Interrupt interfere maximum frequency

Hi all,

I am generating the Famous SPWM with the TMS320F2802x as shown by the picture.

My code is based on a simple way.....

I have a lookup table in the code that contain 200 values from 0 to 200 and my TBPRD value for frequency is 200 (that gives 300kHz)

I use the interrupt routine as seen by the code and I a

const int sineLookup[] = {
        0,
        0,
        0,
        0,
        0,
        1,
        1,
        2,
        2,
        3,
        4,
        5,
        6,
        7,
        8,
        10,
        11,
        12, blabla

      200,

        10,
        8,
        7,
        6,
        5,
        4,
        3,
        2,
        2,
        1,
        1,
        0,
        0,
};

frequency= 200; // define the TBPRD value for frequency 300kHz

interrupt void epwm1_isr(void)
{
    if(i==200)
    {
        i=0;
    }
    if(k==400)
    {
        k=0;
    }
    if(k<=199)
    {
          EPwm1Regs.CMPA.half.CMPA=sineLookup[i];
        EPwm1Regs.CMPB=frequency;
    }
    else
    {
        EPwm1Regs.CMPA.half.CMPA=0;
        EPwm1Regs.CMPB=0;
    }
    i++;
    k++;

    // Clear INT flag for this timer
    EPwm1Regs.ETCLR.bit.INT = 1;
    // Acknowledge this interrupt to receive more interrupts from group 3
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}

void InitEPwm1Example()
{
    CLK_enablePwmClock(myClk, PWM_Number_1);
    EPwm1Regs.TBPRD=frequency;                        // Timer set for frequency (1/Tsw1....kHz)
    EPwm1Regs.TBPHS.half.TBPHS = 0;                    // Phase is 0
   // Setup TBCLK
   EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up down
   EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE;        // Master module
   EPwm1Regs.TBCTL.bit.PRDLD = TB_SHADOW;
   EPwm1Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN;        // Sync flow through
   EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;
   EPwm1Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
   EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;    // Load on CTR=Zero
   EPwm1Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO;    // Load on CTR=Zero
   EPwm1Regs.TBCTL.bit.HSPCLKDIV=TB_DIV1;
   EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;          // Slow just to observe on the scope
   EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;             // Set PWM2A on Zero
   EPwm1Regs.AQCTLA.bit.CAD = AQ_SET;
   EPwm1Regs.AQCTLB.bit.CBU = AQ_CLEAR;           // Set PWM2B on Zero
   EPwm1Regs.AQCTLB.bit.CBD = AQ_SET;
   // Interrupt where the sine wave will be updated
   EPwm1Regs.ETSEL.bit.INTSEL = ET_CTR_PRD;      // Select INT on Zero event
   EPwm1Regs.ETSEL.bit.INTEN = 1;                 // Enable INT
   EPwm1Regs.ETPS.bit.INTPRD = ET_1ST;            // Generate INT on 1st event

}

Now the question....

For some reason the iteration number i and k (here 200 and 400) are directly related to the period Tsw2.

I try now to go from 1kHz to 10kHz and keeping the 200values per half period. But I can't. I HAVE TO use 20 and 40 iterations instead and

the TBPRD can go up to 6.

How can I keep the 400 values and go up to Tsw2=10kHz.

THere must be a way to make a better code to overcome that issue since the Microcontroller can do it.