www.pudn.com > 双音多频（DTMF）接收器的使用源程序.rar > 9170.asm

include ht48c10.inc 
 
data .section 'data' 
D0	EQU	PA.0 
D1	EQU	PA.1 
D2	EQU	PA.2 
D3	EQU	PA.3 
OE	EQU	PB.0 
DV	EQU	PB.1 
INH	EQU	PB.2 
PWDN	EQU	PB.3 
;----------------------- 
out_code		db	? 
;---------------------------- 
code .section at 0 'code' 
	org	00h 
	jmp	start 
	org	04h 
	reti 
	org	08h 
	reti 
;---------------------------- 
start: 
	clr	intc 
	set	pac 
	clr	pbc 
	set	pbc.1 
	clr	PWDN 
	clr	OE 
scan:	snz	DV 
	jmp	scan 
	set	OE 
	set	pa 
	mov	a,pa 
	mov	out_code,a 
	clr	OE 
	jmp	scan 
end