Question 2:

when button SW2 is pressed, the onboard RED LED will be blinking at 4Hz frequency

Here is my code for FRDM 64K MCUExpresso

#include

#include "board.h"

#include "peripherals.h"

#include "pin_mux.h"

#include "clock_config.h"

#include "MK64F12.h"

#include "fsl_debug_console.h"

void PIT_CHANNEL_0_IRQHANDLER(void)

{

PIT_ClearStatusFlags(PIT, PIT_CHANNEL_0, kPIT_TimerFlag);

LED_RED_TOGGLE();

LED_GREEN_TOGGLE();

GPIO_PinWrite(GPIOC, 16U, 0U);

}

void SW2_GPIOC_IRQHANDLER(void)

{

GPIO_PinWrite(GPIOC, 16U, 1U);

PRINTF("System status: Armed ");

GPIO_PortClearInterruptFlags(GPIOC, 1U << 6U);

LED_RED_ON();

LED_GREEN_OFF();

}

void SW3_GPIOA_IRQHANDLER(void)

{

GPIO_PinWrite(GPIOC, 16U, 0U);

PRINTF("System status: Disarmed ");

GPIO_PortClearInterruptFlags(GPIOA, 1U << 4U);

LED_RED_OFF();

LED_GREEN_ON();

}

int main(void)

{

BOARD_InitBootPins();

BOARD_InitBootClocks();

BOARD_InitBootPeripherals();

#ifndef BOARD_INIT_DEBUG_CONSOLE_PERIPHERAL

BOARD_InitDebugConsole();

#endif

LED_RED_OFF();

LED_GREEN_ON();

PRINTF("Press SW2 to Arm System ");

PRINTF("Press SW3 to Disarm System ");

PRINTF("System status: Disarmed ");

volatile static int i = 0 ;

while(1) {

i++ ;

__asm volatile ("nop");

}

return 0 ;

}