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1992-04-27
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1,107 lines
; ok, here it is... a real demo, go ahead and mess around, but maybe
; first make a backup for safety...
; this demo consists of 4 parts:
; - a picture on top of the screen, nothing happens with it
; - a scroll (blitter was used to copy new chars on the screen
; and to scroll the whole thing)
; - a starfield (using 1 sprite with more controlling words)
; - replay routine (not own-made, can be found on each noise-
; tracker disk)
; - equalisers, needs some knowledge of the replayroutine, like
; when a new note is played. (see near the bottom of source)
; the lines marked with * can be changed when you for example take
; another picture or font etc...
; you are however not completely free to change the values in
; whatever you want (don't take a picture height of 7000 lines for
; example coz the demo won't work as it should)
; HOW TO PUT EVERYTHING TOGETHER
;--------------------------------
;
; first change everything as you like it, and test it.
; assemble it, (a) and save the object (wo) (that's ALL!!!)
; if you want to use another picture, draw it with dpaint, save it
; use IFFconvert to save it as RAW colors BEFORE. It must be 320 wide
; note down the height coz you must fill it in into the source (see ***)
section MYFIRSTDEMO,code_c ; force loading into CHIPMEM
main: movem.l a0-a6/d0-d7,-(a7)
move.l $4,a6
lea gfxname,a1
jsr -408(a6) ; open gfx library
move.l d0,gfxbase
jsr -132(a6) ; forbid interrupts
bsr fillcopper ;precalculation of some data
bsr calcfontdata ;
jsr mt_init ;init. of replayroutine
move.w $dff01c,d0 ;save INTENA
move.w $dff01e,d1 ; INTREQ
move.w $dff002,d2 ; DMACON
move.w #$7fff,$dff096 ; clear DMACON
move.w #%1000001111100000,$dff096 ; set needed DMA's
move.l #copperlist,$dff080 ;install new copper
clr.l $dff088 ;and start
movem.l a0-a6/d0-d7,-(a7)
loop: bsr waitvblank ; wait for 'timing'
bsr scroll ; do scroll routine
bsr eq_down ; lower equalisers
bsr movestars ; do starroutine
jsr mt_music ; do replayroutine
btst #6,$bfe001 ; check left ear
bne.s loop
movem.l (a7)+,a0-a6/d0-d7
or.w #$8000,d0 ; set the 'set/clr' bit
or.w #$8000,d1
or.w #$8000,d2
move.w d2,$dff096 ;restore values in regs
move.w d1,$dff09c ;
move.w d0,$dff09a ;
jsr mt_end ; end of replayroutine
move.l gfxbase,a1
move.l $26(a1),$dff080 ;restore copperlist
move.l $4,a6
jsr -414(a6) ;close lib
jsr -138(a6) ;permit interrupts
move.w #$8100,$dff096 ;turn on bitplane dma
;(just to be sure)
movem.l (a7)+,a0-a6/d0-d7
rts ;exit
*****************************************************************
* *
* All kinds of routines... *
* *
*****************************************************************
waitvblank:
cmp.b #$ff,$dff006
bne.s waitvblank
waitabitmore:
cmp.b #$20,$dff006
bne.s waitabitmore
rts
;--------------------------------------------------------------
waitblitter:
btst #14,$2(a5)
bne.s waitblitter
rts
;--------------------------------------------------------------
movestars:
lea.l star_speedtab,a0
lea.l stars,a1
move.l #c_numofstars-1,d0
mslp: move.b (a0)+,d1 ; a0 contains speed for each star
add.b d1,1(a1) ; 1(a1) = bits H8-H1 of contr.words
addq.l #8,a1 ; next set of controlling words
dbf d0,mslp
rts
;--------------------------------------------------------------
eq_down:cmp.w #$400,eq0+2
beq.s eq_d1
sub.w #$100,eq0+2
eq_d1: cmp.w #$400,eq1+2
beq.s eq_d2
sub.w #$100,eq1+2
eq_d2: cmp.w #$400,eq2+2
beq.s eq_d3
sub.w #$100,eq2+2
eq_d3: cmp.w #$400,eq3+2
beq.s eq_d4
sub.w #$100,eq3+2
eq_d4: rts
*****************************************************************
* *
* scroll *
* *
*****************************************************************
scroll:
tst.b delay ; if delay is not 0, delay=delay-1
beq.s doscroll ; only if delay=0, a scroll is done
subq.b #1,delay
bra endscroll
doscroll:
move.l #$dff000,a5 ; start of hardware regs in a5
lea.l s_pic,a0 ; this routine scrolls the
lea.l s_pic-2,a1 ; whole scrollpic by 4 bits
move.l #s_depth-1,d1 ; using the barrelshifter
scrollraster:
bsr waitblitter
move.l a0,$50(a5) ; source address
move.l a1,$54(a5) ; destin.address
move.w #$ffff,$44(a5) ; Firstwordmask
move.w #$ffff,$46(a5) ; Lastwordmask
clr.w $42(a5) ; bltcon1
clr.w $64(a5) ; modulo source = 0
clr.w $66(a5) ; modulo destin = 0
move.w #%1100100111110000,$40(a5) ; bltcon0
move.w #s_blitsize,$58(a5) ; trigger/size
add.l #s_planesize,a0 ; next plane src
add.l #s_planesize,a1 ; next plane dst
dbf d1,scrollraster ; loop until d1= -1
subq.b #4,charpos ; now, char has scrolled 4 pixels
tst.b charpos ; time for new char ?
