MSP432P401R: UART_write() execution during interrupt callback function stopping execution of code

Part Number: MSP432P401R
Other Parts Discussed in Thread: SYSCONFIG

Hi, below is a snippet of the basic code I'm running.

void gpioButtonFxn0(uint_least8_t index)
{
    /* Clear the GPIO interrupt and toggle an LED */
    GPIO_toggle(Board_GPIO_LED0);

    res = ADC_convert(adc, &adcValue0);
    adcValue0MicroVolt = ADC_convertRawToMicroVolts(adc, adcValue0);
    printf("%d\n", adcValue0MicroVolt);

    UART_write(uart, &adcValue0MicroVolt, sizeof(adcValue0MicroVolt));
    printf("UART_write() finished\n");
}

/*
 *  ======== mainThread ========
 */
void *mainThread(void *arg0)
{
    /* Call driver init functions */
    GPIO_init();
    ADC_init();
    UART_init();
    // I2C_init();
    // SPI_init();
    // Watchdog_init();

    // initialiaze ADC
    ADC_Params_init(&params);
    adc = ADC_open(Board_ADC0, &params);

    if (adc == NULL) {
        printf("ADC_open() failed\n");
        while (1);
    }

    // initialize UART
    UART_Params_init(&uartParams);
    uartParams.writeMode = UART_MODE_CALLBACK;
    uartParams.writeDataMode = UART_DATA_BINARY;
    uartParams.readDataMode = UART_DATA_BINARY;
    uartParams.readReturnMode = UART_RETURN_FULL;
    uartParams.readEcho = UART_ECHO_OFF;
    uartParams.baudRate = 115200;

    uart = UART_open(Board_UART0, &uartParams);

    if (uart == NULL) {
        printf("UART_open() failed\n");
        while (1);
    }

    /* Turn on user LED */
    GPIO_write(Board_GPIO_LED0, Board_GPIO_LED_ON);

    /* Enable interrupts */
    GPIO_enableInt(Board_GPIO_6_1);

    while (1) {
        sleep(1);
        printf("In while loop...\n");
    }
}

If I comment out the UART_write() line in my callback function, I'm able to continuously toggle my LED and perform ADC conversions (at the same time, "In while loop..." keeps printing). However, with the UART_write() command, the execution of this code completely stops. I reach the printing "UART_write() finished" portion, but my code no longer executes. Does anyone know why this may be?

Regards,

Michael