-
Screen LoaderCouple days ago i find very interesting loader routine in ex Yugoslavia magazine "Svet Kompjutera" from january 1987. Authors of article, calls this …
... /> RET NC
LD A,C
XOR &03
LD ... C,A
LD H,& ... LFF41
LFF32 RL C
XOR L
RET NZ< ... br /> LD A,C
RRA< ... amp;FE)
RRA
XOR C
AND &20
Kiwi OS for z80 computerHi everyone, Nearly made my z80 computer with 2K ROM 32K RAM. It has an OS im still writing called Kiwi (apple, blackberry, you get the idea ;D) he…
... CURRENT DATA VALUE)
XOR C ;XOR THE CURRENT VALUE (TOGGLE ... CURRENT DATA VALUE)
XOR C ;XOR THE CURRENT VALUE (TOGGLE ... CURRENT DATA VALUE)
XOR C ;XOR THE CURRENT VALUE (TOGGLE ... DATA VALUE)
XOR C ;XOR THE CURRENT VALUE (TOGGLE ...checksum routine from Space GunThis routine starts off with HL=$ffff and a file header read from tape, for each byte of which in turn it assigns to A and calls this routine, ending…
... .
[code]
LD C,A : XOR H : AND $f0 :
LD ... :
LD B,A : RRA : XOR H : AND $0f :
LD ... : LD A,E : XOR C : AND $0f :
LD C,A : RLA : RLA ... ,A : LD A,B : XOR H : XOR E
LD H,A ... : LD A,B : RLA : XOR D : OR C
LD L,A ...Adding a pause key to ArkanoidHaving rediscovered the simple pleasure of playing 1980s games on genuine 1980s hardware, I've also remembered that emulation can provide a feature m…
... (bit 0)
in a,(c) ; read it
rra ...
rra
jr c,$ - 3 ; keep probing until ... ,(0xfe)
rra
xor c
and 0x20
...Movin And A Groovin Horizontal Flip improvementOn the left is the flip horizontal portion from Andy Pennell'S excellent Movin' & a Groovin' machine code screen routines from Your Spectrum #19 (Oct…
... br /> xor c
and %01100110
xor c ;a=GFEDCBAH ... br /> xor c
and %01100110
xor c ;a=GFEDCBAH ...RCS HelpThis plea for HELP is related to the RCS screen handling routines thread. To further save space in the current crop of routines its looking like the …
... /> A9 lp1 xor c
E6F8 and $f8
A9 xor c
57 ... ld d,a
A8 xor b
A9 xor c ...Ghosts n' Goblins loaderI'm trying to put Ghosts n' Goblins onto a +3 disk but struggling to understand the mc loader. Basic loader [code] ink 7 : clear 25000 : load "" cod…
...
65140: RL C
65142: XOR L
65143: RET ...
65205: NOP
65206: XOR C
65207: AND 32
65385: RL C
65387: XOR L
65388: RET ...
65460: NOP
65461: XOR C
65462: AND 32
Unusual custom turbo loaders - with sourcesI have always been fascinated by turbo loaders; my games all feature a TZX version with one of such schemes implemented, and I have been experimentin…
... /> LD A,C
XOR 003
LD C,A
... JR 65451
RL C
XOR L
RET NZ< ... A,(254)
RRA
XOR C
AND 032
... /> LD A, C
XOR 3
LD C, A
... , (254)
RRA
XOR C
AND 32
JR ...A sped up pixel-shift routine for 1-byte–wide spritesHere’s an optimized (for speed) real-time sprite shifting routine for sprites that are one byte wide. It uses no memory variables for storage of inte…
... counter
ld c,(hl) ;load C with first byte
xor a ;clear A and ... br /> msl_shift
rr c ;shift through Carry
... into A
xor c ;merge it with C
ld ( ... /> ld a,(hl)
xor b
ld (hl), ...Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... putc:
xor a
or c
ret z ...
.toomanylines
xor a
inc a
.only1halflinepressed
xor a ; zero A
... /> .onlysymshiftpressed
inc c
xor a
ret
line routineWondered if anyone can help me out. I have been programming a 3d graphics library for the spectrum, in Machine code. The line routine that I have i…
... A,L ; old x
XOR C ; new x
AND 8 ... on screen
ADD A,C
SUB L
LD ...line routineWondered if anyone can help me out. I have been programming a 3d graphics library for the spectrum, in Machine code. The line routine that I have i…
;
; Graph Library
; (c) SerzhSoft '03.10.96
; ... /> ld e,a
jr c,$+6 ;->
ld a ...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 …
... ld a,b
or c
ret z ; if ... /> cp h
jr c, swap3
jr nz, ... qsort1
ld a,c
cp l
... HL aligns on item
xor c
rra
jr ... last+1
ld l,c
ld h,b
Loading schemes18 years ago I hated loading schemes like Alcatraz and Speedlock because they were a b*tch to copy and became unreliable when the tape got older. Now…
...
ld a,c
xor $03
ld c,a
ld ... lff41
lff32 rl c
xor l
ret nz
rra
xor c
and $20
jr ...In Machine Code, what is the quickest way to sort bytes?I am playing around with some ordering of sprites, where I want to order them by vertical position. I used some Rodnay Zaks code to order some bytes…
... value to swap
ld c, 123 ; 2nd value to ... 1st value into a
xor c ; merge with 2nd value< ... result in 1st value
xor c ; restore to 1st value< ... merged 1st/2nd values
xor c ; remove 1st value
...How does interrupts work?I am a little confused regarding the interrupts on the Spectrum. If I have some hundred bytes of machine code started with, say, [B]RANDOMIZE USR 300…
... /> 168 xor b
169 xor c
170 xor d
171 xor e ...
