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Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... HASH LD HL,MainScreen ; screen address
LD B, ... ; put back to the screen
INC HL ; ... ;start of screen file
ld bc,$18 ;0 ... into B; 8 pixel rows x 3 screen ... -
Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... registers
push bc ; Store BC registers
... ATTR_ROW_CHAR
pop bc ; Restore BC registers
pop hl ; Restore ...Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... registers
push bc ; Store BC registers
... ATTR_ROW_CHAR
pop bc ; Restore BC registers
pop hl ; Restore ...A Neat Redefine Keys RoutinePreviously, I’ve only shared this routine with a couple of people via PM, but I’ve now decided to make it public. I optimized it for size, so it uses…
... ,2
CALL CHAN_OPEN
POP HL
CALL PRINT
PUSH BC
LD B,10 ; 0 ... /> HALT
DJNZ DELAY
POP BC
RET
PRINT ...Loadsa bullets on screen (silkworm)Did games like silkworm just draw everything to the screen or did they have complicated optimisations? and the types of games where sprites can occu…
... just draw everything to the screen or did they have ... br /> Sikworm draws everything to buffer in this order: background ( ... is drawn, LDI copy moves screen buffer to screen. The scrolling belt at ... ground is redrawed directly in screen, it is not part of buffer.Other than using attributes what other ways to detect collisions, when using char based movement?So I'm slowly working out the bits and pieces to write a game completely in assembly. I've been using attributes when writing in BASIC to detect whet…
... BC and PUSH HL at the start of the routine, then POP ... HL and POP BC at the end so ... them in registers) is first POP the return address off the ... not using (e.g. POP IX) then PUSH the numbers ... . Just be sure to POP the right number of values ...ive found an attr scrolling routine but i want to remove the smaller scroller within it, etc.https://pastebin.com/K4nG3xbX also i would like to be able to change the colours and not have a shadow. http://www.worldofspectrum.org/pub/sin…
... ; FA6B 23
POP BC ; FA6C C1
... ; FB2C 23
POP BC ; FB2D C1
... (+32 bytes)
POP BC ; FB65 C1
...ive found an attr scrolling routine but i want to remove the smaller scroller within it, etc.https://pastebin.com/K4nG3xbX also i would like to be able to change the colours and not have a shadow. http://www.worldofspectrum.org/pub/sin…
... row (+32 bytes)
POP BC ; FB65 C1
DJNZ ...
L_FAF5: PUSH BC ; >1 BC=counters
PUSH DE ... FB01 C2 FE FA
POP BC ; 3 DE=attributes address< ...Other than using attributes what other ways to detect collisions, when using char based movement?So I'm slowly working out the bits and pieces to write a game completely in assembly. I've been using attributes when writing in BASIC to detect whet…
... same time with an LD BC,(nnnn) instruction. Just remember the ... then Y, when you LD BC,(nnnn) then X ends up ... . I could PUSH BC at the start and POP BC at the end ...Proportional-width fontsFor reasons that are still not quite clear to me (because I’ve always loved typography and design,) I never bothered to write a proportional-font rou…
It might be easier in cases like that to render to a slightly larger off screen buffer and then do the flipping as a separate step. It may also help with scrolling text, since you potentially can skip over re-rendering all the text each time.Proportional-width fontsFor reasons that are still not quite clear to me (because I’ve always loved typography and design,) I never bothered to write a proportional-font rou…
... to a slightly larger off screen buffer and then do the [b ...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…
... /> CALL 7828
POP HL
POP BC
LD (HL), ... CALL 8933
POP HL
POP BC
INC C< ... JR NZ, 30125
POP BC
DEC B
... JR NZ, 30121
POP DE
POP BC
LD A, ( ... (IY+92), C
POP BC
LD A, B
Maze Death Rally-XJust released a demo of my new game which I'm developing for this years ZXDev MIA & Remakes compo. The game is a remake of the classic Spectrum & ZX8…
Thanks for the great feedback :-) and just found the bug Mat, a stray pop bc causing the return to fail in a catastrophic way! Just sent you a new test version. Very impressed how you find theseGyroscope - reverse engineering the 3 title theme tunesHello, Does anyone know if anyone has done any disassembly work on Gyroscope? I'm particularly looking to get the three title tracks back into a …
... /> push de
push bc
push ix
... ; copy destination
ld bc,#0005 ; copy 5 bytes
lc4ac: pop ix
pop bc
pop de
pop hl
ei ... ret
lc4eb: pop hl
pop hl
ret
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
This driver use incorrect reading of mouse button port. Need small fix.
