基于Proteus的直流电机调速c程序
#include<reg51.h>
#define Tpwm 0xfc18//PWM周期对应的计数值1ms，基于12MHz晶振
unsigned int duty[]={0,/*0*/
0xff9c/*100us*/,0xff38/*200us*/,0xfed4/*300us*/,\
0xfe70/*400us*/,0xfe0c/*500us*/,0xfda8/*600us*/,\
0xfd44/*700us*/,0xfce0/*800us*/,0xfc7c/*900us*/,\
0xfc18/*1000us*/};//PWM高电平时间
unsigned char i=0;
sbit P32 = P3^2;
sbit P33 = P3^3;
sbit PWMOUT = P2^0;
sbit PWMIN1 = P2^1;
sbit PWMIN2 = P2^2;
bit flag = 1;//PWM输出电平状态，1为输出高电平时间，0为输出低电平时间
void delay10ms(int n);
void main(void)
{
PWMOUT = 0;//初始化L293D ，停止电机
PWMIN1 = 0;
PWMIN2 = 1;
EA = 1; //开总中断
IT0 = 1; //中断方式为跳变
IT1 = 1;
EX0 = 1; //打开外部中断0
EX1 = 1; //打开外部中断1
ET0 = 1; //开定时器0中断允许
TMOD = 0x01; //设置定时方式
while(1) //等待中断
{
/*在此可以实现其它任务*/
}
}
//10ms延时函数
void delay10ms(int n)
{
int i=0,j;
while(n--)
{
for(i=0;i<10;i++)
{
for(j = 0; j < 125; j++);
}
}
}
void keySpeeddownISR() interrupt 0 //按键中断服务程序
{
EA = 0; //关中断
delay10ms(2); //延时消抖
if (!P32) //确认按键按下，滤除键盘抖动干扰
{//减少PWM高电平时间
if(i>0)
i--;
if((TR0=1) && (i == 0))
{
TR0 = 0;
PWMOUT = 0;
}
}
EA = 1;
}
void keySpeedupISR() interrupt 2 //按键中断服务程序
{
EA = 0; //关中断
delay10ms(2); //延时消抖
if (!P33) //确认按键按下，滤除键盘抖动干扰
{//增加PWM高电平时间
if(i<=10)
i++;
if((TR0 == 0) && (i > 0))
{//启动PWM,电机顺时针旋转
PWMIN1 = 0;
PWMIN2 = 1;
PWMOUT = 1;
TH0 = duty[i]>>8;
TL0 = duty[i]&0xff;
TR0 = 1;
flag = 1;
}
}
EA = 1;
}
void T0ISR() interrupt 1 //定时器0中断服务程序
{
EA = 0; //关中断
if(flag)
{//高电平时间结束，输出低电平补齐PWM周期
PWMOUT = 0;
TH0 = (65535-(duty[i]-Tpwm))>>8;
TL0 = (65535-(duty[i]-Tpwm))&0xff;
flag = 0;
}else
{//周期结束
PWMOUT = 1;
TH0 = duty[i]>>8;
TL0 = duty[i]&0xff;
flag = 1;
}
EA = 1;
}
仅供参考。学单片机还需自己多多思考和练习
