;BOTHKILL by Marian Cascaval
;                     '

;Status of Players Fires.
STP1F1  EQU     #5B70
STP1F2  EQU     #5B71
STP1F3  EQU     #5B72
STP1F4  EQU     #5B7F
STP1F5  EQU     #5B80
STP2F1  EQU     #5B89
STP2F2  EQU     #5B8A
STP2F3  EQU     #5B8B
STP2F4  EQU     #5B8C
STP2F5  EQU     #5B8D
INTCTR  EQU     #D6D7


        ORG     #D6D8
;Set interrupt table
        DI
        IM2
        LD      HL,#D500        ;Table begins at 54528.
        LD      A,#E1
        LD      B,0
FILTBL  LD      (HL),A
        INC     HL
        DJNZ    FILTBL
        LD      (HL),A
        LD      A,#D5
        LD      I,A
;Prepare Game
        XOR     A
        LD      (INTCTR),A
        LD      A,#1F           ;Set border to purple:
	LD	(#5C48),A	;BORDCR = #1F.
        LD      HL,#4000        ;Clear screen.
        LD      DE,#1800        ;
CLSCR1  XOR     A       	;
        LD      (HL),A          ;
        INC     HL              ;
        DEC     DE              ;
        LD      A,D             ;
        OR      E               ;
        JR      NZ,CLSCR1       ;
	LD	HL,#5800	;Clear attributes and
	LD	DE,#0300	;set them to black.
CLRATR  LD      A,#46           ;
        LD      (HL),A          ;
        INC     HL              ;
        DEC     DE              ;
        LD      A,D             ;
        OR      E               ;
        JR      NZ,CLRATR       ;
        CALL    PUPTXT          ;Print upper text.
        CALL    PLOTXT          ;Print lower text.
        LD      A,#00   	;Set Game status to Begin:
        LD      (#5BA2),A       ;#5BA2 = 0.
        LD      A,#03   	;Set no. of lives = 3
        LD      (#5BA4),A       ;for P1 and
        LD      (#5BA5),A       ;for P2.
;'CONTINUE' Game
CTGAME  LD      SP,#9C40        ;Set the Stack Pointer.
        LD      A,#01           ;Color border blue.
        OUT     (#FE),A         ;
	LD	HL,#5820	;Clear playing area
	LD	DE,#02C0	;except the 4
CLSCR2  LD      A,#46           ;screen corner attributes.
        LD      (HL),A          ;
        INC     HL              ;
        DEC     DE              ;
        LD      A,D             ;
        OR      E               ;
        JR      NZ,CLSCR2       ;
        LD      A,#46   	;Clear the following attributes:
	LD	(#581F),A	;upper right corner attribute,
	LD	(#5AE0),A	;lower left corner attribute.
        LD      A,#50   	;Set bright red the attributes:
        LD      (#5800),A       ;P1's upper square,
        LD      (#5840),A       ;P1's lower square and
        LD      (#5ADF),A       ;P2's middle square.
        LD      A,#70   	;Set bright yellow the attributes:
        LD      (#5820),A       ;P1's middle square,
        LD      (#5ABF),A       ;P2's upper square and
        LD      (#5AFF),A       ;P2's lower square.
        LD      A,#00   	;Disable FIREs; 5 Fires/Player.
        LD      (STP1F1),A      ;P1F1 off.
        LD      (STP1F2),A      ;P1F2 off.
        LD      (STP1F3),A      ;P1F3 off.
        LD      (STP1F4),A      ;P1F4 off.
        LD      (STP1F5),A      ;P1F5 off.
        LD      (STP2F1),A      ;P2F1 off.
        LD      (STP2F2),A      ;P2F2 off.
        LD      (STP2F3),A      ;P2F3 off.
        LD      (STP2F4),A      ;P2F4 off.
        LD      (STP2F5),A      ;P2F5 off.
;Start Game (BEGIN/CONTINUE)
        CALL    BCGAME          ;Begin/Continue Game.
        LD      BC,#5820        ;BC holds P1 coordinates.
        LD      DE,#5ADF        ;DE holds P2 coordinates.
        EXX                     ;Saves BC & DE values.
        EI
;Scan Fire keys
SCFRKY  LD      BC,#FEFE        ;Scan 'Caps Shift' key
        IN      A,(C)           ;which is P1 Fire key.
        RRA                     ;
        CALL    NC,P1FPRS       ;P1 Fire key pressed.
	LD	BC,#7FFE	;Scan 'Space' key.
        IN      A,(C)           ;which is P2 Fire key.
        RRA                     ;
        CALL    NC,P2FPRS       ;P2 Fire key pressed.
        LD      A,#01           ;Color border.
        OUT     (#FE),A         ;
        LD      DE,#2710        ;'Delay' routine.
DELAY1  DEC     DE              ;
        LD      A,D             ;
        OR      E               ;
        JR      NZ,DELAY1       ;
        JR      SCFRKY          ;Jump to scan Fire keys.
;Move Player1 up
MVP1UP  EXX                     ;Save BC & DE.
        LD      A,B     	;Check if middle sqaure
        XOR     #58     	;has reached max position
        JR      NZ,P1UP         ;i.e. #5820.
        LD      A,C     	;If max position reached then
        XOR     #20             ;don't move P1 and exit.
        JR      Z,NOP1UP
P1UP    LD      H,B             ;Move P1 up.
