-
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…
... count
ld d, line_data00/256
ld a, (hl)
ld e, a ... )
inc l
ld h, (hl)
ld l, a
push ...
ld a, (de)
ld h, line_data00/256
ld l, a
ld c ... -
Calculate screenaddressWho knows where the topic about the fastest screenaddressroutine is? I can't find it in a search.. The fastest routine was to load a large table of …
... to load a large table of all the screenaddresses ... [code]
LD H,250 ; Table 256 * 256 = 64000
LD L,C
LD A,(HL ... Lo-byte
INC H
LD H,(HL) ; Fetch Hi-byte ...
LD L,A
RET ... -
IM2 Machine Code Sprites Example Code Using Char Based SystemFurther to my earlier post, here are sprites running using char method with IM2 driving it Note, for 48k spectrum using TASM [code] ; ***********…
... ;Building up a table with
ld bc,0FDh ;253*256+253, i ... , eg. L=10
LD H,0FAh ; Point H to FA00h, so HL ... H ; Increase H, thus moving 256 bytes forward in memory to FB0Ah
LD H ... -
Problem with rotating procedureHi folks! I wrote a proc in z80 asm, based on: x' = x * cos (z) - y * sin (z) y' = x * sin (z) + y * cos (z) I used a precalculated table of sin a…
...
I used a precalculated table of sin and cos data ...
ld h,a
ld a,c
ld c,h
... 255,-255
dw -256,-255,-255,-255,-255,-255 ... org $b600
cosx: dw 256,255,255,255,255,255 ... 255,-255
dw -256,-255,-255,-255,-255,-255 ... -
Tips on optimizing some newbie assembly routinesI'm starting to learn some assembly language. The best way to learn is to actually code something you are going to use, so I'm creating a very simple…
... grid of characters, a table of characters, and ... # and attribute) and the table of characters (named _MB23_tileset) ... just a 2048 byte table of 256 8x8 tiles.
... push de
ld h, 0
ld l, a
... -
CMWC random number generator for Z80Seeing the interest regarding the [URL="http://www.worldofspectrum.org/forums/showthread.php?t=23070"]Xor-Shift random number generator for Z80[/URL]…
... />
ld b,0
ld c,e
ld hl,table
add ...
ld e,a
ld h,c ; t = 256 * y
ld l ... computation itself. Having the table aligned to 256 byte boundary could be ... -
help in byte mirroring.I need some help. What is the best way to mirror the byte? (for ex. 10010011 -> 11001001) I mean, if there is a simple way to do it (may be with OR, …
... the table method:
LD A,normalbyte
LD H,tablehighbyte
LD L ... there - you loose 256 bytes in a table but you want to ... to mirror you can sacrafice 256 bytes which is a lot ... -
need help with speed optimization. this procedure draws a sprite with mask from memory onto the screen with x-coordinate in pixels. it doesn't shift sprites in realtime, it just uses …
... ,C000H ;placing table at the beginning of
;a 256 byte page ... /> ADD A,A
LD H,C0H ;table with preshifted mask bytes for ... a table with all bytes preshifted to all steps.
LD H,A ... -
IM2 Machine Code Sprites Example Code Using Char Based SystemFurther to my earlier post, here are sprites running using char method with IM2 driving it Note, for 48k spectrum using TASM [code] ; ***********…
... a table with
ld bc,0FDh ;253*256+253 ... =10
LD H,0FAh ; Point H to FA00h, so ... H ; Increase H, thus moving 256 bytes forward in memory to FB0Ah
LD H ... /> or 88
ld h,a
ret
IM2 Machine Code Sprites Example Code Using Char Based SystemFurther to my earlier post, here are sprites running using char method with IM2 driving it Note, for 48k spectrum using TASM [code] ; ***********…
... FC00, get the offset table horizontally
LD C,(IX+2) ; X ... H ; Increase H, thus moving 256 bytes forward in memory to FB0Ah
LD H ... ;Building up a table with
ld bc,0FDh ;253*256+253, i ...JSW - Is this possible?There's an object in the Conservatory Roof which I reckon cannot be collected without losing a life. There's a snapshot taken in the Conservatory …
... c in the Guardian-Class Table (40960 + 8*c) ... e. index into Guardian-Class Table)
RES 7,L ; ... 128 guardian-classes)
LD H,20 ; HL = 256*20 + L
... ADD HL,HL ; HL = 2*(256*20 + L)
ADD ... ADD HL,HL ; HL = 8*(256*20 + L) = 40960 + 8 ...FrameSyncIt was many many years ago since i programmed assembly on the spectrum but I just picked it up again for fun. Now this is one thing I can't remember…
... (N * 256 is the address of your IM2 vector table, ADDR is ... />
ld hl,N*256
ld a,h
ld i,a
im 2
Loop: ld ...
inc h
ld (hl),h
ld l,h
ld (hl),0C3h ...Convert x,y to Attribute Address in AssemblyWhat is the fastest way, given x,y (in hl) to return the attribute address?
