-
Zynaps scrolling - anyone ever reverse enginnered this?Zynaps has IMO some impressive scrolling - it utilises 18 character rows of the display file, so quite a large active play area, and scrolls 2 pixels…
... ld (34273), sp ; 34250
xor a ; 34254
ld (34280 ... hl), c ; 34448
ld h, (ix+5) ; 34449
xor a ... ld a, (hl) ; 34477
xor b ; 34478
ld (hl ... ld a, (hl) ; 34513
xor 24 ; 34514
ld (hl ... -
Dynamite Dan II - Island 6 - HELP!Hi all, can someone possibly create a snapshot of Island 6 (car park island) on Dynamite Dan II for me please? I'm trying to work out why half the…
... $556 ; load CODE
xor a
out ($fe),a ... />
poker: ld c,8 ; Island 1
...
dec c ; Island 2
bit ...
dec c ; Island 3
bit ... 29384
ld (hl),c ; Write Island number into 29384 ... -
Tricks to make mirror image of a graphic?I've been working on a sprite routine for lots of sprites and animations. I'm only storing right facing graphics, and converting them to left facing.…
... 7
lp: xor a ; 4
ld c, (hl) ; 7 ...
b1: bit 1, c ; 8
jr z, ...
b2: bit 2, c ; 8
jr z, ...
b3: bit 3, c ; 8
jr z, ...
b4: bit 4, c ; 8
jr z, ... 7
b7: bit 7, c ; 8
jr z, ... -
Remainder (Mod) calculationsI've been figuring out how to calculate remainders after integer division by a constant divisor k (A mod k = A % k). I found that for most small di…
... ), same numbers used in your C code above, you can find ... -
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... /> ld (player_x), a
xor a ; a = 0
... /> ; c column
;
sprite8x8a:
; zero A
xor a ... :
; zero A
xor a
; convert y-coord ... :
; zero A
xor a
; convert y-coord ... -
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... /> ; c column
;
sprite8x8a:
; zero A
xor a ... :
; zero A
xor a
; convert y-coord ... :
; zero A
xor a
; convert y-coord ... :
; zero A
xor a
; convert row -> ... -
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
...
; c column
;
sprite8x8a:
; zero A
xor a ... col onto it
add c
ld l, a
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
...
; c column
;
sprite8x8a:
; zero A
xor a ... col onto it
add c
ld l, a
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... l = pixel y-coord
; c = pixel x-coord/8
; zero A
xor a
; convert row -> ... in cells at column C and C+1
ld ... in cells at column C and C+1
ld ... ld de, gfx16x16_ball
ld c, 5 ; column of screen< ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... not pixel coord)
; c = pixel x-coord/8
; zero A
xor a
; convert row -> ... col onto it
add c
ld l, a ... screen in cells at column C and C+1
ld ... in cells at column C and C+1
ld ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
...
; c column
;
sprite8x8a:
; zero A
xor a ...
; c column
;
sprite8x8aDoubleStride:
; zero A
xor a ... /> sprite8x8caAlwaysLookupRow:
; zero A
xor a
; convert y-coord ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... /> sprite8x8caAlwaysLookupRow:
; zero A
xor a
; convert y-coord ... screen in cells at column C and C+1
; Unrolled loop ... screen in cells at column C and C+1
ld a ... screen in cells at column C and C+1
; Unrolled ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
...
; c column
;
sprite8x8aDoubleStride:
; zero A
xor a ... column C and C+1
; Unrolled loop, 7 iterations
xor a ...
add c
ld l, a
xor a
; unroll ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... x coord of exit
xor a
ld (level_exit_y), a ... /> ld hl, player_xprev
ld c, (hl)
ld hl, player_yprev ... /> ld hl, player_x
ld c, (hl)
ld hl, player_y ... br /> ; B -> row
; C -> column
; A -> ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... x coord of exit
xor a
ld (level_exit_y), a ... /> ld hl, player_xprev
ld c, (hl)
ld hl, player_yprev ... /> ld hl, player_x
ld c, (hl)
ld hl, player_y ... br /> ; B -> row
; C -> column
; A -> ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... ld (23693),a
xor a
call 8859< ... /> ; B -> row
; C -> column
; A -> ... /> ; B -> row
; C -> column
; A -> ... ; B -> row
; C -> column
; A -> ... loop counter
dec c
jr nz, ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... +3)) and the column in C (was previously passed in (IX ... , HL and B. Looks like C is unchanged. DE will be ...
; c column
;
sprite8x8a:
; zero A
xor a ... col onto it
add c
ld l, a
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... +3)) and the column in C (was previously passed in (IX ... , HL and B. Looks like C is unchanged. DE will be ...
; c column
;
sprite8x8a:
; zero A
xor a ... col onto it
add c
ld l, a
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…
... sprite16x16ca:
; zero A
xor a
; convert row -> ... sprite16x16caXOR:
; zero A
xor a
; convert row -> ... column C and C+1
ld a, (de)
xor (hl ... column C and C+1
ld a, (de)
xor (hl ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
...
; c column
;
sprite8x8aDoubleStride:
; zero A
xor a ... column C and C+1
; Unrolled loop, 7 iterations
xor a ...
add c
ld l, a
xor a
; unroll ...How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... that). If you have B, C, D, E, H or L ... unchanged and clears carry flag, XOR A sets A to zero ...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…
... sprite16x16caOR:
; zero A
xor a
; convert row -> ... sprite16x16caXOR:
; zero A
xor a
; convert row -> ... column C and C+1
ld a, (de)
xor (hl ... column C and C+1
ld a, (de)
xor (hl ...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…
... here
rr c
djnz .shiftagain
xor (hl)
... /> ret z
ld a, c
xor (hl)
ld (hl ... rla
rl c
djnz .shiftagain
xor (hl)
ld ... /> ret z
ld a, c
xor (hl)
ld (hl ...
