/*
 * MSP432 GPIO - Pin 6.7 with Timer32_0
 *
 */

#include <stdint.h>  //Exact-width integer types
#include <ti\devices\msp432p4xx\driverlib\driverlib.h>  //Driver library


#define DCO_FREQ    48e6  //unit: Hz; DCO nominal frequencies: 1.5, 3, 6, 12, 24, 48 MHz.
#define TIMER0_FREQ   500000  //unit: Hz


//function prototypes
void initDevice(void);
void initTimer(void);
void initGPIO(void);


//global variables
uint32_t clockMCLK;


void main(void)
{
    initDevice();
    initTimer();
    initGPIO();


    //Enable interrupts
    Interrupt_enableSleepOnIsrExit();
    Interrupt_enableMaster();

    Timer32_startTimer(TIMER32_0_BASE, false);

    while(1)
    {
        PCM_gotoLPM0();
    }

}


void initDevice(void)
{
    WDT_A_holdTimer();  //stop Watchdog timer

    //Change VCORE to 1 to support a frequency higher than 24MHz.
    //See data sheet for Flash wait-state requirement for a given frequency.
    PCM_setPowerState(PCM_AM_LDO_VCORE1);
    FlashCtl_setWaitState(FLASH_BANK0, 1);
    FlashCtl_setWaitState(FLASH_BANK1, 1);

    //Enable FPU for DCO Frequency calculation.
    FPU_enableModule();
    FPU_enableLazyStacking(); // Required to use FPU within ISR.

    //Only use DCO nominal frequencies: 1.5, 3, 6, 12, 24, 48MHz.
    CS_setDCOFrequency(DCO_FREQ);

    //Divider: 1, 2, 4, 8, 16, 32, 64, or 128.
    //SMCLK used by UART and ADC14.
    CS_initClockSignal(CS_MCLK, CS_DCOCLK_SELECT, CS_CLOCK_DIVIDER_1);
    CS_initClockSignal(CS_HSMCLK, CS_DCOCLK_SELECT, CS_CLOCK_DIVIDER_8);
    CS_initClockSignal(CS_SMCLK, CS_DCOCLK_SELECT, CS_CLOCK_DIVIDER_16);

    clockMCLK = CS_getMCLK();
}


void initTimer(void)
{
    Timer32_initModule(TIMER32_0_BASE, TIMER32_PRESCALER_1, TIMER32_32BIT, TIMER32_PERIODIC_MODE);
    Timer32_setCount(TIMER32_0_BASE, clockMCLK/TIMER0_FREQ - 1);
    Timer32_enableInterrupt(TIMER32_0_BASE);
    Interrupt_enableInterrupt(INT_T32_INT1); //Enable Timer32_0 interrupt in the interrupt controller.
}


void initGPIO(void)
{
    //Configure P6.7 as output.
    GPIO_setAsOutputPin(GPIO_PORT_P6, GPIO_PIN7);
}


//Timer32_0 ISR
void T32_INT1_IRQHandler(void)
{
    Timer32_clearInterruptFlag(TIMER32_0_BASE);
    GPIO_toggleOutputOnPin(GPIO_PORT_P6, GPIO_PIN7);
}