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Snowplow.asm
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2984 lines (2984 loc) · 39.4 KB
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;SAVE#D:SNOWA.PT1
;-------------------
; part 1 of the game
;
; by: Barry Kolbe
;
;-------------------
.OPT NOLIST
;
;page zero variables
;
DRY = $82
PXP = $83 ;2byter
PYP = $85 ; "
ADD = $87
HMV = $88
CURCHR = $89
VERT = $8A
EADD = $8B
EHOLD = $8C
EYX = $8D
EYY = $8E
ICY = $8F
ICX = $90
VTIME = $91
VFLG = $92
XSP = $93
YSP = $94
RAND = $95
ICNT = $96
DATA = $97
UNIQUE = $98
FTIME = $99 ;7 bytes
CARTIM = $A0 ;6 bytes
RMTIM = $A6 ;6 bytes
ROADC = $AC ;2 bytes
ROADG = $AE ; "
CNT = $B0
SHD = $B1
MAPFLG = $B2
FUEL = $B3 ;3 bytes
LIVES = $B6
DIRF = $B7
DIRECT = $B8
CARCNT = $B9
ICEON = $BA
Y1 = $BB
Y2 = $BC
ICEDIR = $BD
IDECNT = $BE
LEVEL = $BF
FULK = $C0
ICTL = $C1
ICTH = $C2
ICESPEED = $C3
THOUS = $C4
SPSND = $C5
IFLAG = $C6
IISY = $C7
IIY3 = $C8
COUNT = $C9 ;these are
IL = $CB
TL = $CB ;all
JL = $CD
BFL = $CD
INDR = $CB ;2 bytes
IND2 = $CD
FOFS = $CF
YH = $D0
XD1 = $D1
XH = $D2
ICECNT = $D3
SCRS = $D4 ;6 bytes
FULX = $DA ;6 bytes
FULY = $E0 ;6 bytes
CARX = $E6 ;4 bytes
CARY = $EA ;4 bytes
OFFSCN = $EE ;2 bytes
SLENGTH = $F0
EDM = $F1 ;2
SXP = $F3
SYP = $F4
;
;OS equates
;
CIOV = $E456
ICCOM = $0342
ICBAL = $0344
ICBAH = $0345
ICBLL = $0348
ICBLH = $0349
AUX1 = $034A
AUX2 = $034B
SETVBV = $E45C
XITVBV = $E462
RANDOM = $D20A
RTCLOK = $14
CONSOL = $D01F
EOL = $9B
SEOL = $BB
PCHR = 54
;
COLOR0 = $02C4
COLOR1 = $02C5
COLOR2 = $02C6
COLOR3 = $02C7
COLOR4 = $02C8
SDLSTL = $0230
CH = $02FC
;
STICK = $0278
STRIG = $0284
HPOSP0 = $D000
HPOSM0 = $D004
HSCROL = $D404
VSCROL = $D405
HITCLR = $D01E
P0PL = $D00C
P1PL = $D00D
;
;memory usage
;
SCNMEM = $9000
PMB = $8000
SET = $8C00
MYPMB = $8400
MSMEM = PMB+$0300
P0MEM = MYPMB
P1MEM = MYPMB+$0100
P2MEM = MYPMB+$0200
P3MEM = MYPMB+$0300
CHSET = $8C00
GOVER = $9B00
TXTWIN = $8B00
SCLN = TXTWIN+20
CHRLN1 = TXTWIN+40
SC2 = SCNMEM+128
SC3 = SC2+128
SC4 = SC3+128
SC5 = SC4+128
SC6 = SC5+128
SC7 = SC6+128
SC8 = SC7+128
SC9 = SC8+128
SC10 = SC9+128
SC11 = SC10+128
BCKUP = $7FC0
SET2 = $7D00
SCRLMEM = $7C00
;credits @ $7b00
;
;display list interrupt
;
*= PMB
DLI PHA
DIC LDA #2
STA $D40A
STA $D01A
PLA
RTI
;