bgt endscroll ; no !
move.l #f_endchartab,d1 ; we'll need this value often
; so let's put it in d1 (faster)
find_new_char:
move.l textptr,a2 ; pointer to text
move.b (a2)+,d2 ; take char (+increase)
tst.b (a2) ; next char = 0 ?
bne.s newchgo
move.l #textrestart,a2 ; then scroll restarts
newchgo:move.l a2,textptr ; save new pos.textptr
lea.l f_chartab,a3 ;this routine searches the
moveq.l #-1,d0 ;chartab for the startaddres
newchlp:addq.l #1,d0 ;of the char that we must
move.b (a3)+,d3 ;put on screen. This is a
cmp.l d1,a3 ;silly routine that is not
bgt.s specialhandler ;very fast. I'll rewrite it
cmp.b d2,d3 ;when I'm in a good mood.
bne.s newchlp ;
move.b #f_widthB*8,charpos ;
asl.w #2,d0 ;
add.l #f_startaddr,d0 ;
move.l d0,a0 ;
move.l (a0),a0 ;
endnewch:
; the next bit will copy 1 char from the charpic onto the
; scrollpic. a0 is the address of the char (source) which
; we managed to find using the previous routine.
; a1 (destination) is the right side of the scrollpic.
move.l #s_depth-1,d1
move.l #s_pic+s_widthB-f_widthB,a1 ;dest addr.
putch: bsr waitblitter
move.l a0,$50(a5) ; source a
move.l a1,$54(a5) ; destin.
move.w #$ffff,$44(a5) ; fwm
move.w #$ffff,$46(a5) ; lwm
clr.w $42(a5) ; con1
move.w #f_blitmoda,$64(a5) ; mod a
move.w #f_blitmodd,$66(a5) ; mod d
move.w #%0000100111110000,$40(a5) ; con0
move.w #f_blitsize,$58(a5) ; trigger/size
add.l #f_planesize,a0 ;next pl.a
add.l #s_planesize,a1 ;next pl.d
dbf d1,putch
endscroll:
rts
specialhandler:
cmp.b #"P",d2
bne.s eff2
move.b #50,delay
eff2: ; here you can add your
; own effects...
bra find_new_char
*****************************************************************
* *
* calculation of addresses and values for copperlist *
* *
*****************************************************************
fillcopper:
movem.l a0-a6/d0-d7,-(a7)
;installpicplanes:
lea.l p_planept,a0
move.l #p_pic,d0
move.w #$e0,d1
move.l #p_depth-1,d2
ipp: move.w d1,(a0)+
addq.w #2,d1
swap d0
move.w d0,(a0)+ ; this routine fills the
move.w d1,(a0)+ ; label p_planept with
addq.w #2,d1 ; values like $00e0hhhh
swap d0 ; $00e2llll etc... (bplpt)
move.w d0,(a0)+
add.l #p_planesize,d0
dbf d2,ipp
;instalpiccolors:
lea.l p_col,a0
lea.l p_colpt,a1
move.w #$180,d1
move.l #p_numofcol-1,d2 ; fills copper with
ipc: move.w d1,(a1)+ ; $01800xxx,$01820xxx etc
addq.w #2,d1 ; colors from picture
move.w (a0)+,(a1)+
dbf d2,ipc
;installscrollplanes:
lea.l s_planept,a0
move.l #s_pic,d0
move.w #$e0,d1 ; fills the BPLxPTH & L
move.l #s_depth-1,d2 ; for the scroll-pic
ifp: move.w d1,(a0)+
addq.w #2,d1
swap d0
move.w d0,(a0)+
move.w d1,(a0)+
addq.w #2,d1
swap d0
move.w d0,(a0)+
add.l #s_planesize,d0
dbf d2,ifp
;install colored lines
lea.l c_line1,a0
lea.l c_line2,a1
lea.l c_coltab,a2 ; fills c_line1 and c_line2
move.l #c_numofdivs-1,d0 ; with $01800xxx to create
move.l #$01800000,d1 ; the effect of a multi-
icl: move.l d1,d2 ; colored line.
