RTOS/MSP-EXP430F5529LP: GPIO interrupt setup for P2_0

Tool/software: TI-RTOS

I wish to configure a GPIO pin to give an interrupt on a low going square Wave signal from DS3231 RTC chip.

I have started with the gpiointerrupt example and made the following changes. The intention was to use TI-RTOS to setup 1 callback per port interrupt and then use the index value to switch to the appropriate pin action. I added a GPIO pin setting to gpioPinConfigs in MSP_EXP430F5529LP.c and a  GPIO name for the extra pin in MSP_EXP430F5529LP.h.

/*
 *  ======== MSP_EXP430F5529LP.c ========
 *  This file is responsible for setting up the board specific items for the
 *  MSP_EXP430F5529LP board.
 */
GPIO_PinConfig gpioPinConfigs[] = {
    /* Input pins */
    /* MSP_EXP430F5529LP_RTC P2_0 Input with Falling Edge Interrupt*/
    GPIOMSP430_P2_0 | GPIO_CFG_IN_PU | GPIO_CFG_IN_INT_FALLING,
    /* MSP_EXP430F5529LP_S1 */
    GPIOMSP430_P2_1 | GPIO_CFG_IN_PU | GPIO_CFG_IN_INT_RISING,
    /* MSP_EXP430F5529LP_S2 */
    GPIOMSP430_P1_1 | GPIO_CFG_IN_PU | GPIO_CFG_IN_INT_RISING,

    /* Output pins */
    /* MSP_EXP430F5529LP_LED1 */
    GPIOMSP430_P1_0 | GPIO_CFG_OUT_STD | GPIO_CFG_OUT_STR_HIGH | GPIO_CFG_OUT_LOW,
    /* MSP_EXP430F5529LP_LED2 */
    GPIOMSP430_P4_7 | GPIO_CFG_OUT_STD | GPIO_CFG_OUT_STR_HIGH | GPIO_CFG_OUT_LOW,
};
.
.
.
/** ============================================================================
 *  @file       MSP_EXP430F5529LP.h
 *
 *  @brief      MSP_EXP430F5529LP Board Specific APIs
 *
 *  The MSP_EXP430F5529LP header file should be included in an application as
 *  follows:
 *  @code
 *  #include <MSP_EXP430F5529LP.h>
 *  @endcode
 *
 *  ============================================================================
 */
/*!
 *  @def    MSP_EXP430F5529LP_GPIOName
 *  @brief  Enum of GPIO names on the MSP_EXP430F5529LP dev board
 *  in ame order as PinConfigs[]
 */
typedef enum MSP_EXP430F5529LP_GPIOName {
	MSP_EXP430F5529LP_RTC = 0, /* port 2 pin 0 */
	MSP_EXP430F5529LP_S1 , /* port 2 pin 1 */
    MSP_EXP430F5529LP_S2, /* port 1 pin 1 */

    MSP_EXP430F5529LP_LED1,
    MSP_EXP430F5529LP_LED2,

    MSP_EXP430F5529LP_GPIOCOUNT
} MSP_EXP430F5529LP_GPIOName;

/* main */

/* variable to be read by GUI Composer */
int count1 = 0;
int count2 = 0;
/* variable to be read by GUI Composer */
//int rtccount = 0;




/*
 *  ======== gpioPortFxn2 ========
 *  Callback function for the Port 2
 *  if index is position in gpioPinConfigs[] then we should get 0 or 1
 */
void gpioPortFxn2(unsigned int index)
{
    /* Clear the GPIO interrupt and toggle an LED */
    GPIO_toggle(Board_LED1);

    if (count2++ == 100) {
        count2 = 0;
    }
    System_printf("Port2 Int %d, %d\n", count2 , index);
    System_flush();
}

/*
 *  ======== gpioPortFxn1 ========
 *  Callback function for the GPIO interrupt on Board_BUTTON0.
 *  *  if index is position in gpioPinConfigs[] then we should get 2
 */
void gpioPortFxn1(unsigned int index)
{
    /* Clear the GPIO interrupt and toggle an LED */
    GPIO_toggle(Board_LED0);

    if (count1++ == 100) {
        count1 = 0;
    }
    System_printf("Port1 Int %d, %d\n", count1 , index);
    System_flush();
}
/* */
/*
 *  ======== main ========
 */
int main(void)
{
    /* Call board init functions */
    Board_initGeneral();
    Board_initGPIO();
    Board_initUART();

    /* Turn on user LED */
    GPIO_write(Board_LED0, Board_LED_ON);

    System_printf("Starting the GPIO Interrupt example\nSystem provider is set"
                  " to SysMin. Halt the target to view any SysMin contents in"
                  " ROV.\n");
    /* SysMin will only print to the console when you call flush or exit */
    System_flush();
    //
    /* install callbacks */
    GPIO_setCallback(MSP_EXP430F5529LP_RTC, gpioPortFxn2);
    GPIO_setCallback(Board_BUTTON0, gpioPortFxn1);
    GPIO_setCallback(Board_BUTTON1, gpioPortFxn2);
    /* Enable interrupts */
    GPIO_enableInt(MSP_EXP430F5529LP_RTC);
    GPIO_enableInt(Board_BUTTON0);
    GPIO_enableInt(Board_BUTTON1);


    /* Start BIOS */
    BIOS_start();

    return (0);
}

With this code the original Button actions trigger an interrupt and I get output to the console from the 2 callback functions.

However the additional GPIO interrupt does not respond. I also note that the P2_0 shows 0v so I wonder if I am missing something in the pin setup?

Starting the GPIO Interrupt example
System provider is set to SysMin. Halt the target to view any SysMin contents in ROV.
Port2 Int 1, 2
Port2 Int 2, 2
Port1 Int 1, 1
Port1 Int 2, 1
Port1 Int 3, 1
Port1 Int 4, 1

I realise I am missing something here. I would welcome any suggestions.