        LD      L,C             ;
        LD      BC,#0020        ;
        ADD     HL,BC           ;
        LD      A,#00           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,BC           ;
        LD      A,#50           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,BC           ;
        OR      A               ;
        SBC     HL,BC           ;
        LD      (HL),A          ;
        ADD     HL,BC           ;
        LD      A,#70           ;
        LD      (HL),A          ;
        LD      B,H             ;
        LD      C,L             ;
NOP1UP	EXX                     ;Restore BC & DE before
        RET                     ;RETurn.
;Move Player2 up
MVP2UP  EXX                     ;Move P2 up; Save BC & DE.
        LD      A,D     	;Check if middle sqaure
        XOR     #58     	;has reached max position
        JR      NZ,P2UP         ;i.e. #583F.
        LD      A,E     	;If max position reached then
        XOR     #3F             ;don't move P2 and exit.
        JR      Z,NOP2UP 
P2UP    LD      H,D             ;Move P2 up.
        LD      L,E             ;
        LD      DE,#0020        ;
        ADD     HL,DE           ;
        LD      A,#00           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,DE           ;
        LD      A,#70           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,DE           ;
        OR      A               ;
        SBC     HL,DE           ;
        LD      (HL),A          ;
        ADD     HL,DE           ;
        LD      A,#50           ;
        LD      (HL),A          ;
        LD      D,H             ;
        LD      E,L             ;
NOP2UP	EXX                     ;Restore BC & DE before
        RET                     ;RETurn.
;Move Player1 down
MVP1DN  EXX                     ;Move P1 down; Save BC & DE.
        LD      A,B     	;Check if middle sqaure
        XOR     #5A     	;has reached max position
        JR      NZ,P1DN         ;i.e. #5AC0.
        LD      A,C     	;If max position reached then
        XOR     #C0             ;don't move P1 and exit.
        JR      Z,NOP1DN 
P1DN    LD      H,B             ;Move P1 down.
        LD      L,C             ;
        LD      BC,#0020        ;
        OR      A               ;
        SBC     HL,BC           ;
        LD      A,#00           ;
        LD      (HL),A          ;
        ADD     HL,BC           ;
        LD      A,#50           ;
        LD      (HL),A          ;
        ADD     HL,BC           ;
        ADD     HL,BC           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,BC           ;
        LD      A,#70           ;
        LD      (HL),A          ;
        LD      B,H             ;
        LD      C,L             ;
NOP1DN	EXX                     ;Restore BC & DE before
        RET                     ;RETurn.
;Move Player2 down
MVP2DN  EXX                     ;Move P2 down; Save BC & DE.
        LD      A,D     	;Check if middle sqaure
        XOR     #5A     	;has reached max position
        JR      NZ,P2DN         ;i.e. #5ADF.
        LD      A,E     	;If max position reached then
        XOR     #DF             ;don't move P2 and exit.
        JR      Z,NOP2DN 
P2DN    LD      H,D             ;Move P2 down.
        LD      L,E             ;
        LD      DE,#0020        ;
        OR      A               ;
        SBC     HL,DE           ;
        LD      A,#00           ;
        LD      (HL),A          ;
        ADD     HL,DE           ;
        LD      A,#70           ;
        LD      (HL),A          ;
        ADD     HL,DE           ;
        ADD     HL,DE           ;
        LD      (HL),A          ;
        OR      A               ;
        SBC     HL,DE           ;
        LD      A,#50           ;
        LD      (HL),A          ;
        LD      D,H             ;
        LD      E,L             ;
NOP2DN	EXX                     ;Restore BC & DE before
        RET                     ;RETurn.
;Player1 Fire key pressed
P1FPRS  LD      A,(STP1F1)      ;Test P1F1 status,
        CP      #00             ;if P1F1 slot free then
        JR      Z,LNP1F1        ;P1F1 launch.
        LD      A,(STP1F2)      ;Test P1F2 status,
        CP      #00             ;if P1F2 slot free then
        JR      Z,LNP1F2        ;P1F2 launch.
        LD      A,(STP1F3)      ;Test P1F3 status,
        CP      #00             ;if P1F3 slot free then
        JP      Z,LNP1F3        ;P1F3 launch.
        LD      A,(STP1F4)      ;Test P1F4 status,
        CP      #00             ;if P1F4 slot free then
        JP      Z,LNP1F4        ;P1F4 launch.
        LD      A,(STP1F5)      ;Test P1F5 status,
        CP      #00             ;if P1F5 slot free then
        JP      Z,LNP1F5        ;P1F5 launch.
        RET                     ;RET from Test P1F.
LNP1F1  CALL    HITSND          ;Fire sound P1F1.
	EXX		
        LD      H,B             ;Move P1F1 one position
        LD      L,C             ;after the P1 position,
        INC     HL              ;i.e. BC+1.
        LD      A,#70           ;
        LD      (HL),A          ;
LD89B   CALL    LDA12
        LD      A,(STP1F1)
	CP	#01	
        JR      Z,LD8B4
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	PUSH	BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	(#5B79),HL	
	POP	BC	
	POP	HL	
LD8B4   PUSH    BC
	LD	BC,(#5B79)	
	LD	A,H	
	XOR	B	
        JR      NZ,LD8CB
	LD	A,L	
	XOR	C	
        JR      NZ,LD8CB
	POP	BC	
	LD	A,#00	
        LD      (STP1F1),A
	DEC	HL	
	LD	(HL),A	
	EXX		
	RET		
LD8CB   POP     BC
	LD	A,#00	
	DEC	HL	
	LD	(HL),A	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
	LD	(#5B73),HL	
	LD	A,#01	
        LD      (STP1F1),A
	EXX		
	RET		
LNP1F2  CALL    HITSND          ;Fire sound P1F2.
