pic16f716在spwm半桥输出

pic16f716单片机spwm输出模式半桥状态，可是有相波形的第一个脉宽不对啊（如图一），图二是另外一相波形，这个是我想要的，不明白第一个为什么，

图一

还有一个问题为什么我设置的死去时间的一个单位时间是:SPWM的周期时间啊，而不是datasheet上讲的是Fosc/4

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wubaoxue

LV.1

2013-10-12 15:32

这个是我的半桥程序，有哪位大侠能帮我看看啊！！！，这波形怎么会是上面这个样子，还有死去时间，我实在无语了！！

//spwm调制，逆变器,

#include

#define uchar unsigned char

#define uint unsigned int

__CONFIG(0X3F32);

const uchar sinTab[200]={ //调制度M=0.9;正弦波代码数组

0,1,2,3,4,5,6,7,8,10,

11,12,13,14,15,16,17,18,19,20,

21,22,23,24,25,26,27,28,29,30,

31,32,33,33,34,35,36,37,38,39,

40,41,41,42,43,44,45,45,46,47,

48,48,49,50,51,51,52,53,53,54,

55,55,56,56,57,58,58,59,59,60,

60,61,61,62,62,62,63,63,64,64,

64,65,65,65,65,66,66,66,66,66,

67,67,67,67,67,67,67,67,67,67,

67,67,67,67,67,67,67,67,67,

67,66,66,66,66,66,65,65,65,65,

64,64,64,63,63,62,62,62,61,61,

60,60,59,59,58,58,57,56,56,55,

55,54,53,53,52,51,51,50,49,48,

48,47,46,45,45,44,43,42,41,41,

40,39,38,37,36,35,34,33,33,32,

31,30,29,28,27,26,25,24,23,22,

21,20,19,18,17,16,15,14,13,12,

11,10,8,7,6,5,4,3,2,1,0

};

/*基波50Hz,载波20KHz,半周期内的采样点数为100，则pwm的周期=1/20ms=50us*/

/*SPWM初始化*/

uchar B_D=0,i;

void init()

{

TRISB=0X28; //

PR2=149; //SPWM为50uS=150*4*(1/12)

CCP1CON=0XBd; //spwm模式选择,半桥1011,1101,A、c高有效，b、d低有效

CCPR1L=0; //占空比为0

PWM1CON=0X00; //

TMR2IF=0;

T2CON=0X04; //不分频，使能TMR2

}

void tmr2()

{

if(TMR2IF)

{

if(i==200)

{

i=0;

B_D=!B_D;

}

if(B_D)

{

TRISB=0X20; //B...C

}

else

{

TRISB=0X08; //D...A

}

PR2=149; //SPWM为50uS=150*4*(1/12)

CCPR1L=sinTab[i];

TMR2IF=0;

i++;

}

void main ()

{

init();

while(1)

{

tmr2();

}

danielchen003

LV.1

2013-10-21 14:57

@wubaoxue

这个是我的半桥程序，有哪位大侠能帮我看看啊！！！，这波形怎么会是上面这个样子，还有死去时间，我实在无语了！！//spwm调制，逆变器,#include#defineucharunsignedchar#defineuintunsignedint__CONFIG(0X3F32);constucharsinTab[200]={ //调制度M=0.9;正弦波代码数组0,1,2,3,4,5,6,7,8,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,33,34,35,36,37,38,39,40,41,41,42,43,44,45,45,46,47,48,48,49,50,51,51,52,53,53,54,55,55,56,56,57,58,58,59,59,60,60,61,61,62,62,62,63,63,64,64,64,65,65,65,65,66,66,66,66,66,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,67,66,66,66,66,66,65,65,65,65,64,64,64,63,63,62,62,62,61,61,60,60,59,59,58,58,57,56,56,55,55,54,53,53,52,51,51,50,49,48,48,47,46,45,45,44,43,42,41,41,40,39,38,37,36,35,34,33,33,32,31,30,29,28,27,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,8,7,6,5,4,3,2,1,0};/*基波50Hz,载波20KHz,半周期内的采样点数为100，则pwm的周期=1/20ms=50us*//*SPWM初始化*/ucharB_D=0,i;voidinit(){TRISB=0X28;//PR2=149;//SPWM为50uS=150*4*(1/12)CCP1CON=0XBd; //spwm模式选择,半桥1011,1101,A、c高有效，b、d低有效CCPR1L=0;//占空比为0PWM1CON=0X00;//TMR2IF=0;T2CON=0X04;//不分频，使能TMR2}void tmr2(){if(TMR2IF){if(i==200){i=0;B_D=!B_D;}if(B_D){TRISB=0X20;//B...C}else{TRISB=0X08;//D...A}PR2=149;//SPWM为50uS=150*4*(1/12)CCPR1L=sinTab[i];TMR2IF=0;i++;}}voidmain(){init();while(1){ tmr2();}}

半桥SPWM上下桥臂的驱动应该是互补的吧....