二、ePWM所需配置流程与内容（每个周期进入一次中断） Step1:初始化GPIO-ePWM2     InitEPwm2Gpio(); Step2:初始化PIE中断向量表，（使用中断方式接收上位机数据）     EALLOW;   //寄存器EALLOW保护     PieVectTable.EPWM2_INT= &PWM2TickIsr;//初始化PIE中断向量表     EDIS;   //禁止写如EALLOW保护的寄存器 Step3:初始化ePWM void EPwmSetup() {     EPwm2Regs.TBSTS.all=0;     EPwm2Regs.TBPHS.half.TBPHS =0;//设置相位寄存器置零     EPwm2Regs.TBCTR=0;//PWM时间基准（TB）计数器清零     EPwm2Regs.CMPCTL.all=0x50;        // Immediate mode for CMPA and CMPB     EPwm2Regs.CMPA.half.CMPA =SP/2;//比较器A的=SP/2个TBCLK---低电平有效-----调整占空比50%     EPwm2Regs.CMPB=0;//比较器B=SP/4个TBCLK----低电平有效、
    EPwm2Regs.AQCTLA.all=0x60;// EPWMxA = 1 when CTR=CMPA and counter inc                                    // EPWMxA = 0 when CTR=CMPA and counter dec     EPwm2Regs.AQCTLB.all=0x600;//EPWMxB = 1 when CTR=CMPB and counter inc                               // EPWMxB= 0 when CTR=CMPB and counter dec     EPwm2Regs.AQSFRC.all=0;     EPwm2Regs.AQCSFRC.all=0;       EPwm2Regs.TZSEL.all=0;     EPwm2Regs.TZCTL.all=0;     EPwm2Regs.TZEINT.all=0;     EPwm2Regs.TZFLG.all=0;     EPwm2Regs.TZCLR.all=0;     EPwm2Regs.TZFRC.all=0;     EPwm2Regs.DBCTL.all=0x23;         //死区设置 // EPWMxB is inverted     EPwm2Regs.DBRED=0;     EPwm2Regs.DBFED=0;       EPwm2Regs.ETSEL.all=9;            // Interrupt when TBCTR = 0x0000     EPwm2Regs.ETPS.all=1;             // Interrupt on first event       EPwm2Regs.ETFLG.all=0;     EPwm2Regs.ETCLR.all=0;     EPwm2Regs.ETFRC.all=0;       EPwm2Regs.PCCTL.all=0;//斩波器控制寄存器       EPwm2Regs.TBCTL.all=0x0010+TBCTLVAL;          // Enable Timer     EPwm2Regs.TBPRD=SP; //周期=SP个TBCLK   }   interrupt void PWM2TickIsr(void) //Interrupts once per ePWM period {     Pulse_count++;     PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;// 第三组中断响应     EPwm2Regs.ETCLR.bit.INT=1;  //清除ePWM2中断 } Step4：使能所需的中断 //使能所需的中断     PieCtrlRegs.PIECTRL.bit.ENPIE=1; //使能PIE模块 //ePWM2        PieCtrlRegs.PIEIER3.bit.INTx2 = 1; // Enable TINT0in the PIE: Group 3 interrupt 2, ePWM2     IER|= M_INT3;// 使能CPU的第三组中断--ePWM2