	EXX		
	LD	H,B	
	LD	L,C	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
LD8E8   CALL    LDA12
        LD      A,(STP1F2)
	CP	#01	
        JR      Z,LD901
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	PUSH	BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	(#5B7B),HL	
	POP	BC	
	POP	HL	
LD901   PUSH    BC
	LD	BC,(#5B7B)	
	LD	A,H	
	XOR	B	
        JR      NZ,LD918
	LD	A,L	
	XOR	C	
        JR      NZ,LD918
	POP	BC	
	LD	A,#00	
        LD      (STP1F2),A
	DEC	HL	
	LD	(HL),A	
	EXX		
	RET		
LD918	POP	BC	
	LD	A,#00	
	DEC	HL	
	LD	(HL),A	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
	LD	(#5B75),HL	
	LD	A,#01	
        LD      (STP1F2),A
	EXX		
	RET		
LNP1F3  CALL    HITSND          ;Fire sound P1F3.
	EXX		
	LD	H,B	
	LD	L,C	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
LD935   CALL    LDA12
        LD      A,(STP1F3)
	CP	#01	
        JR      Z,LD94E
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	PUSH	BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	(#5B7D),HL	
	POP	BC	
	POP	HL	
LD94E	PUSH	BC	
	LD	BC,(#5B7D)	
	LD	A,H	
	XOR	B	
        JR      NZ,LD965
	LD	A,L	
	XOR	C	
        JR      NZ,LD965
	POP	BC	
	LD	A,#00	
        LD      (STP1F3),A
	DEC	HL	
	LD	(HL),A	
	EXX		
	RET		
LD965	POP	BC	
	LD	A,#00	
	DEC	HL	
	LD	(HL),A	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
	LD	(#5B77),HL	
	LD	A,#01	
        LD      (STP1F3),A
	EXX		
	RET		
LNP1F4  CALL    HITSND          ;Fire sound P1F4.
	EXX		
	LD	H,B	
	LD	L,C	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
LD982   CALL    LDA12
        LD      A,(STP1F4)
	CP	#01	
        JR      Z,LD99B
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	PUSH	BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	(#5B85),HL	
	POP	BC	
	POP	HL	
LD99B	PUSH	BC	
	LD	BC,(#5B85)	
	LD	A,H	
	XOR	B	
        JR      NZ,LD9B2
	LD	A,L	
	XOR	C	
        JR      NZ,LD9B2
	POP	BC	
	LD	A,#00	
        LD      (STP1F4),A
	DEC	HL	
	LD	(HL),A	
	EXX		
	RET		
LD9B2	POP	BC	
	LD	A,#00	
	DEC	HL	
	LD	(HL),A	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
	LD	(#5B81),HL	
	LD	A,#01	
        LD      (STP1F4),A
	EXX		
	RET		
LNP1F5  CALL    HITSND          ;Fire sound P1F5.
	EXX		
	LD	H,B	
	LD	L,C	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
LD9CF   CALL    LDA12
        LD      A,(STP1F5)
	CP	#01	
        JR      Z,LD9E8
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	PUSH	BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	(#5B87),HL	
	POP	BC	
	POP	HL	
LD9E8	PUSH	BC	
	LD	BC,(#5B87)	
	LD	A,H	
	XOR	B	
        JR      NZ,LD9FF
	LD	A,L	
	XOR	C	
        JR      NZ,LD9FF
	POP	BC	
	LD	A,#00	
        LD      (STP1F5),A
	DEC	HL	
	LD	(HL),A	
	EXX		
	RET		
LD9FF	POP	BC	
	LD	A,#00	
	DEC	HL	
	LD	(HL),A	
	INC	HL	
	LD	A,#70	
	LD	(HL),A	
	LD	(#5B83),HL	
	LD	A,#01	
        LD      (STP1F5),A
	EXX		
	RET		
LDA12	LD	A,#01	
	LD	(#5B06),A	
	PUSH	DE	
LDA18	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
	ADD	HL,DE	
	LD	D,H	
	LD	E,L	
	POP	HL	
        CALL    LDA64
        JP      C,LDA86
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	OR	A	
	SBC	HL,DE	
	LD	D,H	
	LD	E,L	
	POP	HL	
        CALL    LDA64
        JP      C,LDA86
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
	ADD	HL,DE	
	LD	D,H	
	LD	E,L	
	POP	HL	
        CALL    LDA64
        JP      C,LDA86
	LD	A,(#5B06)	
	CP	#01	
        JR      Z,LDA5C
	POP	DE	
	RET		
LDA5C	INC	HL	
	LD	A,#00	
	LD	(#5B06),A	
        JR      LDA18
LDA64   LD      A,H
	XOR	D	
	OR	A	
	RET	NZ	
	LD	A,L	
	XOR	E	
	OR	A	
        RET     NZ
        SCF
        RET
HITSND  LD      HL,#0300        ;Fire sound routine.
LDA74   LD      DE,#0001        ;
        PUSH    HL              ;
        CALL    SNDRTN          ;
        POP     HL              ;
        LD      DE,#0010        ;
        AND     A               ;
        SBC     HL,DE           ;
        JR      NZ,LDA74        ;
        RET                     ;
LDA86	POP     DE              ;Flashing Player 2.
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
	ADD	HL,DE	
	LD	D,H	
	LD	E,L	
	LD	A,(DE)	
        OR      #80             ;Set Flash attribute.
	LD	(DE),A	
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
        OR      A               ;Set Carry Flag=0.
	SBC	HL,DE	
        OR      A               ;Set Carry Flag=0.
