DSP28335-ePWM

Jacktang

DSP28335-ePWM [复制链接]

#include "DSP28x_Project.h"


// Configure the period for each timer
#define EPWM1_TIMER_TBPRD  3750  // Period register 系统始终为150MHZ，下面的程序进行了4分频，即为37.5MHZ,这样得到的是10KHZ


#define EPWM1_START_CMPA     1900//设置PWM通道A初始占空比
#define EPWM1_START_CMPB     1900//设置PWM通道B初始占空比


void ChangeDuty(Uint16 Duty)//改变占空比函数
{
    if(Duty > EPWM1_TIMER_TBPRD) Duty = EPWM1_TIMER_TBPRD;
    if(Duty < 0) Duty = 0;


    EPwm1Regs.CMPA.half.CMPA = Duty;     // Set compare A value
    EPwm1Regs.CMPB = Duty;               // Set Compare B value
}
void PWM1_Init()//初始化PWM
{
/*首先进行的是PWM1引脚的初始化，因为PWM1的引脚为GPIO0和GPIO1，这两个引脚可以是普通的IO口，也可以复用输出PWM，这里选用复用功能*/
    EALLOW;
    GpioCtrlRegs.GPAPUD.bit.GPIO0 = 0;    // Enable pull-up on GPIO0 (EPWM1A)
    GpioCtrlRegs.GPAPUD.bit.GPIO1 = 0;    // Enable pull-up on GPIO1 (EPWM1B)
    GpioCtrlRegs.GPAMUX1.bit.GPIO0 = 1;   // Configure GPIO0 as EPWM1A复用功能设置，为0代表是普通IO口
    GpioCtrlRegs.GPAMUX1.bit.GPIO1 = 1;   // Configure GPIO1 as EPWM1B
    EDIS;


    EALLOW;
    SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0;      // Stop all the TB clocks
    EDIS;


    // Setup TBCLK
    EPwm1Regs.TBPRD = EPWM1_TIMER_TBPRD - 1;           // 设置周期
    EPwm1Regs.TBPHS.half.TBPHS = 0x0000;           // 这个代表的是相位，不明白什么东西
    EPwm1Regs.TBCTR = 0x0000;                      // Clear counter


    // Set Compare values
    EPwm1Regs.CMPA.half.CMPA = EPWM1_START_CMPA;     // Set compare A value
    EPwm1Regs.CMPB = EPWM1_START_CMPB;               // Set Compare B value


    // Setup counter mode
    EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; //计数模式
    EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE;        // Disable phase loading
    EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV2;       // 这里是进行2分频
    EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV2;          //这里也是2分频


    // Setup shadowing
    EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;   //采用影子寄存器跟新
    EPwm1Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
    EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;  // Load on Zero
    EPwm1Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO;


    // Set actions
    EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;          // Set PWM1A on event A, up count
    EPwm1Regs.AQCTLA.bit.CAD = AQ_SET;           // Clear PWM1A on event A, down count


    EPwm1Regs.AQCTLB.bit.CBU = AQ_SET;             // Set PWM1B on event B, up count
    EPwm1Regs.AQCTLB.bit.CBD = AQ_CLEAR;           // Clear PWM1B on event B, down count


    EALLOW;
    SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1;         // Start all the timers synced
    EDIS;
}
void All_Init()
{
    InitSysCtrl();
    DINT;


    InitPieCtrl();
    IER = 0x0000;
    IFR = 0x0000;
    InitPieVectTable();
    PWM1_Init();


    EINT;   // Enable Global interrupt INTM
    ERTM;   // Enable Global realtime interrupt DBGM
}
Uint16 Duty = 1900;
void main(void)
{


    All_Init();


    while(1)
    {
        ChangeDuty(Duty);
    }
}