;character set
;
*= $8C00
.INCLUDE #D:SNOW.PT5
;
*= TXTWIN
.SBYTE " FUEL 150 PLOWS "
.SBYTE "3 SCORE "
.SBYTE "000000 "
;
*= GOVER
.SBYTE " SNOWFLAKES "
.SBYTE "WIN press "
.SBYTE "START "
;
;display lists ;intro first
;then game board
;
*= $7F00
IDLST .BYTE $70,$70,$70,$70
.BYTE $70,$70,$70,$42
.WORD SNOWMEM
.BYTE $02,$70,$70,$70,$02
.BYTE $02,$70,$70,$70,$70
.BYTE $57
LMS .WORD SCRLMEM
.BYTE $70,$70,$70,$70,$46
.WORD TOPSCORE
.BYTE $41
.WORD IDLST
;
*= $7F80
DL1 .BYTE $70,$70,$70
.BYTE $42
.WORD SNOWMEM
.BYTE 2
.BYTE $75
SL1 .WORD SCNMEM
.BYTE $75
.WORD SC2
.BYTE $75
.WORD SC3
.BYTE $75
.WORD SC4
.BYTE $75
.WORD SC5
.BYTE $75
.WORD SC6
.BYTE $75
.WORD SC7
.BYTE $75
.WORD SC8
.BYTE $75
.WORD SC9
.BYTE $75
.WORD SC10
.BYTE $D5
.WORD SC11
.BYTE $46
TMESS .WORD TXTWIN
.BYTE 6,$41
.WORD DL1
;
;start of program
;
*= $4000
;
;save the display list
;for next levels
;
BEGIN LDY #50
MDL LDA DL1,Y
STA BCKUP,Y
DEY
BPL MDL
LDA #>CHSET ;new chrset
STA 756
JSR SETPMG ;player init
;
LDX #>VBLNK ;set vbi
LDY #<VBLNK
LDA #7
JSR SETVBV
LDA #0
STA IFLAG ;intro flag
;
;begin new level
;
NEWBEG LDA #0
STA DIRF
STA MAPFLG
JSR GETDIR
JMP NEWB
NDIRC JSR CLOSE6
;
NEWB JSR INIT
JSR REPLAY
LDA #3
STA LIVES
LDA #0
STA ICEON
JSR SHOLIV
NLEVL JSR STARTI
JSR FIGLEV
JSR RESFUL
JSR DSPFUL
JSR REPLAY
JSR CLRPM
LDA DIRF
BNE DROK
MAP2 LDA MAPFLG ;intern map
BNE DROK
LDA #1
STA MAPFLG
JSR UNCOM
JMP SKP
DROK JSR GETFIL
JSR LOADMP
SKP JSR FNDFUL
JSR FNDCRS
JSR CNTRDS
JSR COPYDL
JSR SETSCN
LDA #$0B
STA DIRECT
JSR DEFPLR
LDA #1
STA VFLG
;
;main loop
;
MAIN LDA CONSOL
CMP #6
BNE MN2
JMP STKEY
MN2 LDA STICK
STA DIRECT
JSR DEFPLR
STA HITCLR
JSR MOVPLR
JSR REMOVE
LDA 644
BNE NTRG
JSR JMPEDG
NTRG JSR ICESND
LDA P0PL
CMP #12
BCS OUCH
LDA P1PL
CMP #12
BCS OUCH
LDA ROADG+1
CMP ROADC+1
BNE KL
LDA ROADG
CMP ROADC
BNE KL
JSR WAITSM
JMP NLEVL
KL LDA FUEL
ORA FUEL+1
ORA FUEL+2
BNE KK
OUCH STA HITCLR
JSR REMP23
JSR SPIN
JSR GRESET
STA HITCLR
JSR DELAY
JMP KK
OOPS JMP GAMOVR
KK LDA LIVES
BEQ OOPS
LDA CH
CMP #$FF
BEQ NOPAUS
JSR PAUSE
NOPAUS JMP MAIN
;
;set pmg
;
SETPMG LDA #62
STA 559
LDA #17 ;5th enable
STA 623
LDA #3
STA 53277
LDA #>PMB
STA 54279
LDA #$28 ;yellow
STA 704
LDA #6 ;black
STA 705
LDA #$A6
STA 706
STA 707
LDA #$80
STA PXP
LDA #$70
STA PYP
LDA #1
STA 53258
STA 53259
RTS
;
