stc12c5a60s2 PWM调速问题

只看该作者 · 2016-10-18 21:16

我使用这款单片机调速时，占空比不对称分布，10%对应转速为0，45%达到最高转速，请问大侠这是什么原因？
程序：#include"stc12c5a60s2.h"
#include "PWM.h"
void send_PWM1(uchar j_temp);
void pwm_init() ;
//static uint step0 = 0;
//static uint step1 = 0;
//void Set_PWM1(uchar duty);

void send_PWM1(uchar j_temp)
{
CR    = 0;
CMOD = 0x00; // CIDL - - - - CPS1 CPS0 ECF  Setup PCA Timer
                     // CPS1 CPS0 = 00, Fosc/12 is PCA/PWM clock
// CPS1 CPS0 = 01, Fosc/2 is PCA/PWM clock    CMOD.1,CMOD.2
                     // 18432000/12/256 = 6000
CL    = 0x00;
CH    = 0x00;
CCAP1L  = j_temp; //Set the initial value same as CCAP0H 00为高电平，FF为低电平
CCAP1H  = CCAP1L; //230 10%
CCAPM1  = 0x42; //0100,0010 Setup PCA module 0 in 8BIT PWM,
CR    = 1;    //启动 PCA/PWM 定时器
}
/*
void pwm_set(unsigned char x,unsigned char y)
{
CCAP0H=x;
CCAP0L=x;
CCAP1H=y;
CCAP1L=y;
}
  */

void pwm_init()    //PWM初始化函数，初始占空比为0
{
CR    = 0;
CMOD = 0x00; // CIDL - - - - CPS1 CPS0 ECF  Setup PCA Timer
CCON = 0x00;                   // CPS1 CPS0 = 00, Fosc/12 is PCA/PWM clock
                     // 11952000/256

CCAPM1 = 0x42;                // 设置为高速模式，允许中断
// IPH = 0x80;             // PCA为最高优先级
//  IP    = 0x80;
CL    = 0x00;
CH    = 0x00;
CR    = 1;    //启动 PCA/PWM 定时器
// EA    = 1;
}