LCD1602显示PWM频率和占空比单片机源程序Proteus仿真 -

#include<reg52.h>
#include "LCD1602.H"
#define uchar unsigned char
#define uint unsigned int
unsigned int fr=50; //频率 50hz
unsigned char dc=50;//50%占空比
uchar fr_g=0;
uchar fr_s=0;
uchar dc_g=0;
uchar dc_s=0;
/* 配置并启动 PWM，fr-频率，dc-占空比 */
unsigned int high,low;
unsigned long tmp;
unsigned char HighRH = 0; //高电平重载值的高字节
unsigned char HighRL = 0; //高电平重载值的低字节
unsigned char LowRH = 0; //低电平重载值的高字节
unsigned char LowRL = 0; //低电平重载值的低字节
void ConfigPWM();
void ClosePWM();
sbit key1=P3^1; //定义按键位置加占空比
sbit key2=P3^0; //定义按键位置减占空比
sbit PWMOUT = P2^1;
/********************************************************************
//* 名称 : Delay_1ms()
//* 功能 : 延时子程序，延时时间为 1ms * x
//* 输入 : x (延时一毫秒的个数)
//* 输出 : 无
//***********************************************************************/
void Delay_1ms(uint i)//1ms延时
{
uchar x,j;
for(j=0;j<i;j++)
for(x=0;x<=148;x++);
}
void key()
{
if(!key1) //按下相应的按键，数码管显示相应的码值
{ Delay_1ms(10);
if(!key1)
{
if(dc++>=100)dc=100;
}
while(!key1);
}
if(!key2)
{
Delay_1ms(10);
if(!key2)
{
if(dc--<=0)dc=100;
}
while(!key2);
}
}
void ConfigPWM()
{
tmp = (11059200/12) / fr; //计算一个周期所需的计数值
high = (tmp*dc) / 100; //计算高电平所需的计数值
low = tmp - high; //计算低电平所需的计数值
high = 65536 - high + 12; //计算高电平的重载值并补偿中断延时
low = 65536 - low + 12;//计算低电平的重载值并补偿中断延时
HighRH = (unsigned char)(high>>8); //高电平重载值拆分为高低字节
HighRL = (unsigned char)high;
LowRH = (unsigned char)(low>>8); //低电平重载值拆分为高低字节
LowRL = (unsigned char)low;
TMOD &= 0xF0; //清零 T0 的控制位
TMOD |= 0x01; //配置 T0 为模式 1
TH0 = HighRH; //加载 T0 重载值
TL0 = HighRL;
ET0 = 1; //使能 T0 中断
TR0 = 1; //启动 T0
PWMOUT = 1; //输出高电平
}
/* 关闭 PWM */
void ClosePWM()
{
TR0 = 0; //停止定时器
ET0 = 0; //禁止中断
PWMOUT = 1; //输出高电平
}
void main()
{uint i;
LCD1602_Init(1,0,0);//lcd1602初始化
Delay_1ms(100);
LCD1602_DisplayChar(1,2,':');//显示e
LCD1602_DisplayChar(2,1,'d');//显示p
LCD1602_DisplayChar(2,2,':');//显示:
LCD1602_DisplayChar(1,6,'H');//显示t
LCD1602_DisplayChar(1,7,'Z');//显示e
LCD1602_DisplayChar(2,6,'%');//显示t
LCD1602_DisplayChar(1,1,'f');//显示t
TMOD = 0x00;
TL1 = 0xD8;
TH1 = 0xf0;
TR1 = 1; //启动定时器
ET1 = 1; //使能定时器中断
EA = 1; //开总中断
while(1)
{
key();
ConfigPWM();
for (i=0; i<40000; i++);
fr_g = fr%10;
fr_s = fr /10;
dc_g = dc%10;
dc_s = dc/10;
LCD1602_DisplayChar(1,4,fr_s+48);//显示t
LCD1602_DisplayChar(1,5,fr_g+48);//显示e
LCD1602_DisplayChar(2,4,dc_s+48);//显示p
LCD1602_DisplayChar(2,5,dc_g+48);//显示:
}
}
/* T0 中断服务函数，产生 PWM 输出 */
void InterruptTimer0() interrupt 1
{
if (PWMOUT == 1)
{ //当前输出为高电平时，装载低电平值并输出低电平
TH0 = LowRH;
TL0 = LowRL;
PWMOUT = 0;
}
else
{ //当前输出为低电平时，装载高电平值并输出高电平
TH0 = HighRH;
TL0 = HighRL;
PWMOUT = 1;
}
}
void TM1_Isr() interrupt 3 using 1
{
key();
}

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