;clear pm area
;
CLRPM LDY #$FF
LDA #0
CPM STA P0MEM,Y
STA P1MEM,Y
STA P2MEM,Y
STA P3MEM,Y
STA MSMEM,Y
DEY
CPY #$FF
BNE CPM
RTS
;
;define plrs
;
DEFPLR LDX #3
LDA DIRECT
DF1 CMP DIRTAB,X
BEQ DFOK
DEX
BPL DF1
RTS
DFOK LDA PD0L,X
STA JL
LDA PD0H,X
STA JL+1
LDA PD1L,X
STA IL
LDA PD1H,X
STA IL+1
TXA
PHA
LDA PYP
STA Y1
CLC
ADC YTB,X
STA PYP+1
STA Y2
TAY
LDA #0
STA P1MEM-1,Y
LDY #0
DFP LDA (JL),Y
LDX Y1
STA P0MEM,X
LDA (IL),Y
LDX Y2
STA P1MEM,X
INY
INC Y1
INC Y2
CPY #16
BNE DFP
LDX Y2
STA P1MEM,X
LDX PXP
STX HPOSP0
PLA
TAX
LDA PXP
CLC
ADC XTB,X
STA PXP+1
STA HPOSP0+1
RTS
;
DIRTAB .BYTE 11,7,14,13
XTB .BYTE $FF,$01,$00,$00
YTB .BYTE $00,$00,$FF,$01
;
;player definitions & tables
;
PD0L .BYTE <P0D1,<P0D2,<P0D3,<P0D4
PD0H .BYTE >P0D1,>P0D2,>P0D3,>P0D4
PD1L .BYTE <P1D1,<P1D2,<P1D3,<P1D4
PD1H .BYTE >P1D1,>P1D2,>P1D3,>P1D4
P0D1 .BYTE $00,$00,$00,$FF
.BYTE $FF,$76,$76,$76
.BYTE $76,$76,$76,$FF
.BYTE $FF,$00,$00,$00
P0D2 .BYTE $00,$00,$00,$FF
.BYTE $FF,$6E,$6E,$6E
.BYTE $6E,$6E,$6E,$FF
.BYTE $FF,$00,$00,$00
P0D3 .BYTE $00,$66,$66,$7E
.BYTE $7E,$7E,$7E,$7E
.BYTE $7E,$66,$66,$66
.BYTE $7E,$7E,$66,$00
P0D4 .BYTE $00,$66,$7E,$7E
.BYTE $66,$66,$66,$7E
.BYTE $7E,$7E,$7E,$7E
.BYTE $7E,$66,$66,0
;
P1D1 .BYTE $00,$AA,$AA,$80
.BYTE $80,$84,$84,$84
.BYTE $84,$84,$84,$80
.BYTE $80,$AA,$AA,$00
P1D2 .BYTE $00,$FD,$FD,$01
.BYTE $01,$61,$61,$61
.BYTE $61,$61,$61,$01
.BYTE $01,$FD,$FD,$00
P1D3 .BYTE 0,$FF,$FF,$00
.BYTE $99,$99,$18,$18
.BYTE $99,$99,$18,$18
.BYTE $99,$99,$00,$00
P1D4 .BYTE $00,$00,$81,$99
.BYTE $18,$18,$99,$99
.BYTE $18,$18,$99,$99
.BYTE $00,$FF,$FF,$00
;
;delay
;
LDL LDY #19
BNE DLN
DELAY LDY #7
DLN JSR WAIT
DEY
BNE DLN
RTS
;
;initialize
;
;set up 128 table
INIT LDY #0
LDA #<SCNMEM
STA M128L
LDA #>SCNMEM
STA M128H
TLP LDA M128L,Y
CLC
ADC #128
STA M128L+1,Y
LDA M128H,Y
ADC #0
STA M128H+1,Y
INY
CPY #33
BNE TLP
;
LDX #7 ;score & fuel
LDA #$10 ;IC $10
SCF STA SCRS,X
DEX
BPL SCF
STA THOUS
JSR RESFUL
LDA #3 ;set lives
STA LIVES
LDA #$13
STA TXTWIN+16
LDA #$60
STA ICECNT
LDA #$FF
STA LEVEL
RTS
;
CLRTAB .BYTE $D8,$44,$0A,$46,$00
;
STSCRL LDA #>SL1
STA JL+1
LDA #<SL1
STA JL
RTS
;
;get scn pos
;
WHER LDY DRY
WHERE LDA M128L,Y
STA JL
LDA M128H,Y
STA JL+1
RTS
;
;shadow scrols
;
SMX .BYTE 22 ;pos on scrn
SMY .BYTE 4
;
;move
;
SCROLL LDA DIRECT
;
MMR CMP #7 ;rt?
