; TRON 1

	ORG	60000
INIC	LD	A,1
	LD	(X),A
	LD	A,88
	LD	(Y),A
	LD	A,1
	LD	(DX),A
	LD	A,0
	LD	(DY),A
	CALL	#0D6B ;CLS
	EXX
	PUSH	HL
	EXX
	LD	C,255
	LD	B,0
	LD	E,1
	LD	D,1
	CALL	#24BA ;DRAW(255,0)
	LD	C,0
	LD	B,175
	LD	E,1
	LD	D,1
	CALL	#24BA ;DRAW(0,175)
	LD	C,255
	LD	B,0
	LD	E,255
	LD	D,1
	CALL	#24BA ;DRAW(-255,0)
	LD	C,0
	LD	B,175
	LD	E,1
	LD	D,255
	CALL	#24BA ;DRAW(0,-175)
TECLAD	CALL	#028E;KEY_SCAN
	LD	A,E
	CP	#1C ;TECLA"2"
	JR	Z,UP
	CP	#1E ;TECLA"S"
	JR	Z,DOWN
	CP	#25 ;TECLA"Q"
	JR	Z,LEFT
	CP	#15 ;TECLA"E"
	JR	Z,RIGHT
	JR	COORD
DOWN	LD	A,255
	LD	(DY),A;DY=-1
	XOR	A
	LD	(DX),A;DX=0
	JR	COORD
UP	LD	A,1
	LD	(DY),A;DY=1
	XOR	A
	LD	(DX),A;DX=0
	JR	COORD
LEFT	LD	A,255
	LD	(DX),A;DX=-1
	XOR	A
	LD	(DY),A;DY=0
	JR	COORD
RIGHT	LD	A,1
	LD	(DX),A;DX=1
	XOR	A
	LD	(DY),A;DY=0
COORD	LD	A,(X)
	LD	HL,DX
	ADD	A,(HL)
	LD	(X),A;X=X+DX
	LD	A,(Y)
	LD	HL,DY
	ADD	A,(HL)
	LD	(Y),A;Y=Y+DY
CHECK	LD	A,(X)
	CALL	#2D28;X-STACK
	LD	A,(Y)
	CALL	#2D28;Y-STACK
	CALL	#22CB;POINT
	CALL	#2314;A=POINT
	AND	A
	RET	NZ;FIN
DIB	LD	A,(X)
	CALL	#2D28
	LD	A,(Y)
	CALL	#2D28;X,Y-STACK
	CALL	#22DC; PLOT
	JR	TECLAD

X	DEFB	5
Y	DEFB	88
DX	DEFB	1
DY	DEFB	0

	END
