51單片機(jī)PWM精確輸出按鍵可調(diào)輸出周期占空比1602顯示程序

ID:455286 · 發(fā)表于 2018-12-26 23:59

51PWM精確輸出按鍵可調(diào)輸出周期占空比，誤差可以達(dá)到零點(diǎn)幾以內(nèi)。1602顯示當(dāng)前輸出PWM周期占空比。

單片機(jī)源程序如下:

#include <reg51.h>
#include <intrins.h>
#include "lcd.h"
unsigned char code ASCII[10] = {'0','1','2','3','4','5','6','7','8','9'};
unsigned char period[]="Period:";
unsigned char high[]="Duty:";
unsigned char disbuff[10];
unsigned int peri =1000;
unsigned int value=600; //初始占空比為60% 周期為1ms
sbit PWM=P2^1; //PWM輸出口
sbit K1=P1^0; //占空比增加鍵
sbit K2=P1^1; //占空比減小鍵
sbit K3=P1^2; //周期增加鍵
sbit K4=P1^3; //周期減小鍵
void TimerInit()
{
TMOD=0X11;
TH0 = (unsigned int)(65536-peri)/256;
TL0 = (unsigned int)(65536-peri)%256; //1ms周期
TH1 = (unsigned int)(65536-value)/256;
TL1 = (unsigned int)(65536-value)%256; //600us高電平時(shí)間
ET0=1;//打開(kāi)定時(shí)器0中斷允許
ET1=1;
TR0=1;//打開(kāi)定時(shí)器
TR1=0;//打開(kāi)定時(shí)器
EA=1;//打開(kāi)總中斷
}
void delay(unsigned int i)
{
while(i--);
}
void Key_Scan()
{
if(K1==0)
{
delay(1000);
if(K1==0)
{
value+=20; //占空比增加
if(value>=peri)
{
value=peri;
}
}
while(!K1);
}
if(K2==0)
{
delay(1000);
if(K2==0)
{
value-=20; //占空比減小
if(value<=0)
{
value=0;
}
}
while(!K2);
}
if(K3==0)
{
delay(1000);
if(K3==0)
{
peri+=100;//周期增加100us
}
while(!K3);
}
if(K4==0)
{
delay(1000);
if(K4==0)
{
peri-=100; //周期減小100us
}
while(!K4);
}
}
void main(void)
{
InitLcd1602();
TimerInit();
while(1)
{
int zhanbi;
Key_Scan();
LcdShowStr(0,0,period); //顯示周期
LcdShowStr(0,1,high); //顯示占空比
disbuff[0]=peri/10000;
disbuff[1]=peri%10000/1000;
disbuff[2]=peri%1000/100;
disbuff[3]=peri%100/10;
disbuff[4]=peri%10;
DisplayOneChar(7,0,ASCII[disbuff[0]]);
DisplayOneChar(8,0,ASCII[disbuff[1]]);
DisplayOneChar(9,0,ASCII[disbuff[2]]);
DisplayOneChar(10,0,ASCII[disbuff[3]]);
DisplayOneChar(11,0,ASCII[disbuff[4]]);
DisplayOneChar(12,0,'u');
DisplayOneChar(13,0,'s');
zhanbi=(value/10*100)/(peri/10);
disbuff[0]=zhanbi/10;
disbuff[1]=zhanbi%10;
DisplayOneChar(7,1,ASCII[disbuff[0]]);
DisplayOneChar(8,1,ASCII[disbuff[1]]);
DisplayOneChar(9,1,'%');
}
}
void Time0(void) interrupt 1
{
TH0 = (unsigned int)(65536-peri+30)/256; //加30彌補(bǔ)中斷事件，具體可通過(guò)調(diào)節(jié)數(shù)值達(dá)到彌補(bǔ)效果
TL0 = (unsigned int)(65536-peri+30)%256; //通過(guò)改變peri改變周期大小
PWM=1;
TR1=1;
}
void Time1(void) interrupt 3
{
TH1 = (unsigned int)(65536-value+20)/256; //加20彌補(bǔ)中斷事件，具體可通過(guò)調(diào)節(jié)數(shù)值達(dá)到彌補(bǔ)效果
TL1 = (unsigned int)(65536-value+20)%256; //通過(guò)改變value改變占空比
PWM=0;
TR1=0;
}
//經(jīng)示波器測(cè)定占空比誤差百分之一左右通過(guò)自己調(diào)節(jié)彌補(bǔ)值大小可以達(dá)到誤差百分之零點(diǎn)五以下