-
How to print logo onto screen at chosen coordinates?Hi, I've just got back into zx spectrum games after all these years and after seeing some of the great games on here I would like to start learning p…
... clear the screen
loadfont:
ld hl,(23606) ;load HL with value ... string
; ld bc,6 ;BC contains string length
ld de,dat ; ... br /> pop hl ;recover value from the stack
ld (23606),hl ;restore ... -
How to print logo onto screen at chosen coordinates?Hi, I've just got back into zx spectrum games after all these years and after seeing some of the great games on here I would like to start learning p…
... />
ld a,2
call 5633 ;open channel to screen (top ... 22 lines)
ld de,dat ; address of string
ld bc ... ] **
pop hl ;recover value from the stack
ld (23606),hl ;restore original ... reached the bottom of the screen? -
How to print logo onto screen at chosen coordinates?Hi, I've just got back into zx spectrum games after all these years and after seeing some of the great games on here I would like to start learning p…
... screen (top 22 lines)
ld de,dat ; address of string
ld bc ... ] **
pop hl ;recover value from the stack
ld (23606),hl ;restore original ... reached the bottom of the screen?[/QUOTE]
I think defb ... -
Animated attribute revealA new challenge to solve next. I would like to create an animated attribute reveal in machine code by having my 768 byte attributes held in ram whic…
... sub-routines to disassemble a screen into random bytes and ( ... br /> ld hl,$4000
ld a,$23 ;A =INC HL
ld (INCDEC), ...
pop bc
dec bc
ld a,b
or ... -
Animated attribute revealA new challenge to solve next. I would like to create an animated attribute reveal in machine code by having my 768 byte attributes held in ram whic…
... (hl) ;increment screen INK directly
INK_OK: ld bc,(CHANGED)
inc bc
ld (CHANGED),bc ... :
pop de
SKIPDE: pop bc
dec bc
ld a,b ... -
Pac-Land: can be coloured?All versions of this game are full coloured, but not the Spectrum version. It has large sprites, but maybe the scroll is too fine to make a coloured …
... bottom screen black
EX AF,AF'
LD HL,23296 ;tile buffer, tile ... /> LD HL,23296 ;fill buffer with empty spaces
LD DE,23297
LD BC,639 ...
LD (HL),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 …
... br /> ld sp,bomberdata ; bomber graphic loc
ld hl,$4810 ; screen coordinates equivalent ... of 10th line on screen display
pop de ; load bomber ... of 16th line on screen display
pop de ; load ... -
Using the stack to blit bufferI was using a ldir to blit my back buffer to the screen RAM, and it was working pretty well if not rather slow. After reading about using the stack …
... ld sp,0
pop hl
pop de
pop bc
pop af
exx
pop hl ...
pop de
pop bc
cred_adr_2 ld sp ... -
Tile routinesHi all, Please does anyone have any examples of tile routines in pure asm to set up maptile screens. I would like to try and understand them and ti…
...
print_tile:
ld bc,(tile_x) ; loads C with column ... x8 pixel lines
; ld bc,(tile_x) ; retrieve co-ordinates
HL and POP HL. This saves the screen location so that ... -
Tile routinesHi all, Please does anyone have any examples of tile routines in pure asm to set up maptile screens. I would like to try and understand them and ti…
...
ld bc,0
ld (tile_x),bc ; start at top left of screen
pop bc ; retrieve BC
call get_screen_attr
ld a,(de)
ld (hl),a ... -
Tile routinesHi all, Please does anyone have any examples of tile routines in pure asm to set up maptile screens. I would like to try and understand them and ti…
...
ld bc,0
ld (tile_x),bc ; start at top left of screen
pop bc ; retrieve BC
call get_screen_attr
ld a,(de)
ld (hl),a ... -
New bicolour game coming very soon.And they say budget software houses can't afford to advertise :-D [IMG]http://i1142.photobucket.com/albums/n608/daveyboyhughes/elstompo_advertsmall_…
... timing (it runs faster during screen render), but it's not ... /> LD SP,$5822+ROWREPT*32+19 ; reference columns 19 and 20
LD HL ... ; columns 17 and 18 (*)
LD BC,nn ; columns 19 and 20 ... -
Interface 1bis updateSupport for connecting a standard PC keyboard to the interface?s PS/2 socket, in place of a mouse, has been added. The external keyboard?s output is …
... PB_CLR EQU #83; Discard buffer contents
;
... LD HL,#02B0; Change the return
3894 : e3 EX (SP),HL ... 38c0 : f1 NO_BRK POP AF; External keyboard
Interface 1bis updateSupport for connecting a standard PC keyboard to the interface?s PS/2 socket, in place of a mouse, has been added. The external keyboard?s output is …
... PB_CLR EQU #83; Discard buffer contents
;
... br /> 0071 : f1 POP AF
0072 : ... LD HL,#02B0; Change the return
388e : e3 EX (SP),HL ...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…
... your screen buffer is in linear order instead of Spectrum screen order? ... your data. Do POP to suck up data ... time using AF, BC, DE and HL (8 bytes) and ... br />
Remember POP moves the stack pointer minus ... don't forget this buffer screen can be bigger than ...Fuller AY only gamesThe definitive list: 1) Demonstration Tape 2) Bodysnatchas 3) Star Bike
... /> ;set stack and cls
ld sp,$8100
call $0d6b
hl
ld (hl),$00
inc hl
ld (hl),$98
inc hl
ld (hl),a ...
ld bc,$bffd
ld a,(hl)
out (c),a
pop bc
30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
... entire screen:
[CODE]LD IX,nn
LD IY,nn
LD BC ...
