pwm.asm

单片机pic16f877 pwm产生及输出

LIST  P=16F877
INCLUDE"P16F877.INC"
ORG      0000H
NOP
BSF      STATUS,RP0 ;选择寄存器OPTION_REG的体为当前体
MOVLW    B'11110000'
MOVWF    TRISC        
MOVLW    .249
MOVWF    PR2
BCF      STATUS,RP0
CLRF     PORTC ;清PORTC
MOVLW    B'00000100' ;开启Timer2，不设预分频和后分频值
MOVWF    T2CON
MOVLW    B'00001100' ;使能PWM
MOVWF    CCP1CON
MOVLW    B'00011001'
MOVWF    CCPR1L
RETURN     
END