GAME1.TXT

*FOR PUBLIC'S GAME, BOTH
*SHOULD BE     0
INVINCIBLE EQU 0 *0=NO
PAUSECLEAR EQU 0 *1=NO
OBLEN  EQU   39
NLINK  EQU   0
LLINK  EQU   2
TRKDRV EQU   5
NEWPOS EQU   7
ANGLE  EQU   9
TYPE   EQU   10
STATUS EQU   4
IBLOCK EQU   11
DRAGHITS EQU 11
DRAGHITINC EQU 12
IJUMP  EQU   13
SHIPX  EQU   13
IPOS   EQU   15
SQDPOS EQU   17
SYNCB  EQU   19
SHIPY  EQU   21
ADDSHIPX EQU 23
ADDSHIPY EQU 25
*NOTUSED YET 21
OFFSET EQU   23
CANGLE EQU   24
SPCDRV EQU   25
****************
DRAGCOLWAIT EQU 27
DRAGCOLAT   EQU 28
DRAGCOLS    EQU 29
****************
GOTRACK EQU  27
IWAIT  EQU   29
IWAIT2 EQU   31
IWAIT3 EQU   32
BOFLASH EQU  34
*TRACK VAR'S
DOANGLE EQU  29
TRACKSPEED EQU 31
TRACKSP EQU  32
TRACKLEN EQU 33
BULARMOR EQU 27
*BLOWUP VAR'S
BLFR   EQU   27
BLBL   EQU   29
BLPL   EQU   31
*COUMACAUSY VAR'S
CMPOS  EQU   27
CMTP   EQU   29
GASBUGHIT EQU 27
CPINSQ EQU   27
INSQDI EQU   29
LLEN   EQU   27
LMD    EQU   29
LND    EQU   31
LCD    EQU   33
LCOM   EQU   35
MOTHER EQU   37
ALIVE  EQU   0
APBUG  EQU   1
AOFSET EQU   3
CHILD  EQU   7
CLBC   EQU   21
CLSHT  EQU   21

       SETDP $E0
GAMEDP
       LBRA  GAME

*ENTRY: B= LEVEL ON
CALCLEV MACR
       TFR   B,A
       ANDB  #%11111100
       LSRB
       ANDA  #3
       PSHS  A
       ADDB  ,S+
       ENDM

*Y ^ CURRENT LINKED MODULE
UNLINK MACR
       LDX   +2,Y *6
       LDU   ,Y   *5
       BEQ   A@   *3
       STX   +2,U *6
A@     STU   ,X   *5
       ENDM

UNLINKX MACR
       LDU   ,X     *5
       BEQ   A@     *3
       LDD   +2,X   *6
       STD   +2,U   *6
A@     STU   [+2,X] *9
       ENDM

*Y ^ USEABLE MEMORY
*X ^ LINKE SPOT (LINKED AFTER)
LINK   MACR
       LDU   ,X
       BEQ   A@
       STY   +2,U
A@     STU   ,Y
       STX   +2,Y
       STY   ,X
       ENDM

NEWLINK MACR
       LDY  ELSTS
     \1BEQ   \0
       UNLINK
       LDX   #WLSTS
       LINK
       CLR   STATUS,Y
       ENDM

NEWLINKA MACR
       LDY   ELSTS
     \1BEQ   \0
       UNLINK
       LDX   #WLSTE
       LINK
       CLR   STATUS,Y
       ENDM

SUBSHL MACR
       LDA   SHIELD
       SUBA  \0
       BCC   A@
       CLRA
A@     STA   SHIELD
       ENDM

ADDSHL MACR
       LDA   SHIELD
       ADDA  \0
       BCC   A@
       LDA   #$FF
A@     STA   SHIELD
       ENDM

ADDSHLA MACR
       ADDA  SHIELD
       BCC   A@
       LDA   #$FF
A@     STA   SHIELD
       ENDM

ADDSCR MACR
       LDD   SCRSTK
       ADDB  \0
       ADCA  #0
       STD   SCRSTK
       ENDM

NXTFRM MACR
       JSR   \0
       ENDM

*U = BLOCKS
*D = PLACE IN BLOCKS
SPRAT  MACR
       LSRA
       LSRA
       LSRA
       LSRA
       ANDA  #%00001110
       LDU   #GRBLK
       LDU   A,U
       LDA   NEWPOS,Y
       ANDA  #%00011111
       ENDM