move.w (a2)+,d2
move.l d2,(a0)+
move.l d2,(a0)+
move.l d2,(a1)+
move.l d2,(a1)+
dbf d0,icl
;install SPRxPTH & SPRxPTH for sprite 1 (starfield)
move.l #stars,d0
move.l #$120,d1 ; spr0ptH
lea.l spr1pt,a0
move.w d1,(a0)
addq.w #2,d1 ; spr0ptL
move.w d1,4(a0)
addq.w #2,d1
move.w d0,6(a0) ; lowword
swap d0
move.w d0,2(a0) ; highword
addq.l #8,a0
;install SPRxPTH & L for 7 other sprites (not used)
moveq.l #6,d2
isp: move.l #zerosprite,d0
move.w d0,6(a0) ; lowword
swap d0
move.w d0,2(a0) ; highword
move.w d1,(a0) ; sprXptH
addq.w #2,d1
move.w d1,4(a0) ; sprXptL
addq.w #2,d1
addq.l #8,a0 ; next set of SPRxPT
dbf d2,isp
;install sprite data (vpos & hpos) for each subsprite...
lea.l stars,a0
lea.l star_hpostab,a1
clr.l d0 ; 1st line sprite = 0
; (right after start lowerzone)
move.l #c_numofstars-1,d1
isd: move.b d0,(a0)+ ; V7-V0
move.b (a1)+,(a0)+ ; H8-H1
addq.w #1,d0
move.b d0,(a0)+ ; L7-L0
move.b #6,(a0)+ ; L8=1, V8=1
addq.w #1,d0
addq.l #4,a0
dbf d1,isd
;install color for each subsprite according to speed (slow=dark)
lea.l c_starblock,a0
lea.l star_speedtab,a1
lea.l colortab,a2
clr.l d0
move.l #c_numofstars-1,d1
ics: move.b d0,(a0)+ ; these 4 lines create in
addq.b #2,d0 ; the copperlist a wait-
move.b #$0f,(a0)+ ; instr.
move.w #$fffe,(a0)+ ;
move.w #$01a2,(a0)+ ; color17 (sprite1col1)
moveq.l #0,d2
move.b (a1)+,d2 ; check speed of current star
asl.w #1,d2 ; speed * 2 = offset for colortab : example:
; speed=1, offset=2 (=2nd word in tab)
; speed=2, offset=4 (=3th word in tab)
move.w (a2,d2),(a0)+
dbf d1,ics
endfc: movem.l (a7)+,a0-a6/d0-d7
rts
*****************************************************************
* *
* calculation of constants *
* *
*****************************************************************
calcfontdata:
movem.l a0-a6/d0-d7,-(a7)
;calc startaddr of each char in the pic
lea.l f_pic,a0
lea.l f_startaddr,a1
move.l #f_totheight,d2 ; fills the f_startaddr-tab
move.l #f_widthW,d1 ; with the startaddresses of
cca1: move.l #f_totwidthW,d0 ; the different chars in the
cca2: move.l a0,(a1)+ ; picture. This way, the 1st
add.l #f_widthB,a0 ; value in this tab will be
sub.l d1,d0 ; the addres where the shape
cmp.l #1,d0 ; of the 1st char starts etc
bgt.s cca2 ;(used in the silly routine)
nextrow:add.l #[f_height-1]*f_totwidthB,a0
sub.l #f_height,d2
bgt.s cca1
endcfd: movem.l (a7)+,a0-a6/d0-d7
rts
*****************************************************************
* *
* data *
* *
*****************************************************************
******************* sprite stuff **********************
c_numofstars= 20
stars: blk.l 2*c_numofstars,$00010000
; there are 2 longwords for each 'subsprite', the first longword
; contains the controlling words for the sprite, the second
; longword contains the shapedata. OUr sprites are only 1 line high.