	SBC	HL,DE	
	LD	D,H	
	LD	E,L	
	LD	A,(DE)	
        OR      #80             ;Set Flash attribute.
	LD	(DE),A	
	LD	HL,#0000	
	ADD	HL,DE	
	LD	DE,#0020	
	ADD	HL,DE	
	LD	D,H	
	LD	E,L	
	LD	A,(DE)	
        OR      #80             ;Set Flash attribute.
	LD	(DE),A	
        CALL    LDF08
        CALL    LDB1B           ;Call hit sound ???
LDABC	LD	DE,#FFFF	
LDABF	DEC	DE	
	LD	A,D	
	OR	E	
        JR      NZ,LDABF
        CALL    LE0EA
        JP      CTGAME
;Move Player1 FIREs.
MVP1F   LD      A,(STP1F1)       ;Test PLAYER1's
        CP      #01     	;all 5 FIREs status.
        CALL    Z,LDAF3 	;If = 0 then skip to check
        LD      A,(STP1F2)       ;next FIRE or RET if
        CP      #01     	;FIRE 5 reached.
        CALL    Z,LDAFB 	;If = 1 then move FIRE
        LD      A,(STP1F3)       ;one position and check
        CP      #01             ;next FIRE or RET if
        CALL    Z,LDB03         ;FIRE 5 reached.
        LD      A,(STP1F4)       ;Check P1F4 status.
        CP      #01             ;
        CALL    Z,LDB0B         ;
        LD      A,(STP1F5)       ;Check P1F5 status.
        CP      #01             ;
        CALL    Z,LDB13         ;
        RET                     ;Finish testing P1F status.
LDAF3	EXX		
        LD      HL,(#5B73)      ;Load position of P1F1.
        CALL    LD89B
	RET		
LDAFB	EXX		
        LD      HL,(#5B75)      ;Load position of P1F2.
        CALL    LD8E8
	RET		
LDB03	EXX		
        LD      HL,(#5B77)      ;Load position of P1F3.
        CALL    LD935
	RET		
LDB0B	EXX		
        LD      HL,(#5B81)      ;Load position of P1F4.
        CALL    LD982
	RET		
LDB13	EXX		
        LD      HL,(#5B83)      ;Load position of P1F5.
        CALL    LD9CF
	RET		
LDB1B   LD      BC,#FA04        ;Play hit sound.
	LD	HL,#0200	
        LD      DE,#000F
;Hit sound routine.
LDB24   PUSH    HL
	PUSH	DE	
	PUSH	BC	
        CALL    SNDRTN          ;Call #03B6 instead of #03B5 in
        POP     BC              ;order to skip the 'DI' instruction
        POP     DE              ;at the start of ROM sound routine;
        POP     HL              ;In this way interrupts can be
        LD      A,L             ;serviced while playing sound.
	SUB	C	
	LD	L,A	
        DJNZ    LDB24
        RET
;Player 2 Fire key pressed
P2FPRS  LD      A,(STP2F1)       ;Test P2F1 status,
        CP      #00             ;if P2F1 slot free then
        JR      Z,LDB5A         ;P2F1 launch.
        LD      A,(STP2F2)       ;Test P2F2 status,
        CP      #00             ;if P2F2 slot free then
        JR      Z,LDBA9         ;P2F2 launch.
        LD      A,(STP2F3)       ;Test P2F3 status,
        CP      #00             ;if P2F3 slot free then
        JP      Z,LDBF8         ;P2F3 launch.
        LD      A,(STP2F4)       ;Test P2F4 status,
        CP      #00             ;if P2F4 slot free then
        JP      Z,LDC47         ;P2F4 launch.
        LD      A,(STP2F5)       ;Test P2F5 status,
        CP      #00             ;if P2F5 slot free then
        JP      Z,LDC96         ;P2F5 launch.
        RET                     ;RET from Test P2F.
LDB5A   CALL    HITSND          ;Fire sound P2F1.
	EXX		
	LD	H,D	
	LD	L,E	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
LDB64   CALL    LDCE5
        LD      A,(STP2F1)
	CP	#01	
        JR      Z,LDB7F
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	PUSH	DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	LD	(#5B98),HL	
	POP	DE	
	POP	HL	
LDB7F	PUSH	DE	
	LD	DE,(#5B98)	
	LD	A,H	
	XOR	D	
        JR      NZ,LDB96
	LD	A,L	
	XOR	E	
        JR      NZ,LDB96
	POP	DE	
	LD	A,#00	
        LD      (STP2F1),A
	INC	HL	
	LD	(HL),A	
	EXX		
	RET		
LDB96	POP	DE	
	LD	A,#00	
	INC	HL	
	LD	(HL),A	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
	LD	(#5B8E),HL	
	LD	A,#01	
        LD      (STP2F1),A
	EXX		
	RET		
LDBA9   CALL    HITSND          ;Fire sound P2F2.
	EXX		
	LD	H,D	
	LD	L,E	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
LDBB3   CALL    LDCE5
        LD      A,(STP2F2)
	CP	#01	
        JR      Z,LDBCE
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	PUSH	DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	LD	(#5B9A),HL	
	POP	DE	
	POP	HL	
LDBCE	PUSH	DE	
	LD	DE,(#5B9A)	
	LD	A,H	
	XOR	D	
        JR      NZ,LDBE5
	LD	A,L	
	XOR	E	
        JR      NZ,LDBE5
	POP	DE	
	LD	A,#00	
        LD      (STP2F2),A
	INC	HL	
	LD	(HL),A	
	EXX		
	RET		
LDBE5	POP	DE	
	LD	A,#00	
	INC	HL	
	LD	(HL),A	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
	LD	(#5B90),HL	
	LD	A,#01	
        LD      (STP2F2),A
	EXX		
	RET		
LDBF8   CALL    HITSND          ;Fire sound P2F3.
