ADSP-21569 GPIO output speed Limit

Hi,

I'm testing the GPIO function of ADSP-2156x_EZKIT. (PB_03 LED out Toggle)

output reflash rate is very slow. (about 40 nsec)

clock setting is (CCLK: 1000 MHz, SYSCLK: 500 MHz, SCLK0: 125 MHz, SCLK1: 250 MHz, DCLK: 666 MHz, OCLK: 125 MHz)

I can't understand, why the GPIO output speed is slow.

below is my test source

please help me..

//##############################################################################
int main(int argc, char *argv[])
{

    adi_pwr_cfg0_init(); // CLKs Init
/*
    adi_pwr_GetFreq(ADI_PWR_CGU0,fclkstruct0);
    printf("\nCGU Number = %d", 0);
    printf("\n------------------------------");
    printf("\nPLLCLK = %d Hz", (*fclkstruct0.fpllclk) );
    printf("\nCCLK = %d Hz", (*fclkstruct0.fcclk) );
    printf("\nSYSCLK = %d Hz", (*fclkstruct0.fsysclk) );
    printf("\nSCLK0 = %d Hz", (*fclkstruct0.fsclk0) );
    printf("\nSCLK1 = %d Hz", (*fclkstruct0.fsclk1));
    printf("\nDCLK = %d Hz", (*fclkstruct0.fdclk) );
    printf("\nOCLK = %d Hz", (*fclkstruct0.foclk) );
    printf("\n------------------------------\n\n");

    adi_pwr_SetClkOutSelectRegister(ADI_PWR_CGU0, ADI_PWR_CLKOUT_CGU0_SCLK0); // 125 MHz Clock Out
*/

    adi_initComponents(); // MUX & FER Init

    ConfigSoftSwitches(); // MCP23017 (TWI2 to I/O) Init


    adi_gpio_PortInit(ADI_GPIO_PORT_B, ADI_GPIO_PIN_3, ADI_GPIO_DIRECTION_OUTPUT, true); // PB_03 -> LED7 Init

    while(1)
    {
        *pREG_PORTB_DATA_TGL = ADI_GPIO_PIN_3;
    }

    return 0;
}

//##############################################################################

@ PORT OUT asm source is

154                         *pREG_PORTB_DATA_TGL = ADI_GPIO_PIN_3;
.P44L5:
001c17d0:      i4=0x8;
001c17d2:     dm (0x310040b4)=i4;
001c17d5:     jump (pc,-0x5);



.
[edited by: bk92034 at 5:46 AM (GMT 0) on 7 Nov 2019]