m		equ	3575
n		equ	2925
m_local	equ	6		; stack offset from SP for m 
n_local	equ	4		; stack offset from SP for n
		org	$1000
gcd		ds.w	1
		org	$1500
		lds	#$1500		; set up stack pointer
		ldd	#m		; push m in stack
		pshd
		ldd	#n		; push n in stack
		pshd
		jsr	find_gcd
		std	gcd
		leas	4,sp		; deallocate space used by parameters
		swi
find_gcd	pshx
; ************************************************************************************************************
; The following subroutine uses the iterative division method to compute the gcd of two 16-bit
; integers and return the result in D.
; ************************************************************************************************************
gcd_loop	ldd	n_local,sp	; compute p = n % m
		ldx	m_local,sp	;	"
		idiv			;	"
		cpd	#0
		beq	done
		movw	m_local,sp,n_local,sp
		std	m_local,sp
		bra	gcd_loop
done		ldd	m_local,sp	; retrieve gcd
		pulx			; restore X	
		rts
		end