	EXX		
	LD	H,D	
	LD	L,E	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
LDC02   CALL    LDCE5
        LD      A,(STP2F3)
	CP	#01	
        JR      Z,LDC1D
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	PUSH	DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	LD	(#5B9C),HL	
	POP	DE	
	POP	HL	
LDC1D	PUSH	DE	
	LD	DE,(#5B9C)	
	LD	A,H	
	XOR	D	
        JR      NZ,LDC34
	LD	A,L	
	XOR	E	
        JR      NZ,LDC34
	POP	DE	
	LD	A,#00	
        LD      (STP2F3),A
	INC	HL	
	LD	(HL),A	
	EXX		
	RET		
LDC34	POP	DE	
	LD	A,#00	
	INC	HL	
	LD	(HL),A	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
	LD	(#5B92),HL	
	LD	A,#01	
        LD      (STP2F3),A
	EXX		
	RET		
LDC47   CALL    HITSND          ;Fire sound P2F4.
	EXX		
	LD	H,D	
	LD	L,E	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
LDC51   CALL    LDCE5
        LD      A,(STP2F4)
	CP	#01	
        JR      Z,LDC6C
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	PUSH	DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	LD	(#5B9E),HL	
	POP	DE	
	POP	HL	
LDC6C	PUSH	DE	
	LD	DE,(#5B9E)	
	LD	A,H	
	XOR	D	
        JR      NZ,LDC83
	LD	A,L	
	XOR	E	
        JR      NZ,LDC83
	POP	DE	
	LD	A,#00	
        LD      (STP2F4),A
	INC	HL	
	LD	(HL),A	
	EXX		
	RET		
LDC83	POP	DE	
	LD	A,#00	
	INC	HL	
	LD	(HL),A	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
	LD	(#5B94),HL	
	LD	A,#01	
        LD      (STP2F4),A
	EXX		
	RET		
LDC96   CALL    HITSND          ;Fire sound P2F5.
	EXX		
	LD	H,D	
	LD	L,E	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
LDCA0   CALL    LDCE5
        LD      A,(STP2F5)
	CP	#01	
        JR      Z,LDCBB
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,DE	
	PUSH	DE	
	LD	DE,#0020	
	OR	A	
	SBC	HL,DE	
	LD	(#5BA0),HL	
	POP	DE	
	POP	HL	
LDCBB	PUSH	DE	
	LD	DE,(#5BA0)	
	LD	A,H	
	XOR	D	
        JR      NZ,LDCD2
	LD	A,L	
	XOR	E	
        JR      NZ,LDCD2
	POP	DE	
	LD	A,#00	
        LD      (STP2F5),A
	INC	HL	
	LD	(HL),A	
	EXX		
	RET		
LDCD2	POP	DE	
	LD	A,#00	
	INC	HL	
	LD	(HL),A	
	DEC	HL	
	LD	A,#50	
	LD	(HL),A	
	LD	(#5B96),HL	
	LD	A,#01	
        LD      (STP2F5),A
	EXX		
	RET		
LDCE5	LD	A,#01	
	LD	(#5B07),A	
	PUSH	BC	
LDCEB	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	B,H	
	LD	C,L	
	POP	HL	
        CALL    LDD37
        JP      C,LDD41
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	OR	A	
	SBC	HL,BC	
	OR	A	
	SBC	HL,BC	
	LD	B,H	
	LD	C,L	
	POP	HL	
        CALL    LDD37
        JP      C,LDD41
	PUSH	HL	
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	B,H	
	LD	C,L	
	POP	HL	
        CALL    LDD37
        JP      C,LDD41
	LD	A,(#5B07)	
	CP	#01	
        JR      Z,LDD2F
	POP	BC	
	RET		
LDD2F	DEC	HL	
	LD	A,#00	
	LD	(#5B07),A	
        JR      LDCEB
LDD37   LD      A,H
	XOR	B	
	OR	A	
	RET	NZ	
	LD	A,L	
	XOR	C	
	OR	A	
        RET     NZ
        SCF
        RET
LDD41   POP     BC              ;Flashing Player 1.
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	B,H	
	LD	C,L	
	LD	A,(BC)	
	OR	#80	
	LD	(BC),A	
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	OR	A	
	SBC	HL,BC	
	OR	A	
	SBC	HL,BC	
	LD	B,H	
	LD	C,L	
	LD	A,(BC)	
	OR	#80	
	LD	(BC),A	
	LD	HL,#0000	
	ADD	HL,BC	
	LD	BC,#0020	
	ADD	HL,BC	
	LD	B,H	
	LD	C,L	
	LD	A,(BC)	
	OR	#80	
	LD	(BC),A	
	EXX		
        CALL    LDFA0
        CALL    LDB1B
        JP      LDABC
;Move Player2 FIREs.
MVP2F   LD      A,(STP2F1)       ;Test PLAYER2's
        CP      #01     	;all 5 FIREs status.
        CALL    Z,LDDA4 	;If = 0 then skip to check
        LD      A,(STP2F2)       ;next FIRE or RET if
        CP      #01     	;FIRE 5 reached.
        CALL    Z,LDDAC 	;If = 1 then move FIRE
        LD      A,(STP2F3)       ;one position and check
        CP      #01             ;next FIRE or RET if
        CALL    Z,LDDB4         ;FIRE 5 reached.