NOPRN  PULS  X
       STX   TRKDRV,Y
       PULS  Y,D,PC

STDPRN PULS  X
       STX   TRKDRV,Y
       JMP   STDSQD

SQORDERNUM EQU 17
*PERCENT VALUES
SHOOTIT FDB  0
SHTB   FCB   0
SHTR   FCB   0
SHT1   FCB   0
SHT2   FCB   0
SHT3   FCB   0
ATTACKIT FDB 0
GASBUGIT FDB 0
HIT1   FCB   0
HIT2   FCB   0
HIT3   FCB   0
CANSHAKE FCB 0 *0=YES 1=NO
USQUAD FCB   0
SQAVT  FCB   0
*SCORE VALUES FOR A HIT
HBGAS  FCB   9 *A GAS BUG
HBINSQ FCB   3 *SHIP IN SQUAD
HBSSW  FCB   6 *SMALL SHIP
*HIT WITH SHIP:FUEL
HSSB   FCB 2 *SMALL BUG * C
HSBB   FCB 4 *BIG BUG
HSFLG  FCB 6 *FLASHING GAS
HSBULL FCB 4 *BULLETS
HSCOUM FCB 5 *COUM HITS SHIP
*BONUS STUFF
SQAVTM FCB   4 *SQVAT * BONUS
SQHMR  FCB   2 *(H/M RT)*BONUS
LOWSCR BSZ   4
SQDON  FCB   0
CLR1
EXPLEN FCB   0
PCH1   FDB   0
PCH2   FDB   0
SONGP  FDB   0
SONGS  FDB   0
MAYISHOOT FCB 0
FUELPERCENT FCB 0
BONUSTRACK FCB 0
STARSTOP BSZ  3
NOGREEN FCB  0
ATTACKING FCB 0
ATTACKER FCB 0
BUGSINSQUAD FCB 0
ALLBUGSINSQUAD FCB 0
BUGSALIVE FCB 0
BUGWAVES FCB 0
BUGSKILLED FCB 0
BUGSTOTAL FCB 0
ONBONUS FCB 0
REDBUL FDB   0 *0=NO
YELBUL FDB   0 *0=NO
BLUEBUL FDB  0 *0=NO
FIFOP  FDB   0
BUTPRESS FCB 0
NTON   FDB   0
NTLEN  FCB   0
TICKS  FCB   0
OFRAME FCB   0
SEXS   FDB   0
ONMENU FCB   0 *1=YES, 0=NO
DEAD   FCB   0 *0=NO
SHOTS  FDB   0
BHITS
MISSES FDB   0
FUELL  FCB   0
SQDMID FDB   0
SQMVAT FDB   0
BCKGND FDB   0
SHAKER FDB   0
FRGO   FCB   0
SCRSTK FDB   0
SHIPOS FDB   0
HLINE  FCB   0
SHIELD FCB   0
SHLD   FCB   0
RSHLD  FCB   0
SEED   FDB   0
RSEED  FCB   0
BULLETSINAIR FCB 0
SQSYNC FCB   0
SQGO   FCB   0
LSCR   FCB   0
SCR    FCB   0
       FCB   0
       FCB   0
BSTBAS FCB   0
SSTBAS1 FCB  0
SSTBAS2 FCB  0
SSTP1  FCB   0
SSTP2  FCB   0
BUTGO  FCB   0
OBNUM  FCB   0
CLR2


****** FIRQ ******
*465.9 CYCLES
NOISE  STD   DREGN

       LDA   $FF93

NOTE1  LDD   #0
VIB1   ADDD  #0
       STD   VIB1+1
       STA   WAVE1+2

*BRA HERE WHEN ONLY VOICE 1 USED
*SAVES 39 (2340/ 60/SEC)
NOTE2  LDD   #0
VIB2   ADDD  #0
       STD   VIB2+1
       STA   WAVE2+2