zerosprite: dc.l 0 ; last 2 words zero to end spriteDMA
star_hpostab:
dc.b 100,20,46,240,2,78,172,120,200,154,210,180,51,220
dc.b 10,90,150,32,99,24,57,0,0,0,0,0,0,0,0,0,0
; contains starting position (horiz) for each star.
star_speedtab:
dc.b 1,2,1,2,3,3,1,3,2,2,1,2,3,1,2,2,1,2,3,2,1,3,2,1,2,1,3,1
dc.b 0,0,0,0,0,0,0
; contains speed for each star. By adding this value to the current
; hor.position, the star will seem to move to the right with a
; certain speed.
colortab:
dc.w $000,$444,$888,$aaa,$fff
; contains 5 words = colors for each speed
******************* font definitions **********************
f_depth= 2 ; planes *
f_height= 49 ; height 1 char *
f_totheight= 245 ; height charpic *
f_widthW= 2 ; width 1 char WORDS *
f_totwidthW= 288/16 ; width charpic WORDS *
f_widthB= f_widthW*2
f_totwidthB= f_totwidthW*2
f_planesize= f_totwidthB*f_totheight
f_picsize= f_planesize*f_depth
f_numofcol= 2^f_depth
f_pic: incbin "df0:mp.288x245x2" ; *
f_startaddr:
blk.l [[f_totheight/f_height]+1]*[[f_totwidthW/f_widthW]+1],0
f_chartab:
dc.b "abcdefghijklmnopqrstuvwxyz.,!?:[]-0123456789 "
f_endchartab:
dc.b 0
even
f_blitsize= 64*f_height+f_widthW
f_blitmoda= [f_totwidthB-f_widthB]
******************** scroll definitions ***********************
s_height= 51 ;lines
s_width= 384 ;bits
s_topline= $f5 ; < $ff !! **
s_depth= f_depth
s_widthB= s_width/8
s_widthW= s_width/16
s_planesize= s_height*s_widthB
s_bottline= s_topline+s_height-[2*f_height]
s_mod= [s_widthB-40]
s_buff: blk.b 4 ; small bug : a bit of blitted part
; of the scroll will land here
s_pic: blk.b [s_planesize*s_depth]
s_blitsize= 64*s_height+s_widthW
f_blitmodd= [s_widthB-f_widthB]
************************* the logo *********************************
p_depth= 5 ; * adjust these values
p_height= 190 ;lines * if you drew another
p_width= 320 ;bits * logo !! (width must
p_topline= 40 ; * be 320!)
p_widthB= p_width/8
p_widthW= p_width/16
p_planesize= p_height*p_widthB
p_numofcol= 2^p_depth
p_mod= p_widthB-40
p_col: incbin "df0:abyss.320x190x5" ; *
p_pic= p_col+p_numofcol*2
*********************** various stuff ******************************
delay: dc.b 0 ; counter to keep track on
; delay for scroll (effect1)
charpos: dc.b f_widthW*16 ; counter to keep track on
; when to put a new char on
; the screen.
; capital 'P' will pause the scroller for a while...
; only use chars that are listed in the chartab...
text: dc.b "here we go..." ; this text will be shown only once...
textrestart: ; this part will be restarted each time
dc.b " amigafreaks in pretoria and surroundings now have their own"
dc.b " bulletin board system... call now for free downloading"
dc.b " (12)73-9069 PP the abyss PP sysops are midnight horror and"
dc.b " atlantic dolphin low rates - hot stuff - for amiga "
dc.b "and pc !! silly demo coded by cool-g long ago ! "
dc.b 0 ; add dc.b 0 at end of scrolltext !!
even
textptr: dc.l text ; pointer to the position in
; the scrolltext (don't change!)
