Chapter 4 Timer Operation

By: Masud-ul-Hasan

Ex4-4: Buzzer Interface

Write a program that sounds the buzzer connected at P1.7 for 1 sec for each 1-to-0 transition detected at P1.6.

ORG 0000H

MOV TMOD, #01H ;16-bit mode

LOOP: JNB P1.6, LOOP ;wait for 1 input

LOOP1: JB P1.6, LOOP1 ;wait for 0 input

SETB P1.7 ;turn buzzer ON

CALL DELAY ;wait for 1 sec

CLR P1.7 ;turn buzzer OFF

SJMP LOOP ;repeat