spwm三种采样方法编程

***************普通 SPWM 程序************************/

#ifndef _NORMAL_SPWM_H

#define _NORMAL_SPWM_H

//SPWM 表结构体 三项公用一个表

typedef struct _SPWM_table

{

Uint16 TableSize; //表大小 即表中所有数据

Uint16 SpwmSize; //SPWM 表大小

volatile Uint16 *p_SPWM_A; //A 相指针

volatile Uint16 *p_SPWM_B; //B 相指针

volatile Uint16 *p_SPWM_C; //C 相指针

Uint16 *p_HeadTable; //表头指针 指向 SPWM 表

}SPWM_TABLE;

extern SPWM_TABLE g_SPWM_Table; //全局SPWM表

void InitSpwm(void);

void StartSpwm(void);

interrupt void ISR_T1UFINT_NORMAL_FUNC(void);

void CalcSpwmWithSym(float32 a/*调制比*/,float32 w_Hz/*调制频率*/,float32 z_Hz/*载波频 率*/);

void CalcSpwmWithImSym(float32 a/*调制比*/,Uint16 w_Hz/*调制频率*/,Uint32 z_Hz/*载波 频率*/);

void CalcSpwmWithArea(float32 a/*调制比*/,Uint16 w_Hz/*调制频率*/,Uint32 z_Hz/*载波频 率*/);

#endif

源文件

#include \"DSP281x.h\"

#include \"SPWM.h\"

#include \"float.h\"

#include \"math.h\"

#define MAX_BUF 400

#define PI 3.1415926

Uint16 g_spwm_data[MAX_BUF]; //表的数据存储

SPWM_TABLE g_SPWM_Table; //全局SPWM表

//SPWM 初始化程序

void InitSpwm(void)

{

g_SPWM_Table.p_HeadTable=g_spwm_data; //指向数据表

g_SPWM_Table.TableSize=MAX_BUF; //存储表的大小

EALLOW;

PieVectTable.T1UFINT=&ISR_T1UFINT_NORMAL_FUNC;

EDIS;

IER|=M_INT2; //开中断2

PieCtrlRegs.PIEIER2.bit.INTx6=1; //开下益中断

EvaRegs.EVAIFRA.bit.T1UFINT=1; //清楚中断标志

PieCtrlRegs.PIEACK.bit.ACK2 = 1; //响应同组中断

}

void StartSpwm(void)

{

EvaRegs.EVAIMRA.bit.T1UFINT = 1; //打开下益 中断

}

//对称规则采样法

void CalcSpwmWithSym(float32 a/*调制比*/,float32 w_Hz/*调制频率*/,float32 z_Hz/*载波频 率*/)

{

Uint16 tmp_PR; //T1 周期值

volatile Uint16 i,n,*p;

float32 m;

m = z_Hz/w_Hz ; //求出载波比

g_SPWM_Table.SpwmSize =(Uint16)m;

tmp_PR=g_T1_Clk/(2*z_Hz); //计算出其周期值

p=g_SPWM_Table.p_HeadTable; //得到数据表头指针

for(i=0;i<(Uint16)m;i++)

{

n=tmp_PR*(0.5-0.5*a*sin((i+0.75)*2*PI/m));

*p=n;

p++;

}

}

//不对称规则采样法

void CalcSpwmWithImSym(float32 a/*调制比*/,Uint16 w_Hz/*调制频率*/,Uint32 z_Hz/*载波 频率*/)

{ Uint16 tmp_PR; //T1 周期值

volatile Uint16 i,n,*p;

float32 m;

m = z_Hz/w_Hz ; //求出载波比

g_SPWM_Table.SpwmSize =(Uint16)m;

tmp_PR=g_T1_Clk/(2*z_Hz); //计算出其周期值

p=g_SPWM_Table.p_HeadTable; //得到数据表头指针

for(i=0;i<(Uint16)m;i++)

{

n=tmp_PR*(0.5-0.25*a*(sin((i+0.25)*2*PI/m)+sin((i+0.75)*2*PI/m)));

*p=n; p++;

}

}

//面积法

void CalcSpwmWithArea(float32 a/*调制比*/,Uint16 w_Hz/*调制频率*/,Uint32 z_Hz/*载波频 率*/)

{

//Uint16 tmp_PR; //T1 周期值

volatile Uint16 i,n,*p;

float32 m,n1,n2;

m=z_Hz/w_Hz; //求出载波比

g_SPWM_Table.SpwmSize =(Uint16)m;

//tmp_PR=g_T1_Clk/(2*z_Hz);//计算出其周期值

p=g_SPWM_Table.p_HeadTable; //得到数据表头指针

n=m;

m/=2; //除去一半 计算半波

n1=(float32)g_T1_Clk/(8.0*m*w_Hz); //计算首相

n2=(float32)g_T2_Clk/(8.0*PI*w_Hz)*a;

for(i=0;i{

*p=n1-n2*(cos(i*PI/m)-cos((i+1)*PI/m));

p++;

}

}

//中断程序

interrupt void ISR_T1UFINT_NORMAL_FUNC(void)

{

static Uint16 cnt=0 ; //计数

EvaRegs.CMPR1 = g_spwm_data[cnt];

cnt++;

if(cnt>=g_SPWM_Table.SpwmSize)

cnt = 0;

EvaRegs.EVAIFRA.bit.T1UFINT=1;

PieCtrlRegs.PIEACK.bit.ACK2 = 1;

EINT;

}