordinate…
... move to the next character. Add 32 and you move to the ...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…
... hl=char to plot
add hl,hl ; 11t - x2< ... br /> add hl,hl ; 11t - x4
add hl,hl ; ... font mem location ($3C00)
add hl,bc ; 11t - move ... convert to screen address
add a,l ; 4t
ld ... ,l ; 4t
add a,32 ; 7t - add 32 or one char down ...Using ATTR detection in machine codeIs there a ROM routine that can be called that reads the ATTR value of a co-ordinate?
... across each row
add a,l ;add xcord to low byte ... /> loop ld de,32 ;each row is 32 bytes apart, need to ... , hence 'de'
add hl,de ;so add 32 the same no of ...Using ATTR detection in machine codeIs there a ROM routine that can be called that reads the ATTR value of a co-ordinate?
... a loop to multiply by 32.
[/QUOTE]
add 32 was a bit rubbish, I ... /> (By the way daveysludge, the add a,l is unnecessary just ...Display file addressHi Folks, Could someone please help me. I seem to recall that the address of a given byte of the Spectrum's display file breaks down as row, column…
... />
Cc character column 0-32
Cr character row 0 ... /> [code]10 LET address = Cc + 32 * Cr + 256 * L + 2048 * T ... : to go down one third add 2048. To go to the ... next char, add 1. To go to the next character line, add 32.Machine Code Routine of the weekHow about a thread that has a routine each week that is in [B]assembly language[/B] and is also described in great detail what the hell is going on …
... of INC HL/DEC HL/ADD 32/SUB 32.
[ ... ADD HL,HL ADD HL,HL
ADD HL,HL ADD HL,HL
ADD ... HL,HL ADD ... HL=char*8
ADD HL,DE ADD HL,DE ; HL=& ... LD A,H
ADD A,8
LD H ...Machine Code Routine of the weekHow about a thread that has a routine each week that is in [B]assembly language[/B] and is also described in great detail what the hell is going on …
... of INC HL/DEC HL/ADD 32/SUB 32.
[code]; Print ... /> ADD HL,HL ADD HL,HL
ADD HL,HL ADD HL,HL
ADD ... HL,HL ADD ... /> ADD HL,HL
ADD HL,HL
ADD HL,HL
ADD HL ...
