tricky PWM 100% duty cycle problem in 28335

Hi,

I have configured my PWM timer initilization for inverter which are complementary and PWM outputs are gated (Init_Timer function below). I am using EPWM1 interrupt to process ADC data only.

InitPWMs-1/2/3()
{
// Allow synchronization            
TBCTL.bit.SYNCOSEL  = 0; 
TBCTL.bit.PHSEN     = 0; 
TBCTL.bit.CLKDIV    = 0; 
TBCTL.bit.HSPCLKDIV = 0; 
TBPHS.half.TBPHS    = 0; 
TBCTL.bit.FREE_SOFT = 2;  
                                    
TBPRD              = 5000;
CMPA.half.CMPA     = 2500;
                                    
TBCTL.bit.CTRMODE  = 2;  
TBCTR              = 0;   
                                    
CMPCTL.bit.SHDWAMODE = 0;
CMPCTL.bit.SHDWBMODE = 0;
                                    
// Next PWM is set zero when CTR      reaches zero and moved from Shadow to Active.                       
CMPCTL.bit.LOADAMODE = 0;
CMPCTL.bit.LOADBMODE = 0;
                                    
// Set actions: ACTIVE LOW-HIGH     
AQCTLA.bit.CAU = 0x1;    
AQCTLA.bit.CAD = 0x2;    
                                    
// Setup the deadband - Active high  complementary PWMs               
DBCTL.bit.OUT_MODE = 0x3;
DBCTL.bit.POLSEL   = 2;  
DBCTL.bit.IN_MODE  = 0x0;
DBRED              = 10; 
DBFED              = 10; 

}

With an interface I was able to change the duty cycle varying from 10% to 100% duty cycle and with fixed frequency and could able to see different PWM outputs. I was trying to configure a shorted PWM case which means

EPWM1A-> 12.5V or 100%  EPWM1B -> 0V or 0%
EPWM2A-> 12.5V or 100%. EPWM2B -> 0V or 0%
EPWM3A-> 12.5V or 100%. EPWM3B -> 0V or 0%

or vice versa.

Inorder to acheive this,as per the document. I have set my PWM registers as below. In this case, my PWM just stops and never starts. Only option is to reset the processor and run the PWM. Short()
{
  EPwm1Regs.TBPRD = PWM_PERIOD;
  EPwm2Regs.TBPRD = PWM_PERIOD;
  EPwm3Regs.TBPRD = PWM_PERIOD;

  EPwm1Regs.half.bit.CMPA = 0x0000
  EPwm2Regs.half.bit.CMPA = 0x0000
  EPwm3Regs.half.bit.CMPA = 0x0000
}

Can I acheive this with this configuration or Am I missing some thing or IS THERE ANY MAGIC?  I have referred EPWM document as well as SPRAA1 doc also. Replies greatly appreciated.

Thanks alot,

Regards,

Kuldeep