PWM周期与占空比调节

/****************************************Copyright (c)**************************************************
** Guangzou ZLG-MCU Development Co.,LTD.
** graduate school
**
**
**--------------File Info-------------------------------------------------------------------------------
** File name: main.c
** Last modified Date: 2004-09-16
** Last Version: 1.0
** Descriptions: The main() function example template
**
**------------------------------------------------------------------------------------------------------
** Created by: Chenmingji
** Created date: 2004-09-16
** Version: 1.0
** Descriptions: The original version
**
**------------------------------------------------------------------------------------------------------
** Modified by: Chenxibing
** Modified date: 2005-01-19
** Version:
** Descriptions: 双边沿PWM输出实验。
**
********************************************************************************************************/
#include "config.h"


const uint32 KEY1 = 1 << 16; // P0.16连接KEY1
const uint32 KEY2 = 1 << 17; // P0.16连接KEY1
const uint32 KEY3 = 1 << 18; // P0.16连接KEY1
const uint32 KEY4 = 1 << 19;
const uint32 KEY5 = 1 << 20;
const uint32 BEEP = 1 << 6 ;

const uint32 PWM2 = 1 << 7;
const uint32 PWM4 = 1 << 8;
const uint32 PWM6 = 1 << 9;

const uint32 LED1 = 1 << 18;
const uint32 LED2 = 1 << 19;
const uint32 LED3 = 1 << 20;

int a=1,b=1,c=1,d=1;
uint32 tmp;


/*
*********************************************************************************************************
** 函数名称 ：PWM_Init()
** 函数功能 ：PWM初始化
** 入口参数 ：无
** 出口参数 ：无
*********************************************************************************************************
*/
void DelayNS (uint32 dly)
{
uint32 i;

for ( ; dly>0; dly--)
for (i=0; i<50000; i++);
}
void di()
{
IO0CLR=BEEP;
DelayNS(10);
IO0SET=BEEP;
DelayNS(10);
}
void PWM_Init()
{
tmp = Fpclk / 50;

PWMPR = 0x09; // 对pclk进行分频，PWM计数频率为Fpclk的1/10
PWMMCR = 0x02; // PWMMR0与PWMTC匹配时复位PWMTC
PWMPCR = (1 << 2) | // PWM2双边沿控制
(1 << 4) | // PWM4双边沿控制
(1 << 6) | // PWM6双边沿控制
(1 << 10) | // 使能PWM2输出
(1 << 12) | // 使能PWM4输出
(1 << 14); // 使能PWM6输出
PWMMR0 = tmp; // PWM速率控制/计数初值
/* 设置双边沿脉冲的脉宽和位置 */
PWMMR1 = 0; // PWM2的位置
PWMMR2 = (tmp / 8) * 7;

PWMMR3 = 0; // PWM4的位置
PWMMR4 = (tmp / 8) * 6;

PWMMR5 = 0; // PWM6的位置
PWMMR6 = (tmp / 8) * 5;

PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
}

/*
*************************************************

********************************************************
** 函数名称 ：main()
** 函数功能 ：演示双边沿PWM现象。
** 函数说明 ：需要用多通道示波器或者逻辑分析仪进行观察
*********************************************************************************************************
*/
void PWM_LED()
{

if ((IO0PIN & PWM2) == 0)
{
IO1CLR = LED1;
}
else
{
IO1SET = LED1;
}
if ((IO0PIN & PWM4) == 0)
{
IO1CLR = LED2;
}
else
{
IO1SET = LED2;
}
if ((IO0PIN & PWM6) == 0)
{
IO1CLR = LED3;
}
else
{
IO1SET = LED3;
}
}
void Keyscan()
{
if ((IO0PIN & KEY1) == 0)
{
DelayNS(1);
if ((IO0PIN & KEY1) == 0)
{
di();
a++;
if(a>7) a=1 ;
PWMMR1 = 0; // PWM2的位置
PWMMR2 = (tmp / 8) * a;
PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
while(!(IO0PIN & KEY1));
}
}

if ((IO0PIN & KEY2) == 0)
{
DelayNS(1);
if ((IO0PIN & KEY2) == 0)
{
di();
b++;
if(b>7) b=1 ;
PWMMR1 = 0; // PWM2的位置
PWMMR2 = (tmp / 8) * b;
PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
while(!(IO0PIN & KEY2));
}
}

if ((IO0PIN & KEY3) == 0)
{
DelayNS(1);
if ((IO0PIN & KEY3) == 0)
{
di();
c++;
if(c>7) c=1 ;
PWMMR1 = 0; // PWM2的位置
PWMMR2 = (tmp / 8) * c;
PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
while(!(IO0PIN & KEY3));
}
}
if ((IO0PIN & KEY4) == 0)
{
DelayNS(1);
if ((IO0PIN & KEY4) == 0)
{
di();
d+=1;
if(d>50) d=0;
tmp = Fpclk / (40+d);
PWMMR0 = tmp; // PWM速率控制/计数初值
PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
while(!(IO0PIN & KEY4));
}
}
if ((IO0PIN & KEY5) == 0)
{
DelayNS(1);
if ((IO0PIN & KEY5) == 0)
{
di();
d-=1;
if(d<10) d=50;
tmp = Fpclk / (40+d);
PWMMR0 = tmp; // PWM速率控制/计数初值
PWMLER = 0x7F; // 锁存所有PWM匹配值
PWMTCR = 0x02; // 复位PWMTC
PWMTCR = 0x09; // 使能PWM
while(!(IO0PIN & KEY5));
}
}


}
int main (void)
{

PINSEL0 = (2 << 14) | // P0.7连接PWM2
(2 << 16) | // P0.8连接PWM4
(2 << 18) | // P0.9连接PWM6
(0 << 12);

PINSEL1 = 0x00000000;
PINSEL2 = 0x00000000;
IO1DIR = LED1|LED2|LED3;
IO1SET = LED1|LED2|LED3;
IO0DIR = BEEP;
IO0SET = BEEP;

PWM_Init(); // PWM初始化

while (1)
{
PWM_LED();
Keyscan();
}

return 0;
}
/*************************************************************

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** End Of File
********************************************************************************************************/