/* www.MicroDigitalEd.com
 * p6_5.c Toggling LEDs independently using Timer32 interrupts
 *
 * This program uses Timer32.1 and Timer32.2 to generate interrupts.
 * In the interrupt handlers, the red and green LEDs are toggled.
 * In the infinite loop the blue LED is toggled.
 * All three LEDs are blinked independently. 
 *
 * Tested with Keil 5.20 and MSP432 Device Family Pack V2.2.0
 * on XMS432P401R Rev C.
 */

#include "msp.h"
void delayMs(int n);

int main(void) {
    __disable_irq();

    /* initialize P2.2-P2.0 for tri-color LEDs */
    P2->SEL1 &= ~7;               /* configure P2.2-P2.0 as simple I/O */
    P2->SEL0 &= ~7;
    P2->DIR |= 7;                 /* P2.2-P2.0 set as output */

    /* configure Timer32.1 */
    TIMER32_1->CONTROL = 0xC2;          /* no prescaler, periodic mode, 32-bit timer. */
    TIMER32_1->LOAD = 2300000-1;        /* set the reload value */
    TIMER32_1->CONTROL |= 0x20;         /* enable interrupt */
    NVIC_SetPriority(T32_INT1_IRQn, 3); /* set priority to 3 in NVIC */
    NVIC_EnableIRQ(T32_INT1_IRQn);      /* enable interrupt in NVIC */

    /* configure Timer32.2 */
    TIMER32_2->CONTROL = 0xC2;          /* no prescaler, periodic mode, 32-bit timer. */
    TIMER32_2->LOAD = 1900000-1;        /* set the reload value */
    TIMER32_2->CONTROL |= 0x20;         /* enable interrupt */
    NVIC_SetPriority(T32_INT2_IRQn, 4); /* set priority to 4 in NVIC */
    NVIC_EnableIRQ(T32_INT2_IRQn);      /* enable interrupt in NVIC */

    __enable_irq();                     /* global enable IRQs */

    while (1) {
        P2->OUT ^= 4;             /* blink blue LED */
        delayMs(1000);
    }
}

void T32_INT1_IRQHandler(void) {
    TIMER32_1->INTCLR = 0;        /* clear raw interrupt flag */
    P2->OUT ^= 1;                 /* toggle red LED */
}

void T32_INT2_IRQHandler(void) {
    TIMER32_2->INTCLR = 0;        /* clear raw interrupt flag */
    P2->OUT ^= 2;                 /* toggle green LED */
}

/* delay milliseconds when system clock is at 3 MHz */
void delayMs(int n) {
    int i, j;
    
    for (j = 0; j < n; j++)
        for (i = 750; i > 0; i--);      /* wait 1 ms */
}