*BRA HERE WHEN VOICE 3 NOT USED
*SAVES 18 (1080/ 60/SEC)
NOTE3  LDD   #0
VIB3   ADDD  #0
       STD   VIB3+1
       STA   WAVE3+2

WAVE3  LDB   $C200

WAVE2  ADDB  $C200
WAVE1  ADDB  $C200

       LDA   FXA1+2
FXP1   ADDA  #0
       STA   FXA1+2
FXA1   ADDB  $C200


*********************

*BRA GOES HERE WHEN NOT USED
***SAVES 11 CYCLES (660/ 60/SEC)
*WHEN USED, ADDB $0000 PUT IN
*THIS IS THE BELL SOUND
SPBELL ADDB  $C100
       BGE   C@
LSBELL LDA   #0
       STA   SPBELL+2
MSBELL LDA   #0
       STA   SPBELL+1
       SUBB  #128
       BRA   GOBELL
C@     INC   SPBELL+2
GOBELL

       STB   $FF20

       INC   HLINE

       LDD   #0
DREGN  EQU   *-2
       RTI
*****************


 MSG "GAME DP  @",*-GAMEDP


FSYNC  LDA   #-9
       STA   HLINE
       CLR   FRGO
       LDA   $FF92
       LDU   #$FFB0
       LDX   #8
       LDY   #PALETTES
PAL@   LDD   PALIT-$FFB0,U
       LDA   A,Y
       LDB   B,Y
       STD   ,U++
       LEAX  -1,X
       BNE   PAL@
       LDD   #0
SCRAT  EQU   *-2
BRDR   EQU   *-1
       STA   $FF9F
       STB   $FF9A
       LDD   #0
RNDTIMER EQU *-2
       ADDD  #15263
       STD   RNDTIMER
       DEC   RSEED
       DEC   NTLEN
       RTI

EXPLODE PSHS D,CC
       ORCC  #$50
       LDD   #$C780
       STB   FXP1+1
       STA   FXA1+1
       LDA   #$FF
       STA   EXPLEN
       LDD   #$0100
       STD   PCH1
       LDD   #$3F00
       STD   PCH2
       PULS  D,CC,PC

KABOOM PSHS  D,CC
       LDA   MSBELL+1
       CMPA  #$C5
       BEQ   KA@
       LDA   SPBELL
       CMPA  #$0E
       BNE   O@
KA@    LDD   #$C500
       BRA   G@
BELL   PSHS  D,CC
       LDD   #$C100
G@     ORCC  #$50
       STD   SPBELL+1
       STA   MSBELL+1
       STB   LSBELL+1
       LDA   #$FB
       STA   SPBELL
O@     PULS  D,CC,PC


FIFO
       BSZ   285
GSTAK  FDB   0
       FDB   0
BSTARS BSZ   56
       FDB   0
       FDB   0
       FDB   0
       FDB   0
       BSZ   128
SSTAR  FCB   0
       BSZ   128
       FCB   0
       BSZ   128
       FDB   0
TRNTBL FCB   0
       BSZ   128
       FDB   0
PALIT  BSZ   18
CLR3


GRBLK  FDB   $3536
       FDB   $3637
       FDB   $3738
       FDB   $3839
       FDB   $393A
       FDB   $3A3B
       FDB   $3B35
       FDB   $3535

STBLK  FDB   $3536
       FDB   $3637
       FDB   $3738
       FDB   $3839
       FDB   $393A
       FDB   $3A3B
       FDB   $3B35
       FDB   0


FR1 FCB 54,36,38,32,55,62,37,0
FR2 FCB 55,32,33,36,40,41,9,8,1
    FCB 4,54,0
FR3 FCB 8,51,36,1,2,4,36,32,38
    FCB 39,11,13,15,36,38,39,54
    FCB 55,44,45,40,47,37,36,63
    FCB 62,0