172 xor h ...
174 xor l
175 xor (hl)
176 xor a
Splitting Images tzx maybe not perfectI've been hacking this game and its loader. Also the save routine is intact in this game. It saves a block with a pilot length of 801 pulses. Test…
... /> ld sp, $abf4
xor a
out ($fe), a ... br /> ld a, c
xor $03
ld c, a
... l_a1fb
l_a1ec: rl c
xor l
ret nz ...
ld a, c
... , ($fe)
rra
xor c
and $20
jr ...DarkStar.tzx in Spectaculator 6.25Hi all I think I have found a bug in Spectaculator. Darkstar.tzx(OriginalRelease) wiil not not load. DarkStar.tap loads The DarkStar Re-release t…
... actual data.
The C register holds the current value ... clears the EAR bit in C. This is okay if it ... 1F RRA
FD2F A9 XOR C ; DOH!
FD30 E6 20 ... [/code]to avoid messing with C altogether.
[quote=Jon ...Jetpac questionHi all, I just bought a copy of Jetpac off of Ebay and I'm having problems. To start, I'm trying to play it on an issue 2 Speccy with Interface 1, 2 …
... SaveRamtopValue
Detected_48K
XOR A ; Set 48K RAMTOP value ... /> ;Store end of scan in C (C is preserved by the RAND16 ...
LD A,B
XOR C
LD (FailedBits),A
PUSH BC
LD C,D ; Load (C)orrect byte and (B ...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…
... a,(hl)
xor c
ld (hl),c ;hl, the screen address ... a,(hl)
xor c
ld (hl),c ;put graphic in there ... a,(hl)
xor c
ld (hl),c ;hl, the screen address ... a,(hl)
xor c
ld (hl),c ;put graphic in there ...Serial protocol, help!Hi, simply trying to find best way to transfer programs from PC to real ZX Spectrum for testing purposes. Under Windows I tried using Spxfr and it w…
... states
rr c ; and to msb (c) |8 t-states ... states
rr c ; and to msb (c) |8 t- ... />
stop_bit:
;; invert c to get real value to ... | 7 t-states
xor c ; 0xff xor anything = !anything | 4 t ...RFC: 64 column font codeIn BASIC, type CLEAR 49999 then import the code at 50000. Then type RANDOMIZE USR 50000. This will create a new channel and attach stream #4 to it. A…
... code accordingly
xor c ; compare BIT 0 from character ... accordingly
srl c ; check BIT 0 from current ... font data)
xor a ; first font byte is ...RFC: 64 column font codeIn BASIC, type CLEAR 49999 then import the code at 50000. Then type RANDOMIZE USR 50000. This will create a new channel and attach stream #4 to it. A…
... code accordingly
xor c ; compare BIT 0 from character ... accordingly
srl c ; check BIT 0 from current ... font data)
xor a ; first font byte is ...RFC: 64 column font codeIn BASIC, type CLEAR 49999 then import the code at 50000. Then type RANDOMIZE USR 50000. This will create a new channel and attach stream #4 to it. A…
... code accordingly
xor c ; compare BIT 0 from character ... accordingly
srl c ; check BIT 0 from current ... font data)
xor a ; first font byte is ...RFC: 64 column font codeIn BASIC, type CLEAR 49999 then import the code at 50000. Then type RANDOMIZE USR 50000. This will create a new channel and attach stream #4 to it. A…
... ; call DRIVER
; ret c ; stop if row changed (reached ... accordingly
xor c ; compare BIT 0 from character ... data)
xor a ; first font byte is ...Kobrahsoft DB1 - doesn't work?Hi, I've tried loading [URL="http://www.worldofspectrum.org/infoseek.cgi?regexp=^DB1$&pub=^Kobrahsoft$&loadpics=3"]DB1 by Kobrahsoft[/URL] into two …
...
XOR E ; 8004 AB
XOR D ; 8005 AA
XOR C ; 8006 ... A9
XOR B ; 8007 A8
Need help with tzxingI recently got a copy of this Polish text game: [url]http://www.worldofspectrum.org/infoseekid.cgi?id=0006622[/url] I can't make a tzx of it howeve…
...
LD C,E
EXX
XOR A
... CP 15
JR C,L49465
XOR A
DEC A ... RRA
RET NC
XOR C
AND 32
JR ... br /> SUB H
XOR 1
PUSH HL
LD H,A
XOR 192
DEC A
Need help with tzxingI recently got a copy of this Polish text game: [url]http://www.worldofspectrum.org/infoseekid.cgi?id=0006622[/url] I can't make a tzx of it howeve…
... D0 C1A0-63F3=23981
XOR C ; C1A1 A9
AND ... 28 F3
LD A, C ; C1A6 79
CPL ... ; C1A7 2F
LD C, A ; C1A8 4F
...
