cc65/libsrc/apple2/cvline.s

;
; Ullrich von Bassewitz, 08.08.1998
;
; void cvlinexy (unsigned char x, unsigned char y, unsigned char length);
; void cvline (unsigned char length);
;

	.export 	_cvlinexy, _cvline, cvlinedirect
	.import		popa, _gotoxy, putchar, newline
	.importzp	tmp1

_cvlinexy:
       	pha	    		; Save the length
	jsr	popa	        ; Get y
       	jsr    	_gotoxy		; Call this one, will pop params
   	pla			; Restore the length and run into _cvline

_cvline:
	ldx	#'!' | $80	; Vertical line, screen code

cvlinedirect:
	cmp	#$00		; Is the length zero?
   	beq	L9  		; Jump if done
    	sta	tmp1
L1:	txa			; Screen code
   	jsr	putchar		; Write, no cursor advance
   	jsr	newline		; Advance cursor to next line
	dec	tmp1
	bne	L1
L9:	rts