cc65/libsrc/common/copydata.s

;
; Ullrich von Bassewitz, 1998-12-07, 2004-12-01
;
; Copy the data segment from the LOAD to the RUN location
;

	.export		copydata
	.import		__DATA_LOAD__, __DATA_RUN__, __DATA_SIZE__
	.importzp	ptr1, ptr2, tmp1


copydata:
	lda    	#<__DATA_LOAD__	        ; Source pointer
	sta	ptr1
	lda	#>__DATA_LOAD__
	sta	ptr1+1

	lda	#<__DATA_RUN__	        ; Target pointer
	sta	ptr2
	lda	#>__DATA_RUN__
	sta	ptr2+1

        ldx     #<~__DATA_SIZE__
        lda     #>~__DATA_SIZE__        ; Use -(__DATASIZE__+1)
        sta     tmp1
        ldy     #$00

; Copy loop

@L1:    inx
        beq     @L3

@L2:    lda	(ptr1),y
        sta	(ptr2),y
        iny
        bne     @L1
        inc	ptr1+1
        inc	ptr2+1	       	        ; Bump pointers
        bne	@L1		        ; Branch always (hopefully)

; Bump the high counter byte

@L3:    inc     tmp1
        bne     @L2

; Done

        rts