gfxbase: dc.l 0
gfxname:
dc.b "graphics.library",0
even
c_numofdivs= 32
c_coltab: dc.w 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
dc.w 15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0
********************************************************************
copperlist:
dc.l $00960100 ; turn off bitpl.DMA
spr1pt: blk.l 8*2,0 ; 8 sprites, each one with
; SPRxPTH & SPRxPTL
p_colpt: blk.l p_numofcol,0 ;room for pic colors
p_planept: blk.l p_depth*2,0 ;and BPLxPT
dc.l $008e2921,$009029c1 ;diw start/stop
dc.l $00920030,$009400c8 ;ddf start/stop
dc.l $01020088 ;bplcon1(smooth pos)
dc.w $0108,p_mod,$010a,p_mod ;BPLMOD even/odd
dc.b $01,$00,p_depth*16,$00 ;BPLCON0 (#planes)
dc.b p_topline,$0f,$ff,$fe ;wait for topline
dc.l $00968100 ;turn on bitpl.DMA
dc.l $600ffffe
eq0: dc.l $01800000
dc.l $680ffffe
dc.l $01800000
dc.l $700ffffe
eq1: dc.l $01800800
dc.l $780ffffe
dc.l $01800000
dc.l $800ffffe
eq2: dc.l $01800800
dc.l $880ffffe
dc.l $01800000
dc.l $900ffffe
eq3: dc.l $01800800
dc.l $980ffffe
dc.l $01800000
dc.b p_topline+p_height,$0f,$ff,$fe
;wait for bottomline
dc.l $00960100 ;turn off bitpl.dma
f_colpt: dc.l $01800000,$01820008 ; scroll colors ***
dc.l $01840004,$0186044a
s_planept: blk.l s_depth*2,0 ; scroll BPLxPT's
dc.l $01020000 ;bplcon1
dc.l $00920030,$009400d0 ;ddfstart/stop
dc.w $0108,s_mod-2,$010a,s_mod-2 ;BPLMOD
dc.b $01,$00,s_depth*16,$00 ;BPLCON0
dc.b s_topline,$0f,$ff,$fe ;wait for topline
c_line1: blk.l 2*c_numofdivs,0 ;room for colored line
dc.l $01040000 ;priority of sprites
dc.b s_topline+4,$0f,$ff,$fe
dc.l $00968100 ;turn on bitplanes
dc.l $ffdffffe ;wait for lower zone
c_starblock: blk.l 2*c_numofstars,0 ;room for starcolors
dc.b s_topline+f_height+6-256,$0f,$ff,$fe
dc.l $00960100 ;end of scrollpic
c_line2: blk.l 2*c_numofdivs,0 ;2nd colored line
dc.l $fffffffe ;end of copperlist1
; now follows the noisetracker replay-routine, which can be found
; on each disk with noisetracker. Simply build it into your own
; routine, and READY !!
mt_data:incbin "df0:mod.so what..." ; ****
;
; NoisetrackerV1.0 replayroutine
; Mahoney & Kaktus - HALLONSOFT 1989
;
mt_init:movem.l a0-a6/d0-d7,-(a7)
lea mt_data,a0
move.l a0,a1
add.l #$3b8,a1
moveq #$7f,d0
moveq #0,d1
mt_loop:move.l d1,d2
subq.w #1,d0
mt_lop2:move.b (a1)+,d1
cmp.b d2,d1
bgt.s mt_loop
dbf d0,mt_lop2
addq.b #1,d2
lea mt_samplestarts(pc),a1
asl.l #8,d2
asl.l #2,d2
add.l #$43c,d2
add.l a0,d2
move.l d2,a2
moveq #$1e,d0
mt_lop3:clr.l (a2)
move.l a2,(a1)+
moveq #0,d1
move.w 42(a0),d1
asl.l #1,d1
add.l d1,a2
add.l #$1e,a0
dbf d0,mt_lop3
or.b #$2,$bfe001
move.b #$6,mt_speed
clr.w $dff0a8
clr.w $dff0b8
clr.w $dff0c8
clr.w $dff0d8
clr.b mt_songpos
clr.b mt_counter
clr.w mt_pattpos
movem.l (a7)+,a0-a6/d0-d7
rts
mt_end: clr.w $dff0a8
clr.w $dff0b8
clr.w $dff0c8
clr.w $dff0d8
move.w #$f,$dff096
rts
mt_music:
movem.l d0-d4/a0-a3/a5-a6,-(a7)
lea mt_data,a0
addq.b #$1,mt_counter
move.b mt_counter,D0
cmp.b mt_speed,D0
blt.s mt_nonew
clr.b mt_counter
bra mt_getnew
mt_nonew:
lea mt_voice1(pc),a6
