单片机+舵机+PWM+独立按键

#include <reg52.h> sbit Pwm_val = P1^0; sbit k1 = P3^0; sbit k2 = P3^1; sbit LED = P1^1; unsigned char counter=0; //计数值 unsigned char angle=0; //旋转角度 void Timer0_Init()//定时器0初始化 { TMOD = 0X01; //设置定时器模式 TH0 = (65536-500)/256; //设置定时器初值 TL0 = (65536-500)%256; ET0 = 1; //允许定时器0中断 TR0 = 1; //启动定时器0 EA = 1; //打开总中断 } void Timer0_Int() interrupt 1//定时器0的中断服务函数 { TR0 = 0; //关闭定时器0 TH0 = (65536-500)/256; //设置定时器初值 TL0 = (65536-500)%256; counter++; if(counter >= 40) //20ms到了 { counter = 0; } if(counter < angle) { Pwm_val = 1; } else { Pwm_val = 0; } TR0 = 1; //启动定时器0 } void Delay_xms(unsigned char t)//延时xms { unsigned char i,j; for(i=t;i>0;i--) for(j=123;j>0;j--); } void Zero() //舵机归中 { angle = 3; } void key_scan() { if(k1 == 0) { Delay_xms(10); if(k1 == 0) { counter = 0; angle = angle + 1; LED = 1; while(!k1); } } if(k2 == 0) { Delay_xms(10); if(k2 == 0) { counter = 0; angle = angle - 1; LED = 0; while(!k2); } } } void main() { Timer0_Init(); Zero(); while(1) { key_scan(); if(angle>5)angle=5; if(angle<1)angle=1; } }