FLSH   FCB   54,36,52,32
       FCB   44,52,45,40
       FCB   12,32,4,32
       FCB   32,32,5,5
       FCB   4,4,4,4,4
FLSHE  FCB   0

SONGTAB1
 FDB LOAN,BUMBLE,STORM,0
 FDB SONGTAB2
SONGTAB2
 FDB BUMBLE,LOAN,STORM,0
 FDB SONGTAB1

*SHOOT
ESHT   LDA   ATTACKER
       STA   ATTACKING
       CLR   ATTACKER
       LDA   ONBONUS
       BNE   ?RTS
       LDA   ONMENU
       BNE   ?RTS
       JSR   ARB
       SUBD  SHOOTIT
       BHS   A@
       NEWLINK (?RTS)
       CLR   STATUS,Y
       LDD   #EXSHT
       STD   TRKDRV,Y
*ATTACK
A@     LDA   ALLBUGSINSQUAD
       STA   BUGSINSQUAD
       BNE   NALL@
       LDA   ATTACKING
       CMPA  #8
       BHI   B@
       LDA   OBNUM
       CMPA  #5
       BLO   ATK@
       BSR   ARB
       SUBD  ATTACKIT
       BHS   B@
ATK@   NEWLINK (?RTS)
       CLR   STATUS,Y
       LDD   #ATTACK
       STD   TRKDRV,Y
B@     LDA   OBNUM
       CMPA  #4
       BLS   ?RTS
       BSR   ARB
       SUBD  GASBUGIT
       BHS   ?RTS
       LDB   SQAVT
       CLRA
       SUBD  SEXS
       BLO  ?RTS
       NEWLINKA (?RTS)
       CLR   STATUS,Y
       LDD   #CLBUG
       STD   TRKDRV,Y
       RTS
NALL@  CLR   ALLBUGSINSQUAD
       RTS

ARB    LEAS  -2,S
       LDA   RSEED
       ADDA  #107
       STA   RSEED
       LDA   SEED+1
       LDB   #$55
       MUL
       STD   ,S
       LDA   SEED+1
       LDB   #$62
       MUL
       ADDB  ,S
       STB   ,S
       LDA   SEED
       LDB   #$55
       MUL
       ADDB  ,S
       STB   ,S
       LDD   #13849
       ADDD  ,S++
       STD   SEED
       ADDD  RNDTIMER
       ADDA  RSEED
       RTS

DZERO  PSHS  Y,D,X,U
       LEAY  +256,Y
       LDD   #$000F
       STD   ,Y
       LDU   #$FFF0
       STU   +2,Y
       LEAY  +256,Y
       LDB   #$FF
       STD   ,Y
       STD   +2,Y
       LEAY  +256,Y
       LDX   #$00FF
       STX   ,Y
       LDA   #$0F
       STD   +2,Y
       LEAY  +256,Y
       STX   ,Y
       LDA   #$FF
       STD   +2,Y
       LEAY  +256,Y
       LDA   #$F0
       STX   ,Y
       STD   +2,Y
       LEAY  +256,Y
       STX   ,Y
       STX   +2,Y
       LEAY  +256,Y
       STU   +2,Y
       LDU   #$000F
       STU   ,Y
       PULS  X,Y,U,D,PC

SETCOL JSR   COPY
       FDB   PALIT
       FCB   16
       FCB   0,54,52,34
       FCB   10,25,59 *BLUE
       FCB   32,36,60 *RED
       FCB   2,16,18  *GREEN
       FCB   54,53,63
       RTS