lea $dff0a0,a5
bsr mt_checkcom
lea mt_voice2(pc),a6
lea $dff0b0,a5
bsr mt_checkcom
lea mt_voice3(pc),a6
lea $dff0c0,a5
bsr mt_checkcom
lea mt_voice4(pc),a6
lea $dff0d0,a5
bsr mt_checkcom
bra mt_endr
mt_arpeggio:
moveq #0,d0
move.b mt_counter,d0
divs #$3,d0
swap d0
tst.w d0
beq.s mt_arp2
cmp.w #$2,d0
beq.s mt_arp1
moveq #0,d0
move.b $3(a6),d0
lsr.b #4,d0
bra.s mt_arp3
mt_arp1:moveq #0,d0
move.b $3(a6),d0
and.b #$f,d0
bra.s mt_arp3
mt_arp2:move.w $10(a6),d2
bra.s mt_arp4
mt_arp3:asl.w #1,d0
moveq #0,d1
move.w $10(a6),d1
lea mt_periods(pc),a0
moveq #$24,d7
mt_arploop:
move.w (a0,d0.w),d2
cmp.w (a0),d1
bge.s mt_arp4
addq.l #2,a0
dbf d7,mt_arploop
rts
mt_arp4:move.w d2,$6(a5)
rts
mt_getnew:
lea mt_data,a0
move.l a0,a3
move.l a0,a2
add.l #$c,a3
add.l #$3b8,a2
add.l #$43c,a0
moveq #0,d0
move.l d0,d1
move.b mt_songpos,d0
move.b (a2,d0.w),d1
asl.l #8,d1
asl.l #2,d1
add.w mt_pattpos,d1
clr.w mt_dmacon
lea $dff0a0,a5
lea mt_voice1(pc),a6
bsr.s mt_playvoice
lea $dff0b0,a5
lea mt_voice2(pc),a6
bsr.s mt_playvoice
lea $dff0c0,a5
lea mt_voice3(pc),a6
bsr.s mt_playvoice
lea $dff0d0,a5
lea mt_voice4(pc),a6
bsr.s mt_playvoice
bra mt_setdma
mt_playvoice:
move.l (a0,d1.l),(a6)
addq.l #4,d1
moveq #0,d2
move.b $2(a6),d2
and.b #$f0,d2
lsr.b #4,d2
move.b (a6),d0
and.b #$f0,d0
or.b d0,d2
tst.b d2
beq.s mt_setregs
moveq #0,d3
lea mt_samplestarts(pc),a1
move.l d2,d4
subq.l #$1,d2
asl.l #2,d2
mulu #$1e,d4
move.l (a1,d2.l),$4(a6)
move.w (a3,d4.l),$8(a6)
move.w $2(a3,d4.l),$12(a6)
move.w $4(a3,d4.l),d3
tst.w d3
beq.s mt_noloop
move.l $4(a6),d2
asl.w #1,d3
add.l d3,d2
move.l d2,$a(a6)
move.w $4(a3,d4.l),d0
add.w $6(a3,d4.l),d0
move.w d0,8(a6)
move.w $6(a3,d4.l),$e(a6)
move.w $12(a6),$8(a5)
bra.s mt_setregs
mt_noloop:
move.l $4(a6),d2
add.l d3,d2
move.l d2,$a(a6)
move.w $6(a3,d4.l),$e(a6)
move.w $12(a6),$8(a5)
mt_setregs:
move.w (a6),d0
and.w #$fff,d0
beq mt_checkcom2
move.b $2(a6),d0
and.b #$F,d0
cmp.b #$3,d0
bne.s mt_setperiod
bsr mt_setmyport
bra mt_checkcom2
mt_setperiod:
move.w (a6),$10(a6)
and.w #$fff,$10(a6)
move.w $14(a6),d0
move.w d0,$dff096
clr.b $1b(a6)
move.l $4(a6),(a5)
move.w $8(a6),$4(a5)
move.w $10(a6),d0
and.w #$fff,d0
move.w d0,$6(a5)
move.w $14(a6),d0
or.w d0,mt_dmacon
bra mt_checkcom2
mt_setdma:
move.w #$12c,d0
mt_wait:dbf d0,mt_wait
move.w mt_dmacon,d0
or.w #$8000,d0
move.w d0,$dff096
move.w #$12c,d0
mt_wai2:dbf d0,mt_wai2
lea $dff000,a5
lea mt_voice4(pc),a6
move.l $a(a6),$d0(a5)
move.w $e(a6),$d4(a5)
lea mt_voice3(pc),a6
move.l $a(a6),$c0(a5)
move.w $e(a6),$c4(a5)
lea mt_voice2(pc),a6
move.l $a(a6),$b0(a5)
move.w $e(a6),$b4(a5)
lea mt_voice1(pc),a6
move.l $a(a6),$a0(a5)
move.w $e(a6),$a4(a5)
add.w #$10,mt_pattpos
cmp.w #$400,mt_pattpos
bne.s mt_endr
mt_nex: clr.w mt_pattpos
clr.b mt_break
addq.b #1,mt_songpos
and.b #$7f,mt_songpos
move.b mt_songpos,d1
cmp.b mt_data+$3b6,d1
bne.s mt_endr
move.b mt_data+$3b7,mt_songpos
mt_endr:tst.b mt_break
bne.s mt_nex
; equaliser check. if the first word of mt_voiceX is not zero, a new
; note was played.
