CCS/MSP430FR5959: Problem using 16MHz external square wave on HFXIN

Tool/software: Code Composer Studio

Hello,

I can set up the 16MHz clock using the DCO, however it will not work using a good external square wave signal into HFXIN.

If I use CS_bypassHFXT(), the code gets stuck at that point.

If i use CS_bypassHFXTWithTimeout(10), it comes back successful, but the frequency is at the default 4.8MHz.

Thanks for any insight.

Elwood

-----------------------

int main(void)
{
const bool InternalClock = false;

WDTCTL = WDTPW | WDTHOLD; // Stop WDT

GPIO_setOutputLowOnPin(
GPIO_PORT_P3,
GPIO_PIN4
);

GPIO_setAsPeripheralModuleFunctionOutputPin( //output the MCLK on P3.4
GPIO_PORT_P3,
GPIO_PIN4,
GPIO_TERNARY_MODULE_FUNCTION
);

P1DIR |= 0x01; // Set P1.0 to output direction

PM5CTL0 &= ~LOCKLPM5; // Disable the GPIO power-on default high-impedance mode
// to activate previously configured port settings

//Must set wait state to 1 when using 16MHz
FRAMCtl_configureWaitStateControl(FRAMCTL_ACCESS_TIME_CYCLES_1);

if(InternalClock) //Internal clock
{ CS_setDCOFreq(CS_DCORSEL_1,CS_DCOFSEL_4); //(CS_DCOFSEL_3 = 8MHz, 4 = 16MHz) Set Digitally Controlled Oscillator (internal oscillator)
CS_clockSignalInit(CS_MCLK,CS_DCOCLK_SELECT,CS_CLOCK_DIVIDER_1); //Set MCLK to 16mHz (divide by 1)
CS_clockSignalInit(CS_SMCLK,CS_DCOCLK_SELECT,CS_CLOCK_DIVIDER_1); //Set SMCLK to 16mHz (divide by 1)
}
else //External clock
{
CS_setExternalClockSource(0, 16000000); //Set external LF clock, HF clock freq
if(CS_bypassHFXTWithTimeout(10) == STATUS_SUCCESS) //Bypass the internal oscillator
{ CS_clockSignalInit(CS_MCLK, CS_HFXTCLK_SELECT, CS_CLOCK_DIVIDER_1); //Set MCLK to 16mHz (divide by 1) //use for external clock
CS_clockSignalInit(CS_SMCLK, CS_HFXTCLK_SELECT, CS_CLOCK_DIVIDER_1); //Set SMCLK to 16mHz (divide by 1) //use for external clock
}
else
{ P1OUT = 0x01; //Clock Fail
while(1);
}

}

ClockValueMCLK = CS_getMCLK();
ClockValueSMCLK = CS_getSMCLK();

for(;;) {
volatile unsigned long int i; // volatile to prevent optimization

P1OUT ^= 0x01; // Toggle P1.0 using exclusive-OR

i = 100000; // SW Delay
do i--;
while(i != 0);
}

return 0;
}