        LD      A,(STP2F4)       ;Check P2F4 status.
        CP      #01             ;
        CALL    Z,LDDBC         ;
        LD      A,(STP2F5)       ;Check P2F5 status.
        CP      #01             ;
        CALL    Z,LDDC4         ;
        RET                     ;Finish testing P2F status.
LDDA4	EXX		
        LD      HL,(#5B8E)      ;Load position of P2F1.
        CALL    LDB64           ;Move P2F1.
	RET		
LDDAC	EXX		
        LD      HL,(#5B90)      ;Load position of P2F2.
        CALL    LDBB3           ;Move P2F2.
	RET		
LDDB4	EXX		
        LD      HL,(#5B92)      ;Load position of P2F3.
        CALL    LDC02           ;Move P2F3.
	RET		
LDDBC	EXX		
        LD      HL,(#5B94)      ;Load position of P2F4.
        CALL    LDC51           ;Move P2F4.
	RET		
LDDC4	EXX		
        LD      HL,(#5B96)      ;Load position of P2F5.
        CALL    LDCA0           ;Move P2F5.
	RET		
PUPTXT  LD      HL,LDDEC        ;Print upper text.
        LD      B,#02   	;Page 176, section 5.5.2.
LDDD1   PUSH    BC      	;Print 2 times:
        LD      B,(HL)  	;1 time bright green and
        INC     HL      	;1 time bright blue.
        CALL    LDDDB           ;
        POP     BC              ;
        DJNZ    LDDD1           ;
        RET             	;RET from Print upper text.
LDDDB	PUSH	HL	
	PUSH	BC	
        LD      A,#02   	;Select channel 2.
        CALL    #1601   	;Select screen.
	POP	BC	
	POP	HL	
LDDE4   LD      A,(HL)  	;Load character to be printed.
        SUB     #64     	;Decode character.
        RST     #10     	;Character print routine.
	INC	HL	
        DJNZ    LDDE4
        RET             	;Print upper text - end.
                                ;DEFB upper text - begin.
LDDEC	DEFB	#14,#7A,#64,#65,#74,#68,#75,#64,#B4,#B6
	DEFB	#B3,#AB,#B6,#A5,#B1,#B1,#A9,#A8,#84,#A6
	DEFB	#BD,#16,#7A,#64,#74,#74,#69,#75,#64,#B1
	DEFB	#A5,#B6,#AD,#A5,#B2,#84,#A7,#A5,#B7,#A7
	DEFB	#A5,#BA,#A5,#B0
                        	;DEFB upper text - end.
PLOTXT  LD      A,#44           ;Prin lower text.
        LD      B,#18           ;
        LD      HL,#5AE3        ;
LDE1F   LD      (HL),A          ;
        INC     HL              ;
        DJNZ    LDE1F           ;
        LD      A,#43           ;
        LD      (#5AEA),A       ;
        LD      (#5AFB),A       ;
        LD      A,#46           ;
        LD      (#5AEB),A       ;
        LD      A,#42           ;
        LD      (#5AFC),A       ;
        LD      HL,#5AED        ;
        LD      A,#4F           ;
        LD      B,#06           ;
LDE3C   LD      (HL),A          ;
        INC     HL              ;
        DJNZ    LDE3C           ;
        LD      HL,LDE6C        ;
        LD      DE,#51E3        ;
        PUSH    HL              ;
        PUSH    DE              ;
LDE48   POP     DE              ;Is really necessary?
        POP     HL              ;Is really necessary?
        PUSH    HL              ;Is really necessary?
        PUSH    DE              ;Is really necessary?
        LD      BC,#001A        ;
        LDIR                    ;
LDE51   POP     DE              ;
        POP     HL              ;
        LD      BC,#001A        ;
        ADD     HL,BC           ;
        EX      DE,HL           ;
        LD      BC,#0100        ;
        ADD     HL,BC           ;
        EX      DE,HL           ;
        PUSH    HL              ;
        PUSH    DE              ;
        LD      A,D             ;
        XOR     #57             ;
        JR      NZ,LDE48        ;
        LD      A,E             ;
        XOR     #E3             ;
        JR      NZ,LDE48        ;
        POP     DE              ;
        POP     HL              ;
LDE6B   RET             	;Prin lower text.
LDE6C                   	;DEFB upper lower - begin.
	DEFB	#7C,#60,#3C,#C2,#7E,#7C,#1C,#18,#3C,#00
	DEFB	#01,#C6,#75,#12,#A2,#00,#00,#7C,#60,#3C
	DEFB	#C2,#7E,#7C,#3C,#18,#3C,#63,#60,#63,#64
	DEFB	#60,#63,#2C,#18,#43,#00,#61,#29,#25,#14
	DEFB	#A2,#06,#00,#63,#60,#63,#64,#60,#63,#43
	DEFB	#18,#43,#63,#60,#63,#38,#7C,#63,#0C,#00
	DEFB	#04,#00,#91,#C9,#27,#18,#A2,#09,#00,#63
	DEFB	#60,#63,#38,#7C,#63,#03,#00,#04,#7C,#60
	DEFB	#7F,#18,#60,#7C,#0C,#00,#03,#00,#91,#29
	DEFB	#27,#18,#A2,#09,#00,#7C,#60,#7F,#18,#60
	DEFB	#7C,#3C,#00,#03,#60,#60,#63,#18,#60,#64
	DEFB	#0C,#18,#43,#00,#61,#29,#25,#14,#A2,#06
	DEFB	#00,#60,#60,#63,#18,#60,#64,#60,#18,#43
	DEFB	#60,#7E,#63,#18,#7E,#62,#3E,#18,#3C,#00
	DEFB	#01,#C6,#25,#12,#BB,#80,#00,#60,#7E,#63
	DEFB	#18,#7E,#62,#7E,#18,#3C
                        	;DEFB lower text - end.
