;
; Ullrich von Bassewitz, 26.11.1998
;
; void clrscr (void);
;

	.export	    	_clrscr
	.import		plot
       	.importzp   	ptr1

	.include    	"pet.inc"

_clrscr:

; Set the screen base address

	lda	#$00
	sta	ptr1
	lda	#$80
	sta	ptr1+1

; Determine, how many pages to fill

	ldx 	#4
	lda	SCR_LINELEN     ; Check length of one line
	cmp	#40+1
       	bcc    	L1
	ldx	#8

; Clear the screen

L1:    	lda    	#$20		; Screen code for blank
	ldy	#$00
L2:	sta	(ptr1),y
   	iny
   	bne	L2
   	inc	ptr1+1
	dex
	bne	L2

; Set the cursor to 0/0

	lda	#0
	sta	CURS_X
	sta	CURS_Y
	jmp	plot

	rts