MENUCOLORS
*A=YELLOW, B=RED, F=WHITE
       LDD   #$3624
       STD   PALIT+$A
       RTS

GAME   ORCC  #$50
*Y,U = LOW SCORE
       LDA   #$3F
       LEAS  GSTAK,PCR
       STA   $FFA7
       LDS   #GSTAK
       LDA   #$E0
       TFR   A,DP
       JMP   A@
A@     STY   LOWSCR
       STU   LOWSCR+2
       STB   SQDON
       JSR   VSYNC
       LDX   #$FFB0
       LDA   #16
C@     CLR   ,X+
       DECA
       BNE   C@
       LDA   #%01111110
       STA   $FF99
       LDB   #$08  *IRQ *$20
       STB   $FF92
       LDB   #$20  *FIRQ *$08
       STB   $FF93
       CLR   $FF9A
*      LDD   #$D000 *$68000
       LDD   #$D620 *D620
       STD   $FF9D
       LDA   #24+128
       STA   $FF9F
       STA   SCRAT
***CLEAR $79000-$6A000
       LDD   #$3C08
       LDU   #0
       LDX   #$1200
       BRA   E@
D@     LDX   #$2000
E@     STA   $FFA0
F@     STU   ,--X
       CMPX  #0
       BHI   F@
       DECA
       DECB
       BNE   D@
***CLEAR VARS
       LDX   #CLR1
I@     STB   ,X+
       CMPX  #CLR2
       BNE   I@
       LDX   #FIFO
J@     STB   ,X+
       CMPX  #CLR3
       BNE   J@
       DO    WRITCS
       FCB   CHMODE
       FDB   256
       FCB   CHCOL
       FDB   $FF
       FCB   GOTOXY
       FDB   224*256+48
 FCC "SCORE:000000  FUEL:",0
       JSR   SETCOL
       LDX   #FR1
       STX   FIRE1
       LDX   #FR2
       STX   FIRE2
       LDX   #FR3
       STX   FIRE3
       LDX   #FLSHE
       STX   BCKGND
       LDX   #SHAKEND
       STX   SHAKER
       LDA   #-9
       STA   HLINE
       LDA   #1
       STA   MAYISHOOT
       STA   SHLD
       STA   NOGREEN
       STA   STARSTOP
       LDD   #4
       STD   SSTBAS1
       LDD   #2
       STD   SSTP1
       LDD   #$C200
       STD   FXA1+1
       LDD   #0
       STA   FXP1+1
       STA   OBNUM
       STA   SQGO
       STA   SQSYNC
       STD   SCRSTK
       STD   SCR
       STA   SCR+2
       STA   LSCR
       STA   SQSYNC
       STA   $FF20
       STD   SEED
       STA   RSEED
       STA   BULLETSINAIR
       STD   RNDTIMER
       LDA   #130
       STA   SHIELD
       STA   RSHLD
       LDD   #$E00+(FSYNC!.$FF)
       STD   [$FFF8] *FIRQ
       LDD   #$E00+(NOISE!.$FF)
       STD   [$FFF6] *IRQ
       LDD   #$3DC $3DC
       STD   $FF94
       LDD   #$8000
       STD   SHIPOS
       LDA   #$3E
       STA   $FFA6
       CLR   NTLEN
       LDX   #SONGTAB1
       LDA   PARAMT
       BPL   SP@
       LDX   #SONGTAB2
SP@    LDU   ,X++
       STX   SONGP
       STU   SONGS
       STU   NTON
       LDU   #TRNTBL
       CLRB
K@     PSHS  B
       TFR   B,A
       ANDB  #$0F
       LSRA
       LSRA
       LSRA
       LSRA
       LDX   #0
L@     PSHS  B
       CMPA  ,S+
       BEQ   M@
       LEAX  +1,X
       INCA
       ANDA  #$0F
       BRA   L@
M@     LDA   ,S
       CMPX  #0
       BNE   N@
       STB   A,U
       BRA   P@
N@     CMPX  #8
       BLO   O@
       INCB
       SKIP1
O@     DECB
       ANDB  #$0F
       STB   A,U
P@     PULS  B
       INCB
       BNE   K@
       JSR   BELL
       JSR   VSYNC
       ANDCC #$AF
       JMP   INITLIST
*END OF INIT

FRINI  JSR   FRPAL
       LDA   #%01111111
       STA   $FF02
       LDA   $FF00
       ANDA  #%00001000 *BREAK
       BEQ   PAUSE
A@     JSR   FRFUEL
       RTS

