pwm_test1.c

Philip的新款单片机p89v51的PWM输出的应用示例

#include <stdio.h>
#include <reg51.h>
#include <math.h>
#include <absacc.h>

#define uchar unsigned char
#define uint unsigned int
/*--------------------------parameter setting-----------------------*/
#define XtalFreq (11.059200)//Crystal Frequence

#define FALSE 0
#define TRUE 1
/*--------------------------sfr setting-----------------------*/
sfr CCAPM0=0xDA;//PCA module 0 mode
sfr PCACL=0xE9;//PCA timer Low BYTE

sfr CCAP0H=0xFA;//module 0 get High BYTE 
sfr CCAP0L=0xEA;//module 0 get Low BYTE 

sfr CMOD=0xD9;//PCA module timer mode
sfr CCON=0xD8;//PCA module timer control

sbit CR=0xDE;//The PCA Start Count
sbit CEX0=0x93;//PWM output CEX0 output P1.3
/*-------------------------------main-------------------------------*/
void main()
{
	int i;
	TMOD=0x22;
	/*-----------------------serrial show----------------------*/
	SCON=0x50;
	TI=1;//the same to SCON=0x52;
	//TMOD=0x20;//T1:8bit; T0:16bit
	PCON|=0x80;
	TL1=0;
	TH1=0xe8;//using the 1200bps//(unsigned int)(256-((XtalFreq/BaudRate)/192));
	//TR0=1;//start T0
	TR1=1;//start T1
	printf("/nThe Test of the PWM Show:/n");
	printf("The PWM OUTPUT is :/n");
	/*-----------------------PWM----------------------*/
	
	TL0=0xf4;
	TH0=0xf4;
	
	CCAP0L=0x7f;
	CCAP0H=0x7f;//using for the control of the PWM pulse
	//PCACL=0x7F;
	CMOD=0x84;//using the T0 overflow for the Count Pulse,none Interupt,none WDOG/remain count
    CCAPM0=0x42;//model 0 work state
	TR0=1;
	CR=1;//start the PCA Counter
	//do
	//{
	//	if(CEX0==1)
	//		printf("1 ");
	//	else
	//		printf("0 ");
	//}
	while(1);
}