Trying to understand clocks

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Anonymous
Not applicable

I made a very simple test jig , where the system clock is set to 48MHz, no dividers.  I am simply toggling a pin.

   

int main()
{
    /* Place your initialization/startup code here (e.g. MyInst_Start()) */

   

    /* CyGlobalIntEnable; */ /* Uncomment this line to enable global interrupts. */
    for(;;)
    {
        SCLK_Write(0x01);
        SCLK_Write(0x00);
        /* Place your application code here. */
    }
}

   

but I am not seeing the pin toggle at nearly the rate I would expect given the system clock speed.  Frequency of the output is 350kHz, so it is 48MHz/350kHz = 137 off from 48MHz.  I have a hard time believing that there are so many cycles per instruction.   Rather, I am thinking something is not configured quite right in my project.  What could it be?

   

Also, why is there a question mark under Desired for Sysclk?

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