PAUSE  ORCC  #$50
       LDA   $FF02
S@     LDA   $FF03
       BPL   S@
     IFEQ  PAUSECLEAR
       LDX   #$FFB0
       LDD   #$000F
D@     STA   ,X+
       DECB
       BNE   D@
     ENDC
       LDD   #$3835
       STD   $FFA0
       LDX   #PSGET
       JSR   PSCOPY
     IFEQ  PAUSECLEAR
       DO    WRITCS
       FCB   CHCOL
       FDB   $00FF
       FCB   GOTOXY
       FDB   96*256+60+48
 FCC "PAUSE MODE",0
       JSR   SLOW
       DO    WRITCS
       FCB   GOTOXY
       FDB   106*256+22+48
 FCC 'PRESS FIRE BUTTON '
 FCC 'TO CONTINUE',0
       JSR   SLOW
       DO    WRITCS
       FCB   GOTOXY
       FDB   116*256+38+48
 FCC 'PRESS "BREAK" TO QUIT',0
     ENDC
       LDX   #PSOR
       BSR   PSCOPY
B@     LDB   #$FF
       STB   $FF02
       LDB   $FF00
       ANDB  #%00000001
       BEQ   C@ *BUTTON PRESSED
*BREAK TEST
       LDB   #%11111011
       STB   $FF02
       LDB   $FF00
       ANDB  #%01000000
       BNE   B@
*BREAK HIT
       LDA   #$3C
       STA   $FFA5
       JMP   $B209
*UNPAUSE
C@     STB   BUTGO
       JSR   VSYNC
       ANDCC #%11101111
       JSR   VSYNC
       BSR   SLOW
       LDY   #70
       LDX   #PSPUT
       LDU   #$2000
       BSR   PSBLCK
       BSR   SLOW
       BSR   PSBLCK
       BSR   SLOW
       BSR   PSBLCK
       BSR   SLOW
       LDA   $FF02
A@     LDA   $FF03
       BPL   A@
       ANDCC #$AF
       JSR   FRPAL
       JMP   FRINI

SLOW   LDB   #30
A@     JSR   VSYNC
       DECB
       BNE   A@
       RTS

PSCOPY LDU   #$2000
       LDY   #70
       LDA   #3
A@     BSR   PSBLCK
       DECA
       BNE   A@
       RTS
PSBLCK LDB   #10
C@     BSR   PSLINE
       LEAY  +136,Y
       DECB
       BNE   C@
       RTS
PSLINE PSHS  D
       LDA   #120
D@     JSR   ,X *EXEC COMMAND
       DECA
       BNE   D@
       PULS  D,PC
PSGET  LDB   ,Y+
       STB   ,U+
       RTS
PSOR   LDB   ,Y
       ORB   ,U+
       STB   ,Y+
       RTS
PSPUT  LDB   ,U+
       STB   ,Y+
       RTS

*PALETTES ARE SET BY INTERUPT.
*THIS ONLY SELECTS THE COLORS
*FOR THE NEXT INTERUPT.
FRPAL  JSR   ESHT
       LDB   FRGO
       BEQ   E@ *NO TIME FOR SCR
       JSR   FRSCR
       LDB   SCRSTK
       BEQ   D@
       LDB   FRGO
       BEQ   E@
       JSR   FRSCR
       LDB   FRGO
       BEQ   E@
       JSR   FRSCR
       LDB   FRGO
       BEQ   E@
       JSR   FRSCR
*WAIT FOR FRAME SYNC
D@     LDB   FRGO
       BNE   D@
E@     LDA   #1 *RESET FRAME
       STA   FRGO
       LDA   OFRAME
       BMI   NOFIRE@
       LDX   #0
FIRE1  EQU   *-2
       LDA   ,X+
       BNE   A@
       LDX   #FR1
       LDA   ,X+
A@     STA   PALIT+1
       STX   FIRE1
       LDX   #0
FIRE2  EQU   *-2
       LDA   ,X+
       BNE   B@
       LDX   #FR2
       LDA   ,X+
B@     STA   PALIT+2
       STX   FIRE2
       LDX   #0
FIRE3  EQU   *-2
       LDA   ,X+
       BNE   C@
       LDX   #FR3
       LDA   ,X+
C@     STA   PALIT+3
       STX   FIRE3
*DO SHAKE
NOFIRE@ LDX   SHAKER
       LDA   ,X+
       BEQ   I@
       STX   SHAKER
       STA   SCRAT
*DO BACKGROUND
I@     LDX   BCKGND
       LDA   ,X+
       BEQ   F@
       STX   BCKGND
F@     STA   PALIT
       STA   BRDR