lea.l mt_voice1,a6
tst.w (a6)
beq.s mt_chk1
lea.l eq0,a6
move.w #$f00,2(a6)
mt_chk1:lea.l mt_voice2,a6
tst.w (a6)
beq.s mt_chk2
lea.l eq1,a6
move.w #$f00,2(a6)
mt_chk2:lea.l mt_voice3,a6
tst.w (a6)
beq.s mt_chk3
lea.l eq2,a6
move.w #$f00,2(a6)
mt_chk3:lea.l mt_voice4,a6
tst.w (a6)
beq.s mt_chk4
lea.l eq3,a6
move.w #$f00,2(a6)
mt_chk4:
movem.l (a7)+,d0-d4/a0-a3/a5-a6
rts
mt_setmyport:
move.w (a6),d2
and.w #$fff,d2
move.w d2,$18(a6)
move.w $10(a6),d0
clr.b $16(a6)
cmp.w d0,d2
beq.s mt_clrport
bge.s mt_rt
move.b #$1,$16(a6)
rts
mt_clrport:
clr.w $18(a6)
mt_rt: rts
mt_myport:
move.b $3(a6),d0
beq.s mt_myslide
move.b d0,$17(a6)
clr.b $3(a6)
mt_myslide:
tst.w $18(a6)
beq.s mt_rt
moveq #0,d0
move.b $17(a6),d0
tst.b $16(a6)
bne.s mt_mysub
add.w d0,$10(a6)
move.w $18(a6),d0
cmp.w $10(a6),d0
bgt.s mt_myok
move.w $18(a6),$10(a6)
clr.w $18(a6)
mt_myok:move.w $10(a6),$6(a5)
rts
mt_mysub:
sub.w d0,$10(a6)
move.w $18(a6),d0
cmp.w $10(a6),d0
blt.s mt_myok
move.w $18(a6),$10(a6)
clr.w $18(a6)
move.w $10(a6),$6(a5)
rts
mt_vib: move.b $3(a6),d0
beq.s mt_vi
move.b d0,$1a(a6)
mt_vi: move.b $1b(a6),d0
lea mt_sin(pc),a4
lsr.w #$2,d0
and.w #$1f,d0
moveq #0,d2
move.b (a4,d0.w),d2
move.b $1a(a6),d0
and.w #$f,d0
mulu d0,d2
lsr.w #$6,d2
move.w $10(a6),d0
tst.b $1b(a6)
bmi.s mt_vibmin
add.w d2,d0
bra.s mt_vib2
mt_vibmin:
sub.w d2,d0
mt_vib2:move.w d0,$6(a5)
move.b $1a(a6),d0
lsr.w #$2,d0
and.w #$3c,d0
add.b d0,$1b(a6)
rts
mt_nop: move.w $10(a6),$6(a5)
rts
mt_checkcom:
move.w $2(a6),d0
and.w #$fff,d0
beq.s mt_nop
move.b $2(a6),d0
and.b #$f,d0
tst.b d0
beq mt_arpeggio
cmp.b #$1,d0
beq.s mt_portup
cmp.b #$2,d0
beq mt_portdown
cmp.b #$3,d0
beq mt_myport
cmp.b #$4,d0
beq mt_vib
move.w $10(a6),$6(a5)
cmp.b #$a,d0
beq.s mt_volslide
rts
mt_volslide:
moveq #0,d0
move.b $3(a6),d0
lsr.b #4,d0
tst.b d0
beq.s mt_voldown
add.w d0,$12(a6)
cmp.w #$40,$12(a6)
bmi.s mt_vol2
move.w #$40,$12(a6)
mt_vol2:move.w $12(a6),$8(a5)
rts
mt_voldown:
