[TMS320F28027] Piccolo 시리즈 PWM테스트

[TMS320F28027] Piccolo 시리즈 PWM테스트

TI의 Piccolo 시리즈중 저렴한 TMS320F28027은 8채널의 ePWM(enhanced PWM Modules)이 있다.
GPIO0/EPWM1A
GPIO1/EPWM1B/COMP1OUT
GPIO2/EPWM2A
GPIO3/EPWM2B/COMP2OUT
GPIO4/EPWM3A
GPIO5/EPWM3B/ECAP1
GPIO6/EPWM4A/EPWMSYNCI/EPWMSYNCO
GPIO7/EPWM4B/SCIRXDA


테스트를 위해 EPWM1에 연결하여 간단히 LED램프제어 하는 예제를 테스트 해 보았다.

TMS320F28027 ePWM테스트 동영상

TMS320F28027 ePWM 제어 드라이버 코드

void SetPwm1Period(unsigned int Frequency, unsigned int Period)
{
    EPwm1Regs.TBPRD = Frequency;
    EPwm1Regs.CMPA.half.CMPA = Frequency-(Frequency*(Period/100.0));
}

void HRPWM1_Config(unsigned int period)
{
   EPwm1Regs.TBPRD = period;                        // Set timer period
   EPwm1Regs.TBPHS.half.TBPHS = 0x0000;           // Phase is 0
   EPwm1Regs.TBCTR = 0x0000;                      // Clear counter

   // Setup TBCLK
   EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up
   EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE;        // Disable phase loading
   EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1;       // Clock ratio to SYSCLKOUT
   EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;

   EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;    // Load registers every ZERO
   EPwm1Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
   EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;
   EPwm1Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO;   

   // Setup compare
   EPwm1Regs.CMPA.half.CMPA = period / 2;
  
   // Set actions
   EPwm1Regs.AQCTLA.bit.CAU = AQ_SET;             // Set PWM1A on Zero
   EPwm1Regs.AQCTLA.bit.CAD = AQ_CLEAR;
  
   EPwm1Regs.AQCTLB.bit.CAU = AQ_CLEAR;          // Set PWM1A on Zero
   EPwm1Regs.AQCTLB.bit.CAD = AQ_SET;
  
   // Active Low PWMs - Setup Deadband
   EPwm1Regs.DBCTL.bit.OUT_MODE = DB_FULL_ENABLE;
   EPwm1Regs.DBCTL.bit.POLSEL = DB_ACTV_LO;
   EPwm1Regs.DBCTL.bit.IN_MODE = DBA_ALL;
   EPwm1Regs.DBRED = 10;
   EPwm1Regs.DBFED = 10;
  
  
   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
    GpioCtrlRegs.GPAMUX1.bit.GPIO1 = 1;   // Configure GPIO1 as EPWM1B
  
    EDIS;
}

TMS320F28027 ePWM 예제 소스코드

void main(void)
{
 unsigned int cnt = 0;
 int flag = 0;

//DSP System Initialize
 SystemInit();

 DebugInit(BAUD_115200);
 DebugPrint("LED Test\r\n");

 //LED Initialize
 Led1Init();
 Led1On();

 InitPwm();
 SetPwm1Period(PWM_10KHZ, 50);

 while(1)
 {
  if(flag)cnt--;
  else cnt++;

  if(cnt==100)flag = 1;
  else if(cnt == 0)flag=0;

  SetPwm1Period(PWM_100HZ, cnt);
  Delay(cnt/2);
 }
}