PIC16F1628 Timer0 定时器 控制IO翻转

#include <pic.h>

#define MS20 20000

unsigned char stat = 0;
void interrupt TMR0ISR(void);

void main(void){
TRISB7 = 0;
OPTION_REG = 0x85;  //内部时钟，1/64分频
INTCON = 0xa0;      //全局，Timer0 使能中断
TMR1 = MS20;
RB7 = 1;
while(1){}
}

void interrupt TMR0ISR(void){
T0IF = 0;       //清除
TMR0 = MS20;    //重装
if(stat == 1){
RB7 = 0;
stat = 0;
}else{
RB7 = 1;
stat = 1;
}
}