... a 512 byte lookup table, you might want to ... ld a,h to satisfy the original criteria)
ld h,lookup_hi
ld ... e,(hl)
inc h
ld d,(hl ... br /> or e
ld e,a
... to be on a 256-byte boundary, of course ...Spectrum Screen Memory MapWhat's the advantage (mistery?) behind ULA's spectrum screen memory interpretation? 6144 bytes divided into 3 blocks, 2048 bytes long. if you want t…
... the character you just add 256 to the current screen address ... table, and get the screen address with something like:
[CODE]LD H ... , HIBYTE(ScreenTable)
LD L, Y-COORD
LD A, (HL)
INC H
LD L, (HL)
LD H, A ...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?
... .
[code]
LD SP,VRAM_TABLE + 2*Y-position ... />
_vramTableBase:
DS 256*numberOfColumns we have window limit ... has it's own table
LD A,_positionX X ... base of vram_table
LD H,A
LD A,_positionY
ADD ...Delay routineAs some people are aware, I have recently starting writing a [url=http://fuse-emulator.svn.sourceforge.net/viewvc/fuse-emulator/trunk/fusetest/]autom…
... a ; 4
or h ; 4
jr ... sub l ; 4
ld hl,base + ( 256 - d2 )
; ... /> ret
table db t14&255,t15 ...Project: M.u.l.e.Wokani came up with a great idea about trying an open-development approach for spectrum games, and I thought why not try with a game I have under dev…
... /> ld hl,49152
ld bc,(9*256)
push hl
ld de ... />
#asm
ld hl,(23*256)
call zx_cyx2saddr_callee + ASMDISP_ZX_CYX2SADDR_CALLEE ... updated files.
Create symbol table file.
Link/relocate assembled ...Bouncing BallsPfrrt, I am back from lunch, playing the first raw version of BOUNCING BALLS It is very addictive! As stated here [URL]http://www.worldofspectru…
... squaring can be done with table look-up. There should ... ld h,sqrtab
ld a,(hl)
inc l
ld h,(hl)
ld ... defw 16
....
defw 256
defw 289
defw ...Screen access in assemblerI am again troubled by the unusal screen design of the Spectrum. :) If I want to do something with, say, a 16x16 bit block of the screen (in the sam…
... /> If you'll align table on 256 bytes boundary and make it ... 512 bytes long, with 256 LSB first (192 actual and ... 64 dummy values) and 256 HSB next, you could fetch ... :
[code] ld h, HSB of table address
ld l, Y coord ...A scrolling starfield - help needed!I have been messing on my speccy again recently and tried to do a scrolling (parallax - maybe) starfield. I know how to scroll using machine code but…
...
ld bc,ZXScrTab ; add the addr of the table
add ... in the lookup table containing the address
ld c,(hl) ; get ... give offset to screenbase (16384/256)
LD H,A ; store the result ...A scrolling starfield - help needed!I have been messing on my speccy again recently and tried to do a scrolling (parallax - maybe) starfield. I know how to scroll using machine code but…
... would use a look up table of screen row addresses. (I ... posted the table needed to do this, previously ... give offset to screenbase (16384/256)
LD H,A ; store the result ...A scrolling starfield - help needed!I have been messing on my speccy again recently and tried to do a scrolling (parallax - maybe) starfield. I know how to scroll using machine code but…
... aforementioned row address look up table. By the time I' ... calculated the index into the table and extracted the address into ... doesn't use a lookup table.
[code]
... give offset to screenbase (16384/256)
LD H,A ; store the result ...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 …
... /> ; B=(2048*(D div 8))/256 -> B=8*(D div ... /> INC H ; next line on screen (INC HL by 256)
... here
LD A,D
LD H,E
LD L,253
table such that the BIT FADE ... at the end of the table, such that the screen ...How does the Speccy deal with the Character Set?Hi All, Can anyone spare a little time to explain to me the basic Assembly method of how the Speccy interprets and retrieves Characters to print on …
... the screen address with 256
6 Repeat ... br /> LD L,A
LD H,0
LD BC,(23606) ... ,BC ;add table offset
LD B,8 ...Rainbow Generator for 48K Spectrum using PUSHThis is what I came up with from [B]gasman[/B]'s suggestions. It's stable in ZXSpin and ZX32 simulating a 48K Speccy. Anyone like to try it on the …
... x; #4; "some text";. All 256 characters can be redefined. USR ... equ 0x5c36 ; start of font - 256
chans equ 0x5c4f ; start ... ,0x3b ; High byte of address table...
ld i,a ; ...goes into ... ; to a
ld h, 0 ; clear h
ld l, a ; low byte ...AY programming and notes frequencyHello everybody, I'm Targhan from the french CPC group Arkos, perhaps you've heard of us. I'm currently working on a music tool and I'd like to k…
... br /> ; note table data depacker
ld de,T_PACK
ld bc,T1_ ... /> ld (CurEDel),a
ld h,a
ld l,a
ld ( ... br /> T_PACK DB #06EC*2/256,#06EC*2
DB #0755 ... $
VT_ DS 256 ;CreatedVolumeTableAddress
EnvBase ...AY programming and notes frequencyHello everybody, I'm Targhan from the french CPC group Arkos, perhaps you've heard of us. I'm currently working on a music tool and I'd like to k…
...
ld (CurEDel),a
ld h,a
ld l,a
ld (CurESld ... />
T_PACK DB #06EC*2/256,#06EC*2
DB #0755 ... 0C55
DB #066D*2/256,#066D*2
DB #06CF ... $
VT_ DB "VOLUME TABLE"
DS 244 ;CreatedVolumeTableAddress