moveq #0,d0
move.b $3(a6),d0
and.b #$f,d0
sub.w d0,$12(a6)
bpl.s mt_vol3
clr.w $12(a6)
mt_vol3:move.w $12(a6),$8(a5)
rts
mt_portup:
moveq #0,d0
move.b $3(a6),d0
sub.w d0,$10(a6)
move.w $10(a6),d0
and.w #$fff,d0
cmp.w #$71,d0
bpl.s mt_por2
and.w #$f000,$10(a6)
or.w #$71,$10(a6)
mt_por2:move.w $10(a6),d0
and.w #$fff,d0
move.w d0,$6(a5)
rts
mt_portdown:
moveq #0,d0
move.b $3(a6),d0
add.w d0,$10(a6)
move.w $10(a6),d0
and.w #$fff,d0
cmp.w #$358,d0
bmi.s mt_por3
and.w #$f000,$10(a6)
or.w #$358,$10(a6)
mt_por3:move.w $10(a6),d0
and.w #$fff,d0
move.w d0,$6(a5)
rts
mt_checkcom2:
move.b $2(a6),d0
and.b #$f,d0
cmp.b #$e,d0
beq.s mt_setfilt
cmp.b #$d,d0
beq.s mt_pattbreak
cmp.b #$b,d0
beq.s mt_posjmp
cmp.b #$c,d0
beq.s mt_setvol
cmp.b #$f,d0
beq.s mt_setspeed
rts
mt_setfilt:
move.b $3(a6),d0
and.b #$1,d0
asl.b #$1,d0
and.b #$fd,$bfe001
or.b d0,$bfe001
rts
mt_pattbreak:
not.b mt_break
rts
mt_posjmp:
move.b $3(a6),d0
subq.b #$1,d0
move.b d0,mt_songpos
not.b mt_break
rts
mt_setvol:
cmp.b #$40,$3(a6)
ble.s mt_vol4
move.b #$40,$3(a6)
mt_vol4:move.b $3(a6),$8(a5)
rts
mt_setspeed:
cmp.b #$1f,$3(a6)
ble.s mt_sets
move.b #$1f,$3(a6)
mt_sets:move.b $3(a6),d0
beq.s mt_rts2
move.b d0,mt_speed
clr.b mt_counter
mt_rts2:rts
mt_sin:
dc.b $00,$18,$31,$4a,$61,$78,$8d,$a1,$b4,$c5,$d4,$e0,$eb,$f4,$fa,$fd
dc.b $ff,$fd,$fa,$f4,$eb,$e0,$d4,$c5,$b4,$a1,$8d,$78,$61,$4a,$31,$18
mt_periods:
dc.w $0358,$0328,$02fa,$02d0,$02a6,$0280,$025c,$023a,$021a,$01fc,$01e0
dc.w $01c5,$01ac,$0194,$017d,$0168,$0153,$0140,$012e,$011d,$010d,$00fe
dc.w $00f0,$00e2,$00d6,$00ca,$00be,$00b4,$00aa,$00a0,$0097,$008f,$0087
dc.w $007f,$0078,$0071,$0000,$0000
mt_speed: dc.b $6
mt_songpos: dc.b $0
mt_pattpos: dc.w $0
mt_counter: dc.b $0
mt_break: dc.b $0
mt_dmacon: dc.w $0
mt_samplestarts:blk.l $1f,0
mt_voice1: blk.w 10,0
dc.w $1
blk.w 3,0
mt_voice2: blk.w 10,0
dc.w $2
blk.w 3,0
mt_voice3: blk.w 10,0
dc.w $4
blk.w 3,0
mt_voice4: blk.w 10,0
dc.w $8
blk.w 3,0