LDF08	LD	A,(#5BA4)	
	DEC	A	
	LD	(#5BA4),A	
        JR      Z,LDF46
	CP	#02	
        JR      Z,LDF2B
        LD      HL,LE0DE
	LD	DE,#51FC	
	LD	B,#06	
LDF1D	LD	A,(HL)	
	LD	(DE),A	
LDF1F	INC	HL	
LDF20	PUSH	HL	
LDF21	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDF1D
	RET		
LDF2B   LD      HL,LE0E4
	LD	DE,#51FC	
LDF31	LD	B,#06	
LDF33	LD	A,(HL)	
	LD	(DE),A	
	INC	HL	
	PUSH	HL	
	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDF33
	LD	A,#01	
	LD	(#5BA2),A	
	RET		
LDF46   LD      HL,LE0D8
	LD	DE,#51FC	
	LD	B,#06	
LDF4E	LD	A,(HL)	
	LD	(DE),A	
	INC	HL	
	PUSH	HL	
	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDF4E
        LD      HL,LDF84
	LD	B,#01	
LDF60	PUSH	BC	
	LD	B,(HL)	
	INC	HL	
        CALL    LDF72
	POP	BC	
	LD	DE,#FFFF	
LDF6A	DEC	DE	
	LD	A,D	
	OR	E	
        JR      NZ,LDF6A
        DJNZ    LDF60
LDF71	RET		
LDF72	PUSH	HL	
	PUSH	BC	
	LD	A,#02	
	CALL	#1601	
	POP	BC	
	POP	HL	
LDF7B	LD	A,(HL)	
	SUB	#64	
	RST	#10	
	INC	HL	
        DJNZ    LDF7B
LDF82   JR      LDF9A
LDF84                           ;DEFB - start.
        DEFB #15,#7A,#6F,#6E,#74,#6B,#75,#64
        DEFB #77,#65,#B4,#B0,#A5,#BD,#A9,#B6
        DEFB #95,#84,#BB,#AD,#B2,#B7
                                ;DEFB - end.
LDF9A	LD	A,#00	
	LD	(#5BA2),A	
	RET		
LDFA0	LD	A,(#5BA5)	
	DEC	A	
	LD	(#5BA5),A	
        JR      Z,LDFDE
	CP	#02	
        JR      Z,LDFC3
        LD      HL,LE0DE
	LD	DE,#51EB	
	LD	B,#06	
LDFB5	LD	A,(HL)	
	LD	(DE),A	
	INC	HL	
	PUSH	HL	
	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDFB5
	RET		
LDFC3   LD      HL,LE0E4
	LD	DE,#51EB	
	LD	B,#06	
LDFCB	LD	A,(HL)	
	LD	(DE),A	
	INC	HL	
	PUSH	HL	
	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDFCB
	LD	A,#01	
	LD	(#5BA2),A	
	RET		
LDFDE   LD      HL,LE0D8
	LD	DE,#51EB	
	LD	B,#06	
LDFE6	LD	A,(HL)	
	LD	(DE),A	
	INC	HL	
	PUSH	HL	
	EX	DE,HL	
	LD	DE,#0100	
	ADD	HL,DE	
	EX	DE,HL	
	POP	HL	
        DJNZ    LDFE6
        LD      HL,LE01C
	LD	B,#01	
LDFF8	PUSH	BC	
	LD	B,(HL)	
	INC	HL	
        CALL    LE00A
LDFFE	POP	BC	
	LD	DE,#FFFF	
LE002	DEC	DE	
	LD	A,D	
	OR	E	
        JR      NZ,LE002
        DJNZ    LDFF8
	RET		
LE00A	PUSH	HL	
	PUSH	BC	
	LD	A,#02	
	CALL	#1601	
	POP	BC	
	POP	HL	
LE013	LD	A,(HL)	
	SUB	#64	
	RST	#10	
	INC	HL	
        DJNZ    LE013
        JR      LE032
LE01C                           ;DEFB - start.
        DEFB #15,#7A,#6F,#6E,#74,#6B,#75,#64
        DEFB #77,#65,#B4,#B0,#A5,#BD,#A9,#B6
        DEFB #96,#84,#BB,#AD,#B2,#B7
                                ;DEFB - end.
LE032	LD	A,#00	
	LD	(#5BA2),A	
        RET
;Test Game status to Begin/Continue Game
BCGAME  LD      A,(#5BA2)       ;Test Game status.
        CP      #00     	;If 0 then Game is to begin.
        JR      Z,LE089 	;Jump to begin Game.
        LD      HL,LE067
	LD	B,#02	
LE044	PUSH	BC	
	LD	B,(HL)	
	INC	HL	
        CALL    LE056   	;Print ‚CONTINUE' message.
	POP	BC	
	LD	DE,#FFFF	;Dealy for the
LE04E   DEC     DE      	;'CONTINUE' message.
        LD      A,D             ;
        OR      E               ;
        JR      NZ,LE04E        ;
        DJNZ    LE044
	RET		
LE056   PUSH    HL      	;Print ‚CONTINUE' message.