BNE MML
JSR LOOKR
BCC RA1
RTS
RA1 LDA SXP
CMP #83
BCC HO
RTS
HO LDA #1
STA VERT
JSR PLWSND
KB LDA #1
STA ADD
JSR CORSH
INC SMX
INC SXP
LDX #3
KA STX HSCROL
JSR WAIT
JSR TRACKR
DEX
BPL KA
DEC VERT
LDA VERT
BPL KB
FULOUT JSR SFUEL
JSR OFF2
JSR CKFTIM
RTS
;
MML CMP #11
BNE MUP
JSR LOOKL
BCC LA1
RTS
LA1 LDA SXP
BNE HQ
RTS
HQ LDA #1
STA VERT
JSR PLWSND
KD LDX #0
KC STX HSCROL
JSR WAIT
JSR TRACKL
INX
CPX #4
BNE KC
LDA #$FF
STA ADD
LDX #0
STX HSCROL
JSR CORSH
DEC SXP
DEC SMX
DEC VERT
LDA VERT
BPL KD
JMP FULOUT
;
;coarse h scrol
;
CORSH LDY #0
CSA LDA SL1,Y
CLC
ADC ADD
STA SL1,Y
INY
INY
INY
CPY #33
BNE CSA
RTS
;
;up
;
MUP CMP #14
BNE MDN
JSR LOOKU
BCC UA1
RTS
UA1 LDA SYP
BEQ NOM
JSR PLWSND
LDA #$FF
STA ADD
JSR CORSV
DEC SYP
DEC SMY
LDX #15
U1 STX VSCROL
JSR WAIT
JSR TRACKU
DEX
BPL U1
LDA #0
STA VSCROL
JMP FULOUT
RTS
;
;down
;
MDN CMP #13
BNE NOM
JSR LOOKD
BCC DA1
RTS
DA1 LDA SYP
CMP #9
BCC D1
RTS
D1 JSR PLWSND
LDX #0
D2 STX VSCROL
JSR WAIT
JSR TRACKU
INX
CPX #16
BNE D2
LDX #0
STX VSCROL
LDA #1
STA ADD
JSR CORSV
INC SYP
INC SMY
JMP FULOUT
NOM RTS
;
;coarse vrt scrl
;
CORSV LDA ADD
BMI CSV
LDY #0
CVL LDA SL1,Y
CLC
ADC #$80
STA SL1,Y
INY
LDA SL1,Y
ADC #0
STA SL1,Y
INY
INY
CPY #33
BNE CVL
RTS
;
CSV LDY #0
CVP LDA SL1,Y
SEC
SBC #$80
STA SL1,Y
INY
LDA SL1,Y
SBC #0
STA SL1,Y
INY
INY
CPY #33
BNE CVP
RTS
;
;wait a jiffy
;
WAIT LDA #0
STA $14
WW2 LDA $14
BEQ WW2
RTS
;
;fine scrl plr
;
MOVPLR LDA DIRECT
CMP #7
BNE MLL
LDA PXP
CMP #$7C
BCC GOR
LDA SXP
CMP #83
BCS GOR
JMP MOUT
GOR LDA PXP
CMP #$C8
BCS MVRET
JSR LOOKR
BCC GOR1
RTS ;nope
GOR1 JSR PLWSND
LDY #7
RL1 INC PXP
LDX PXP
STX HPOSP0
INC PXP+1
LDX PXP+1
STX HPOSP0+1
JSR WAIT
JSR TRACKR
DEY
BPL RL1
INC SMX
INC SMX
JMP FULOUT
MOUT JSR SCROLL
MVRET RTS
;
MLL CMP #11
BNE MDD
JSR LOOKL
BCC GOL2
RTS
GOL2 LDA PXP
CMP #132 ;124+8
BCS GOL1
LDA SXP
BNE MOUT
GOL LDA PXP
CMP #$30
BEQ MVRET
BCC MVRET
GOL1 JSR PLWSND
LDY #7
LL1 DEC PXP
LDX PXP
STX HPOSP0
DEC PXP+1
LDX PXP+1
STX HPOSP0+1
JSR WAIT
JSR TRACKL
DEY
BPL LL1
DEC SMX
DEC SMX
JMP FULOUT
;
MDD CMP #13
BNE MUU
JSR LOOKD
BCC GD3
RTS
GD3 LDA PYP