*DO BELL SOUND
       LDA   LSBELL+1
       SUBA  #8
       BNE   A@
       LDD   #$E00+(GOBELL!.$FF)
       STD   SPBELL
       BRA   B@
A@     STA   LSBELL+1
B@


       LDA   SHIELD
       CMPA  RSHLD
       BHI   G@
       BNE   L@
       STA   RSHLD
       BRA   Z@
L@     STA   RSHLD
       LDX   #FLSH
       STX   BCKGND
       JSR   KABOOM
*DO SHAKE & CRASH (IF OK)
       LDA   CANSHAKE
       BEQ   Z@
       LDX   #SHAKE
       STX   SHAKER
       BRA   Z@
*FUEL GOES UP - MAKE DING SOUND
G@     STA   RSHLD
       JSR   BELL
Z@
******************
*DO FIRE SOUND
       LDA   FXP1+1
       BEQ   OUT@
       BMI   A@
       SUBA  #4
       SKIP1
A@     INCA
       STA   FXP1+1
OUT@

*EXPLOSION, PCH (1-2) = PITCHES
       LDA   EXPLEN
       BEQ   MU@
       LDB   #$3D
       STB   $FFA4
       CLR   NTLEN
       CMPA  #$85
       BNE   WN@
       STA   FXP1+1
WN@    DEC   EXPLEN
       LDU   #PITCH
       LDX   #NOTES
*DO NOTE 3
       CMPA  #224
       BLS   N1@
       LDY   $1F*2,U
       STY   ,X++
       LDB   #$C6 *RNDISH
       STB   ,X+
*DO NOTE 1
N1@    CMPA  #30
       BLS   N2@
       LDD   PCH1
       ADDD  #$3F
       STD   PCH1
       LSLA
       LDD   A,U
       STD   ,X++
       LDA   #$C2 *NORMAL
       STA   ,X+
*DO NOTE 2
N2@    LDD   PCH2
       ADDD  #$FFC1
       STD   PCH2
       LSLA
       LDD   A,U
       STD   ,X++
       LDA   #$C6 *RNDISH
       STA   ,X+
       CLR   ,X+
       CLR   ,X
       LDX   #NOTES
       JMP   ENSND
*MUSIC
MU@    LDA   NTLEN
       BPL   ?RTS
       LDA   #$3D
       STA   $FFA4
A@     LDX   NTON
       LDA   ,X
       BNE   B@
       LDX   SONGS
       LDA   ,X
B@     LSRA
       LSRA
       STA   NTLEN
       LDA   ,X+
       LDY   #PITCH
       LDU   #NOTES
*Y ^ NOTE PITCHES
*X ^ SONGS
*U ^ NOTES
       ANDA  #3
       BEQ   P@
       STA   ,-S
C@     LDB   ,X+
       CLRA
       LSLB
       ROLA
       LSLB
       ROLA
       LSRB
       ADDA  #$C2
       STA   +2,U
       LDD   B,Y
       STD   ,U
       LEAU  +3,U
       DEC   ,S
       BNE   C@
       PULS  A
P@     STX   NTON
       LDD   #0
       STD   ,U
       LDX   #NOTES

