How to mask pwm outputs

Shivraj,

I would recommend looking at the following post:
http://e2e.ti.com/support/microcontrollers/c2000/f/171/p/250345/876885.aspx#876885

You would create a PWM as in some of the examples in controlSUITE.  You'd then use one of the suggestions in the linked post to stop the PWM signal over some length of time. 
(\controlSUITE\device_support\f2833x\v133\DSP2833x_examples_ccsv4\)

I generally prefer the trip zone (TZ) method.


Thank you,
Brett

HI shivraj,

Steps to create ePWM for 10ms ON and OFF

1. Configure a ePWMx.

2. Configure a Timer interrupt.

3. In the timer ISR enable and disable the GPIOMUX reg.

 e.g  

if(GpioG1CtrlRegs.GPAMUX1.bit.GPIO0 == 1) {
EALLOW;
GpioG1CtrlRegs.GPAMUX1.bit.GPIO0 = 0;
EDIS;
}else{
EALLOW;
GpioG1CtrlRegs.GPAMUX1.bit.GPIO0 = 1;
EDIS;
}

=========================================================================================================

Configuration of ePWM output:

// Time-base registers
EPwm1Regs.TBPRD = PERIOD; // Set EPWM timer period
EPwm1Regs.TBCTR = 0; // Time-Base Counter Register
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count-up mode: used for asymmetric PW
// Set TBCLK frequency
EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1; // TBCLK = SYSCLKOUT
EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;
EPwm1Regs.AQCTLA.all = 6; // ZRO = set, PRD = clear
EPwm1Regs.AQCTLB.all = 6; // ZRO = set, PRD = clear

=========================================================================================================

Configuration of Timer0:

void InitCpuTimers(void)
{
CpuTimer0.RegsAddr = &CpuTimer0Regs;

CpuTimer0Regs.PRD.all = 0xFFFFFFFF;

CpuTimer0Regs.TPR.all = 0;
CpuTimer0Regs.TPRH.all = 0;

CpuTimer0Regs.TCR.bit.TSS = 1;

CpuTimer0Regs.TCR.bit.TRB = 1;

CpuTimer0.InterruptCount = 0;

}

===================================================================

void ConfigCpuTimer(struct CPUTIMER_VARS *Timer, float Freq, float Period)
{
Uint32 temp;

// Initialize timer period:
Timer->CPUFreqInMHz = Freq;
Timer->PeriodInUSec = Period;
temp = (long) (Freq * Period);
Timer->RegsAddr->PRD.all = temp;

// Set pre-scale counter to divide by 1 (SYSCLKOUT):
Timer->RegsAddr->TPR.all = 0;
Timer->RegsAddr->TPRH.all = 0;

// Initialize timer control register:
Timer->RegsAddr->TCR.bit.TSS = 1; // 1 = Stop timer, 0 = Start/Restart
// Timer
Timer->RegsAddr->TCR.bit.TRB = 1; // 1 = reload timer
Timer->RegsAddr->TCR.bit.SOFT = 0;
Timer->RegsAddr->TCR.bit.FREE = 0; // Timer Free Run Disabled
Timer->RegsAddr->TCR.bit.TIE = 1; // 0 = Disable/ 1 = Enable Timer
// Interrupt
// Reset interrupt counter:
Timer->InterruptCount = 0;
}

=========================================================================================================

Main function:

#define PERIOD 50
#define C28_FREQ 100 //CPU frequency in MHz

void ConfigEpwm1( void );
interrupt void cpu_timer0_isr(void);

// Global variables used in this example:
Uint16 LoopCount;
Uint16 ConversionCount;

main()
{

// Step 1. Initialize System Control for Control and Analog Subsytems
// Enable Peripheral Clocks
// This example function is found in the F28M36x_SysCtrl.c file.
InitSysCtrl();

// If project is linked into flash, copy critical code sections to RAM.
#ifdef _FLASH
memcpy(&RamfuncsRunStart, &RamfuncsLoadStart, (size_t)&RamfuncsLoadSize);
#endif

EDIS;

// Step 2. Initialize GPIO:
// This example function is found in the F28M36x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
InitGpio(); // Skipped for this example
EALLOW;
GpioG1CtrlRegs.GPADIR.bit.GPIO0 = 1; // Set as output
GpioG1CtrlRegs.GPAMUX1.bit.GPIO0 = 1; // Select EPWM1SOCA as driving source
GpioG1CtrlRegs.GPADIR.bit.GPIO1 = 1; // Set as output
GpioG1CtrlRegs.GPAMUX1.bit.GPIO1 = 1; // Select EPWM1SOCB as driving source
GpioG1CtrlRegs.GPCDIR.bit.GPIO70 = 1; //set PC6_GPIO70 as output
EDIS;

// Step 3. Clear all interrupts and initialize PIE vector table:
// Disable CPU interrupts
DINT;

// Initialize the PIE control registers to their default state.
// The default state is all PIE interrupts disabled and flags
// are cleared.
// This function is found in the F28M36x_PieCtrl.c file.
InitPieCtrl();

// Disable CPU interrupts and clear all CPU interrupt flags:
IER = 0x0000;
IFR = 0x0000;

// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in F28M36x_DefaultIsr.c.
// This function is found in F28M36x_PieVect.c.
InitPieVectTable();

// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.
EALLOW; // This is needed to write to EALLOW protected registers
PieVectTable.TINT0 = &cpu_timer0_isr;
EDIS; // This is needed to disable write to EALLOW protected registers

// Step 4. Initialize the Device Peripheral. This function can be
// found in F28M36x_CpuTimers.c
InitCpuTimers(); // For this example, only initialize the Cpu Timers

ConfigEpwm1();
// Configure CPU-Timer 0, 1, and 2 to interrupt every second:
// C28_FREQ in MHz, 1 second Period (in uSeconds)

ConfigCpuTimer(&CpuTimer0, C28_FREQ, 10);
// To ensure precise timing, use write-only instructions to write to the entire
// register. Therefore, if any
// of the configuration bits are changed in ConfigCpuTimer and InitCpuTimers (in
// F28M36x_CpuTimers.h), the
// below settings must also be updated.

CpuTimer0Regs.TCR.all = 0x4000; // Use write-only instruction to set TSS bit

// Step 5. User specific code, enable interrupts:

// Enable CPU int1 which is connected to CPU-Timer 0, CPU int13
IER |= M_INT1;

// Enable TINT0 in the PIE: Group 1 interrupt 7
PieCtrlRegs.PIEIER1.bit.INTx7 = 1;

// Enable global Interrupts and higher priority real-time debug events:
EINT; // Enable Global interrupt INTM
ERTM; // Enable Global realtime interrupt DBGM

LoopCount = 0;
ConversionCount = 0;

// Wait for ADC interrupt
for(;;)
{
LoopCount++;
}

}

=========================================================================================================

Please select " Verify answer" if its work fine.

Regards 

Thirumoorthy.R