stk		START	0
		JSUB	stackinit

		LDA	#1
		STA	@stkptr
		JSUB	stackpush

		LDA	#2
		STA	@stkptr
		JSUB	stackpush

		LDA	#3
		STA	@stkptr
		JSUB	stackpush

		JSUB	stackpop
		LDA	@stkptr
		STA	val3

		JSUB	stackpop
		LDA	@stkptr
		STA	val2

		JSUB	stackpop
		LDA	@stkptr
		STA	val1

halt		J	halt

stackpush	STA	temp
		LDA	stkptr
		ADD 	#3
		STA	stkptr
		LDA	temp
		RSUB

stackpop	STA  	temp
		LDA  	stkptr
		SUB  	#3     
		STA  	stkptr
		LDA  	temp
		RSUB

stackinit	STA	temp
		LDA	#stack
		STA	stkptr
		LDA	temp
		RSUB

stkptr		RESW	1
temp		RESW	1
val1		RESW	1
val2		RESW	1
val3		RESW	1
stack		RESW	50
		END		stk