CMP #$60
BCC GDN
LDA SYP
CMP #9
BCS GDN
JMP MOUT
GDN LDA PYP
CMP #$C0
BCS MVRET
LDA #15
STA VERT
JSR PLWSND
GD2 LDA PYP
STA Y1
LDA PYP+1
STA Y2
TAY
LDA #0
STA P1MEM,Y ;eras top
LDX #15
GD1 LDY Y1
LDA P0MEM+15,Y
STA P0MEM+16,Y
LDY Y2
LDA P1MEM+15,Y
CMP #$18
BNE FOA
LDA #$99
BNE FOB
FOA CMP #$99
BNE FOB
LDA #$18
FOB STA P1MEM+16,Y
DEC Y1
DEC Y2
DEX
BPL GD1
INC PYP
INC PYP+1
JSR WAIT
DEC VERT
LDA VERT
BPL GD2
INC SMY
JMP FULOUT
;
;
MUU CMP #14
BEQ MU3
GU4 JMP MVRET
MU3 JSR LOOKU
BCC MU4
RTS
MU4 LDA PYP
CMP #$70
BCS GUU
LDA SYP
BEQ GUU
JMP MOUT
GUU LDA PYP
CMP #$30
BNE GU5
JMP MOUT
GU5 JSR PLWSND
LDA #15
STA VERT
GU2 LDY PYP
LDX #15
GU1 LDA P0MEM,Y
STA P0MEM-1,Y
LDA P1MEM,Y
CMP #$18
BNE FOC
LDA #$99
BNE FOD
FOC CMP #$99
BNE FOD
LDA #$18
FOD STA P1MEM-1,Y
INY
DEX
BPL GU1
JSR WAIT
DEC PYP
DEC VERT
LDA VERT
BPL GU2
DEC SMY
JMP FULOUT
;
;locate :result in curchr
;
LOOKR LDY SMY
JSR WHERE
LDY SMX
INY
INY
LKRET LDA (JL),Y
STA CURCHR
JSR CKCHAR
RTS
;
LOOKL LDY SMY
JSR WHERE
LDY SMX
DEY
DEY
JMP LKRET
;
LOOKD LDY SMY
INY
JSR WHERE
LDY SMX
JMP LKRET
;
LOOKU LDY SMY
DEY
JSR WHERE
LDY SMX
JMP LKRET
;
;erase chr beneath dozer
;repalce with next char.
;which is a road w/o snow
;
REMOVE LDY SMY
JSR WHERE
LDY SMX
LDA (JL),Y
LDX #15
RB1 CMP ROADS,X
BEQ SF5
DEX
BPL RB1
JMP SF6
SF5 CMP #$1B ;cng car to road
BEQ SF8
CMP #$1D
BNE SF7
SF8 PHA ;save car
LDA #$61
STA (JL),Y
INY
STA (JL),Y
JSR BONSCR
JSR HORN
PLA
CMP #$1B
BEQ SFA
BNE SF6
SF7 TAX
INX
TXA
STA (JL),Y
INY
LDA (JL),Y
TAX
INX
TXA
STA (JL),Y
CMP #$0B ; fuel?
BEQ SF6
SFA INC ROADG
BNE SH1
INC ROADG+1
;
SH1 JSR DOSCOR ;show score
;
SF6 LDA CURCHR
CMP #$08 ;fuel?
BNE CAR?
;
INC CURCHR ;empty fuel
LDY SMY
JSR WHERE
LDX FOFS ;get pos.
FFA LDA JL+1
CMP FULY,X
BEQ FFB
FFC DEX
BPL FFA
RTS ;shouldnt happen
FFB LDA SMX ;put it on
CLC ;screen
ADC JL
CMP FULX,X
BNE FFC
LDA #100 ;got it
STA FTIME,X ;set timer
JSR FILSND ;sound
JSR RESFUL ;show it
JSR DSPFUL
SF2 RTS
;
;hit a car
;
CAR? LDY SMY ;find out
JSR WHERE ;which one
LDX CARCNT
BEQ SF2
CB1 LDA JL+1
CMP CARY,X
BEQ CB2
CB3 DEX
BPL CB1
RTS ;nope
CB2 LDA JL