zerobss.s

;
; Ullrich von Bassewitz, 17.09.1998
;
; Zero the bss segment.
;

	.export		zerobss
	.import		__BSS_RUN__, __BSS_SIZE__
	.importzp	ptr1


.code

zerobss:
	lda	#<__BSS_RUN__
	sta	ptr1
	lda	#>__BSS_RUN__
	sta	ptr1+1
	lda	#0
	tay

; Clear full pages

L1:	ldx	#>__BSS_SIZE__
	beq	L3
L2:	sta	(ptr1),y
   	iny
   	bne	L2
	inc	ptr1+1
	dex
	bne	L2

; Clear remaining page (y is zero on entry)

L3:	cpy	#<__BSS_SIZE__
	beq	L4
	sta	(ptr1),y
	iny
	bne	L3

; Done

L4:	rts

zerobss.s.html; generated on Sat Oct 13 22:41:32 2001 by ca65html
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