; arithmetic String Manipulation Example

; Assembly language which converts a string from
; upper case ascii to lower case ascii by adding 32

$BASE 10T  	    ; convert the default base to
                    ; decimal (was hex)

	ldx #string ; x points to the start of the
                    ; string

	ldaa 0,x    ; load M[X+0] into "A"
loop:
	adda #32    ; set bit 5 by adding 32
        staa 0,x    ; save new char where it was
	inx         ; go to the next character
	ldaa 0,x    ; load the next character
	cmpa #46    ; is the character a "."?
	bne  loop   ; go back to "loop" if the
                    ; character is not a '.'
        	    ; otherwise, we are done, so
                    ; clear the stop bit

	tpa         ; Get the CCR into A
	anda #$7f   ; clear the stop bit
	tap         ; put it back in the CCR

	stop        ; stop works now so stop.


;;;===================================

string: DB 'HELLO WORLD.'

        org $fffe
reset:  DW 0000