mouse_btn LD BC, 64223
IN A, (C)
OR 252
CP 255
JR NZ, end_pointer
POP BC
RETHow about a Widescreen hack?After taking a look at manic miner 'scroller and width' hacks it just struck me.. Would it be possible to make a game (or convert a previously rel…
... -column mode as a single screen rather than two halves. You ... get 255 pixels from one screen buffer and 145 from the other ...Drawing LinesHas anyone got any experience of coding a Bresenham line drawing algorithm on the Speccy? I've had a go and I find the algorithm has quite a few s…
... ;
DRAWBRESLINE LD (DBLSTART),BC
LD (DBLEND),DE< ... br /> DBLDLP1 PUSH BC
LD BC,(DBLXVAR)
... = y + yinc2
DBLDEND POP BC
DJNZ DBLDLP1
;
DBLPLOTSUB LD (COORDS),BC ; Based on ROM routine at ...Drawing LinesHas anyone got any experience of coding a Bresenham line drawing algorithm on the Speccy? I've had a go and I find the algorithm has quite a few s…
... copy up my 2/3 screen buffer, plus more time to erase ... the old buffer. So this is running pretty ...Drawing LinesHas anyone got any experience of coding a Bresenham line drawing algorithm on the Speccy? I've had a go and I find the algorithm has quite a few s…
... it to use a columnular screen buffer.
[b]Lethargeek[/b] - the ... screen clear followed by the copy ... for the bottom of the screen - now to do the other ...im looking for other games like the muncher that use double height and width graphics with colouri havent come across this type of graphics mode on the spectrum before and would like to know if there are any other games that use it.
...
shuffle_sprite:
push bc
ld a, (ix+2 ... br /> ld b, h ; BC = sprite length
ld ... inc hl
dec bc
ld a, c ... /> add ix, de
pop bc
djnz shuffle_sprite
...im looking for other games like the muncher that use double height and width graphics with colouri havent come across this type of graphics mode on the spectrum before and would like to know if there are any other games that use it.
...
line_mirror_loop:
push bc
ld hl, (keep_spr_width ... /> djnz col_mirror_loop
pop de
pop bc
djnz line_mirror_loop
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 bc,($5C3D)
push bc ; save original ERR_SP
ld bc,return
push bc
ld ($5C3D ... />
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…
... ; CH_ADD
ld bc,($5C3D)
push bc ; save original ERR_SP
ld bc,return
push bc
ld ($5C3D ... />
exitgoto:
pop bc
ld ($5C3D),bc ; restore orginal ERR_SP
Spectrum games that are both 48k and 128k but where the 128k version is infinitely superior The only one I can think of is "Rock Star Ate My Hamster" but there must be others . So where are the games where the 128 version is great but wher…
... games render to an off-screen buffer, but the 48K version has ...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…
... a single byte.
POP BC = 10 T states
When you execute a POP BC, the following happens
When you POP BC, C = first byte of ... 39 XXXXXXXX
Each POP BC advances the stack pointer 2 ...Smallest playfield game?What is the game with the smallest playfield? I'm not referring to map size, but where the action takes place. Some examples: - Jet Pac: The acti…
... to draw to an off-screen buffer and copy the whole thing ... to redraw the entire game screen between passes of the TV ...
