InterruptIn - ピン変化割込み

p5へ接続されたスイッチからの割り込みでLEDを点滅させる

#include "mbed.h"

InterruptIn button(p5);
DigitalOut led(LED1);
DigitalOut flash(LED4);

void flip() {
    led = !led;
}

int main() {
    button.rise(&flip);  // attach the address of the flip function to the rising edge
    while(1) {           // wait around, interrupts will interrupt this!
        flash = !flash;
        wait(0.25);
    }
}

P5(P0.9)立下りでLED(P1.18)点滅

#include "LPC17xx.h"

#ifdef __cplusplus 
extern "C" { 
  void EINT3_IRQHandler ();
} 
#endif

void EINT3_IRQHandler () {
    static volatile int n = 0;

    n ++;
    if (n & 1) {
        LPC_GPIO0->FIOSET = (1 << 22); // high
    } else {
        LPC_GPIO0->FIOCLR = (1 << 22); // low
    }
    LPC_GPIOINT->IO0IntClr |= (1 << 9);  // clear flag
}

int main(void) {

    LPC_PINCON->PINSEL1  &= ~(3 << 12); // GPIO (00)
    LPC_GPIO0->FIODIR |= (1 << 22);  // output

    LPC_PINCON->PINSEL0  &= ~(3 << 18); // GPIO (00)
    LPC_PINCON->PINMODE0 &= ~(2 << 18); // pull-up (00)
    LPC_GPIO0->FIODIR &= ~(1 << 9); // input

    NVIC_EnableIRQ(EINT3_IRQn);
    LPC_GPIOINT->IO0IntEnF |= (1 << 9);  // fall interrupt
    __enable_irq();
    
    while(1);
}

              SW
              ___
          +---o o---[100ohm]---+--- InterruptIn (mode=PullUp)
          |                    |
    GND---+--------||----------+
                 0.01uF