kw38点灯大师2_GPIO中断

frdmkw38_gpio_led_output 工程 frdmkw38_gpio_input_interrupt 工程

主函数

int main(void)
{
    /* Define the init structure for the output LED pin*/
    gpio_pin_config_t led_config = {
        kGPIO_DigitalOutput,
        0,
    };

    /* Define the init structure for the input switch pin */
    gpio_pin_config_t sw_config = {
        kGPIO_DigitalInput,
        0,
    };

    /* Board pin, clock, debug console init */
    BOARD_InitPins();
    BOARD_BootClockRUN();
    BOARD_InitDebugConsole();

    /* Print a note to terminal. */
    PRINTF("\r\n GPIO Driver example\r\n");
    PRINTF("\r\n The LED is blinking.\r\n");
    PRINTF("\r\n 按压开关 %s 来开关和切换LED.\r\n", BOARD_SW_NAME);

/* Init input switch GPIO. */
#if (defined(FSL_FEATURE_PORT_HAS_NO_INTERRUPT) && FSL_FEATURE_PORT_HAS_NO_INTERRUPT)
    GPIO_SetPinInterruptConfig(BOARD_SW2_GPIO, BOARD_SW2_GPIO_PIN, kGPIO_InterruptFallingEdge);
#else
    PORT_SetPinInterruptConfig(BOARD_SW2_PORT, BOARD_SW2_GPIO_PIN, kPORT_InterruptFallingEdge);
#endif
    EnableIRQ(BOARD_SW2_IRQ);
    GPIO_PinInit(BOARD_SW2_GPIO, BOARD_SW2_GPIO_PIN, &sw_config);

    /* Init output LED GPIO. */
    GPIO_PinInit(BOARD_LED_GPIO0, BOARD_LED_GPIO_PIN0, &led_config);
    GPIO_PinInit(BOARD_LED_GPIO1, BOARD_LED_GPIO_PIN1, &led_config);
    GPIO_PinInit(BOARD_LED_GPIO2, BOARD_LED_GPIO_PIN2, &led_config);

    uint32_t temp = 0;
    while (1)
    {
        if (g_ButtonPress)
        {
            temp ++;
            PRINTF(" %s is pressed, it is time: %d \r\n", BOARD_SW_NAME, temp);
            switch(temp%3)
            {
            case 0:
                PRINTF(" case 0, BLUE LED ON");
                LED_RED_OFF();
                LED_GREEN_OFF();
                LED_BLUE_ON();
                break;
            case 1:
                PRINTF(" case 1, GREEN LED ON");
                LED_RED_OFF();
                LED_GREEN_ON();
                LED_BLUE_OFF();
                break;
            case 2:
                PRINTF(" case 2, RED LED ON");
                LED_RED_ON();
                LED_GREEN_OFF();
                LED_BLUE_OFF();
                break;
            }
//            /* Toggle LED. */
//            GPIO_PortToggle(BOARD_LED_GPIO, 1U << BOARD_LED_GPIO_PIN);
//            /* Reset state of button. */
            g_ButtonPress = false;
        }
    }
}

中断处理函数

void BOARD_SW2_IRQ_HANDLER()
{
    /* Clear external interrupt flag. */
    GPIO_PortClearInterruptFlags(BOARD_SW2_GPIO, 1U << BOARD_SW2_GPIO_PIN);
    /* Change state of button. */
    g_ButtonPress = true;
/* Add for ARM errata 838869, affects Cortex-M4, Cortex-M4F Store immediate overlapping
  exception return operation might vector to incorrect interrupt */
#if defined __CORTEX_M && (__CORTEX_M == 4U)
    __DSB();
#endif
}

预定义

#define BOARD_LED_GPIO0 BOARD_LED_RED_GPIO
#define BOARD_LED_GPIO_PIN0 BOARD_LED_RED_GPIO_PIN

#define BOARD_LED_GPIO1 BOARD_LED_GREEN_GPIO
#define BOARD_LED_GPIO_PIN1 BOARD_LED_GREEN_GPIO_PIN

#define BOARD_LED_GPIO2 BOARD_LED_BLUE_GPIO
#define BOARD_LED_GPIO_PIN2 BOARD_LED_BLUE_GPIO_PIN

#define BOARD_SW_NAME BOARD_SW2_NAME

总结GPIO中断的流程

1. 变量flag volatile bool g_ButtonPress = false; 指示是否按下开关
2. 中断处理函数 void BOARD_SW2_IRQ_HANDLER()
   1. 先清空外部中断，GPIO_PortClearInterruptFlags(BOARD_SW2_GPIO, 1U << BOARD_SW2_GPIO_PIN);
   2. 再对flag置一，表示中断已经发生；
   3. 之后，它会进入到main的while循环里面的if(g_ButtonPress);
3. main函数里面初始化板子之后，要初始化SW的GPIO；
   1. 中断config设置 GPIO_SetPinInterruptConfig(BOARD_SW2_GPIO, BOARD_SW2_GPIO_PIN, kGPIO_InterruptFallingEdge);;
   2. GPIO_PinInit GPIO_PinInit(BOARD_SW2_GPIO, BOARD_SW2_GPIO_PIN, &sw_config);
4. 然后 EnableIRQ(BOARD_SW2_IRQ);