LD HL,nn
PUSH HL ; columns 6 and 7
LD SP,nn ... ; reference columns 28 and 29
LD BC,nn
LD DE ...30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
... /> ELSE
LD A,(HL) ; extra delay
LD (nn),HL ; update columns 0 ... /> PUSH HL ; update columns 6 and 7 on screen
LD SP,nn ; reference ... columns 28 and 29
LD BC,nn ...AMX mouse emulationI'm trying to add AMX mouse emulation to Spud but not getting very far. I can get a reaction to button presses but nothing to moving the mouse. …
... br /> 82ec e5 push hl
82ed 21c180 ld hl,80c1h
82f0 ... pop hl
82fc d1 pop de
82fd c1 pop bc
82fe f1 pop ... the ULA is drawing the screen.
Spectaculator's implementation ...AMX mouse emulationI'm trying to add AMX mouse emulation to Spud but not getting very far. I can get a reaction to button presses but nothing to moving the mouse. …
... br /> 82ec e5 push hl
82ed 21c180 ld hl,80c1h
82f0 ... pop hl
82fc d1 pop de
82fd c1 pop bc
82fe f1 pop ... the ULA is drawing the screen.
Spectaculator's implementation ...Optimal shifting for set pixel?Hi, I'm optimizing my set pixel code. For speed. But without using partitioned memory (i.e. a table on 256 byte boundary) I have optimal memory addr…
... is used to calculate display buffer memory offset, it's going ... HL,BC:LD H,HIGH PLOTTBL,L,D,B,(HL):INC H
LD A,(HL ... (HL)
INC H:LD C,A,A,(BC)
OR (HL):LD (BC),A
POP BC,HL ...Block RoutineHi Folks, I want to draw a block on the screen dependent on providing the X,Y,W,H values. I came up with the following: [CODE]100 LET l$=" …
Here's a much neater version of my previous post. Using IX for addressing the parameters simplifies the assembler code. The original routine needed all its parameters to be correct beforehand, as it was only doing a check on y, whereas all of x, y, x+w, y+ ...llvm-z80 statusFew months ago I read about efforts to produce llvm back-end for the Z80 (even perhaps as part of new z88dk). Any update on that? I found [URL="htt…
... , sp
ld sp, ix
ld hl, b
inc hl
ld b, (hl)
ld a ... /> ld (hl), b
ld a, c
ld (c), a
ld hl, 0
pop bc ...BIFROST* ENGINE 1.2 released!Another improved version of the BIFROST* ENGINE is now available! Download it here: [url]http://www.worldofspectrum.org/infoseekid.cgi?id=0027405[/u…
... somehow possible to use double buffer (128k) to overcome partial ... content from normal screen and draw on shadow screen, another copy ... interrupt:
[CODE] ld b, 5
loop:
ENDR
pop bc
djnz loop
...Making noises with the AYHow do you go about making noises from the AY chip in machine code? I'm wanting to make a pulsating humming noise that increases in volume as you ge…
... Ponloop LD BC,65533
LD D,(HL)
OUT (C),D
LD BC, ... tho the object/screen then
; LD A,n (10 ... inc to next channel
POP BC
DJNZ pulsevolloop
...Banked memory running slower?I've just compiled a TAP which includes bank6, it loads ok, but the routines that are paged in run slightly slower. The Z80 snapshot has no such pro…
... ld bc,#7ffd
ld hl,#ffff
ld de,#1110
ld ...
set_page
ld bc,#7ffd
swap
pop de
pop af
ld c,a
mem1282
pop hl
pop ... hl,de
ex de,hl
mem1283
djnz mem1282
ld sp ...Alkatraz Protection System - "How to" and compo?I'm thinking about writing a "how to" regarding the [URL="http://www.worldofspectrum.org/infoseekid.cgi?id=0020807"]Alkatraz Protection System[/URL].…
... ff $0ats
ld bc, $9a6f ; 5b06 ... 10/$15ts
ld sp, $658f ; 5b0b ... LD L,E
00200 CALL DEHR21
00210 POP HL ...64x48 monochrome big pixels display ideaHi. I was playing with this idea of having a simple 64x48 bytes buffer, 1 byte per pixel, then a renderer which would take that buffer and render it…
pop de
ld a,(de)
ld h,c
ld (hl),a
inc ... h
ld (hl),a
inc h
ld (hl ... /> ld sp,bufferline[N]
ret ;->
ld h,c
ld (hl ... 3 lines (32 bytes) to screen