****************************

*X ^ (PITCH, WAVE...)
ENSND  ORCC  #$50
       LDD   #$CCFB *LDD/ADDB

*NOTE 1 IS ALWAYS AN LDD
       STA   NOTE2
       STA   NOTE3

       STB   WAVE1
       STB   WAVE2
*WAVE 3 IS ALWAYS A LDB

*DO NOTE 1
       LDU   ,X++
       STU   NOTE1+1
       BEQ   N1E@
       LDA   ,X+
       STA   WAVE1+1
*DO NOTE 2
       LDU   ,X++
       BNE   A@ *CONTINUE
*NO NOTE IN NOTE 2
N1E@   LDD   #$E00+(WAVE1!.$FF)
       STD   NOTE2
       LDB   #$F6 *LDB
       STB   WAVE1
       ANDCC #$AF
       RTS
A@     STU   NOTE2+1
       LDA   ,X+
       STA   WAVE2+1
*DO NOTE 3
       LDU   ,X++
       BNE   B@ *CONTINUE
*NO NOTE IN NOTE 3
       LDD   #$E00+(WAVE2!.$FF)
       STD   NOTE3
       LDB   #$F6
       STB   WAVE2
       ANDCC #$AF
       RTS
B@     STU   NOTE3+1
       LDA   ,X+
       STA   WAVE3+1
       ANDCC #$AF
       RTS


NOTES
       BSZ   11


FRSCR  LDD   #$3F3C *SWI & MENU
       STD   $FFA4
       LDD   SCRSTK
X@     SUBD  #1
       BCS   ?RTS
       STD   SCRSTK
       LDA   #1
       ADDA  SCR+2
       DAA
       STA   SCR+2
       BCC   Y@
       LDA   #0
       ADCA  SCR+1
       DAA
       STA   SCR+1
       BCC   Y@
       LDA   #0
       ADCA  SCR
       DAA
       STA   SCR
*FAST TEST
Y@     LDY   #$A000+48+44
       LDB   SCR+2
       ANDB  #$0F
       BEQ   B@
       ADDB  #48
       JSR   PR1CH
       BRA   G@
B@     JSR   DZERO
       LDY   #$A000+48-4+44
       LDB   SCR+2
       ANDB  #$F0
       BEQ   C@
       LSRB
       LSRB
       LSRB
       LSRB
       ADDB  #48
       JSR   PR1CH
       BRA   G@
C@     JSR   DZERO
       LDY   #$A000+48-8+44
       LDB   SCR+1
       ANDB  #$0F
       BEQ   D@
       ADDB  #48
       JSR   PR1CH
       BRA   G@
D@     JSR   DZERO
       LDY   #$A000+48-12+44
       LDB   SCR+1
       ANDB  #$F0
       BEQ   E@
       LSRB
       LSRB
       LSRB
       LSRB
       ADDB  #48
       JSR   PR1CH
       BRA   G@
E@     JSR   DZERO
       LDY   #$A000+48-16+44
       LDB   SCR
       ANDB  #$0F
       BEQ   F@
       ADDB  #48
       JSR   PR1CH
       BRA   G@
F@     JSR   DZERO
       LDY   #$A000+48-20+44
       LDB   SCR
       LSRB
       LSRB
       LSRB
       LSRB
       ADDB  #48
       JSR   PR1CH
G@     RTS

*DO SHIELD
FRFUEL LDA   #$3C
       STA   $FFA5
       LDA   SHLD
       CMPA  SHIELD
       BEQ   I@
       BLO   J@
       DECA
       SKIP1
J@     INCA
I@     STA   SHLD
       LDX   #$A200+48+20*4
       LSRA
       LEAX  A,X
       BCC   H@
       LDA   #$FF
       SKIP2
H@     LDA   #$F0
       CLRB
       STD   ,X
       STD   +2*256,X
       STD   +4*256,X
       LDA   SHLD
       BNE   ?RTS
       CLR   ,X
       CLR   +2*256,X
       CLR   +4*256,X
       IFEQ  INVINCIBLE
       JMP   SBLOW
       ELSE
       RTS
       ENDC

SHAKE
 FCB 152,157,159,160,158,156
 FCB 152,149,147,147,147,148
 FCB 150,152,154,155,155,154
 FCB 153,151,150,149,149,149
 FCB 150,151,152,153,154,154
 FCB 153,152,151,150,150,150
 FCB 150,151,152,153,153,153
 FCB 153,152,151,151,150,150
 FCB 150,151,151,152,152,153
 FCB 153,152,152,151,151,150
 FCB 150,151,151,152
SHAKEND
 FCB 0