;
; void clrscr (void);
;
        .export         _clrscr
        .include        "c1p.inc"

; Adapted from the Challenger Character Graphics
; Reference Manual, "2.3.3 MACHINE LANGUAGE SCREEN CLEAR"
; This is self-modifying code!
BANKS = VIDEORAMSIZE / $100

_clrscr:
        lda #$20 ;' '
		ldy #BANKS
		ldx #$00
staloc:
		sta SCRNBASE,X
		inx
		bne staloc
		inc staloc+2
		dey
		bne staloc
		lda #>(SCRNBASE) ; load high byte
		sta staloc+2     ; restore base address
		rts