        PUSH    BC              ;
        LD      A,#02           ;
        CALL    #1601           ;
        POP     BC              ;
        POP     HL              ;
LE05F   LD      A,(HL)          ;
        SUB     #64             ;
        RST     #10             ;
        INC     HL              ;
        DJNZ    LE05F           ;
        RET             	;Finish printing message.
LE067                           ;DEFB - start.
        DEFB #11,#7A,#6F,#70,#74,#6B,#75,#64
        DEFB #77,#65,#A7,#B3,#B2,#B8,#AD,#B2
        DEFB #B9,#A9,#0F,#7A,#6F,#70,#75,#64
        DEFB #77,#65,#84,#84,#84,#84,#84,#84
        DEFB #84,#84
                                ;DEFB - end.
LE089   LD      A,#03           ;Begin new Game and
        LD      (#5BA4),A       ;set no. of lives = 3
        LD      (#5BA5),A       ;for P1 and P2.
        CALL    PLOTXT
        LD      HL,LE0BC        ;Load address of DEFB.
	LD	B,#02	
LE099	PUSH	BC	
	LD	B,(HL)	
	INC	HL	
        CALL    LE0AB   	;Print ‚BEGIN' message.
	POP	BC	
	LD	DE,#FFFF	;Dealy for the
LE0A3   DEC     DE      	;'BEGIN' message.
        LD      A,D             ;
        OR      E               ;
        JR      NZ,LE0A3        ;
        DJNZ    LE099
	RET		
LE0AB   PUSH    HL      	;Print ‚BEGIN' message.
        PUSH    BC              ;
        LD      A,#02           ;
        CALL    #1601           ;
        POP     BC              ;
        POP     HL              ;
LE0B4   LD      A,(HL)          ;
        SUB     #64             ;
        RST     #10             ;
        INC     HL              ;
        DJNZ    LE0B4           ;
        RET             	;Finish printing message.
LE0BC                           ;DEFB - start.
        DEFB #0E,#7A,#6F,#71,#74,#6B,#75,#64
        DEFB #77,#65,#A6,#A9,#AB,#AD,#B2,#0C
        DEFB #7A,#6F,#71,#75,#64,#77,#65,#84
        DEFB #84,#84,#84,#84
LE0D8   DEFB #3C,#67,#6B,#73,#63,#3C
LE0DE   DEFB #1C,#2C,#0C,#0C,#0C,#3E
LE0E4   DEFB #3C,#43,#03,#3C,#60,#7E
                                ;DEFB - end.
LE0EA   LD   HL,LE10A
        LD   B,#01
LE0EF   PUSH BC
        LD   B,(HL)
        INC  HL
        CALL LE0F9
        POP  BC
        DJNZ LE0EF
        RET
LE0F9   PUSH HL
        PUSH BC
        LD   A,#02
        CALL #1601
        POP  BC
        POP  HL
LE102   LD   A,(HL)
        SUB  A,#64
        RST  #10
        INC  HL
        DJNZ LE102
        RET
LE10A   DEFB #13,#7A,#6F,#6E,#75,#64,#77,#65
        DEFB #84,#84,#84,#84,#84,#84,#84,#84
        DEFB #84,#84,#84,#84
;Same as ROM sound routine at address #03B5
;except the DI and EI instructions
;in order to skip the 'DI' instruction.
;In this way interrupts can be
;serviced while playing sound.
SNDRTN  LD   A,L
        SRL  L
        SRL  L
        CPL
        AND  #03
        LD   C,A
        LD   B,#00
        LD   IX,SRL1
        ADD  IX,BC
        LD   A,(#5C48)
        AND  #38
        RRCA
        RRCA
        RRCA
        OR   #08
SRL1	NOP
        NOP
        NOP
        INC  B
        INC  C
SRL2	DEC  C
        JR   NZ,SRL2
        LD   C,#3F
        DEC  B
        JP   NZ,SRL2
        XOR  #10
        OUT  (#FE),A
        LD   B,H
        LD   C,A
        BIT  4,A
        JR   NZ,SRL3
        LD   A,D
        OR   E
        JR   Z,SRL4
        LD   A,C
        LD   C,L
        DEC  DE
        JP   (IX)
SRL3	LD   C,L
        INC  C
        JP   (IX)
SRL4	RET

;Interrupt routine
        ORG     #E1E1
        
INTRTN  PUSH    AF              ;Save registers.
        PUSH    BC
        PUSH    DE
        PUSH    HL

        LD      A,(INTCTR)
        XOR     1
        LD      (INTCTR),A
        JR      Z,SCNKEY
        
        CALL    MVP1F           ;Move P1 FIREs.
        CALL    MVP2F           ;Move P2 FIREs.

        JR      NOSCAN

SCNKEY  LD      BC,#FBFE        ;Scan P1 Up key
        IN      A,(C)           ;which is 'Q' key.
        RRA                     ;
        CALL    NC,MVP1UP       ;
        LD      BC,#EFFE        ;Scan P2 Up key
        IN      A,(C)           ;which is '0' key.
        RRA                     ;
        CALL    NC,MVP2UP       ;
        LD      BC,#FDFE        ;Scan P1 Down key
        IN      A,(C)           ;which is 'S' key.
        RRA                     ;
        RRA                     ;
        CALL    NC,MVP1DN       ;
        LD      BC,#DFFE        ;Scan P2 Down key
        IN      A,(C)           ;which is 'O' key.
        RRA                     ;
        RRA                     ;
        CALL    NC,MVP2DN       ;

NOSCAN  POP     HL              ;Restore registers.
        POP     DE
        POP     BC
        POP     AF
        
        EI
        RETI
        
        END