esp-open-rtos/examples/button/button.c

/* Respond to a button press.
 *
 * This code combines two ways of checking for a button press -
 * busy polling (the bad way) and button interrupt (the good way).
 *
 * This sample code is in the public domain.
 */
#include "espressif/esp_common.h"
#include "esp/uart.h"
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "esp8266.h"

/* pin config */
const int gpio = 0;   /* gpio 0 usually has "PROGRAM" button attached */
const int active = 0; /* active == 0 for active low */
const gpio_inttype_t int_type = GPIO_INTTYPE_EDGE_NEG;
#define GPIO_HANDLER gpio00_interrupt_handler


/* This task polls for the button and prints the tick
   count when it's seen.

   Debounced to 200ms with a simple vTaskDelay.

   This is not a good example of how to wait for button input!
*/
void buttonPollTask(void *pvParameters)
{
    printf("Polling for button press on gpio %d...\r\n", gpio);
    while(1) {
        while(gpio_read(gpio) != active)
        {
            taskYIELD();
        }
        printf("Polled for button press at %dms\r\n", xTaskGetTickCount()*portTICK_RATE_MS);
        vTaskDelay(200 / portTICK_RATE_MS);
    }
}

/* This task configures the GPIO interrupt and uses it to tell
   when the button is pressed.

   The interrupt handler communicates the exact button press time to
   the task via a queue.

   This is a better example of how to wait for button input!
*/
void buttonIntTask(void *pvParameters)
{
    printf("Waiting for button press interrupt on gpio %d...\r\n", gpio);
    xQueueHandle *tsqueue = (xQueueHandle *)pvParameters;
    gpio_set_interrupt(gpio, int_type);

    uint32_t last = 0;
    while(1) {
        uint32_t button_ts;
        xQueueReceive(*tsqueue, &button_ts, portMAX_DELAY);
        button_ts *= portTICK_RATE_MS;
        if(last < button_ts-200) {
            printf("Button interrupt fired at %dms\r\n", button_ts);
            last = button_ts;
        }
    }
}

static xQueueHandle tsqueue;

void GPIO_HANDLER(void)
{
    uint32_t now = xTaskGetTickCountFromISR();
    xQueueSendToBackFromISR(tsqueue, &now, NULL);
}

void user_init(void)
{
    uart_set_baud(0, 115200);
    gpio_enable(gpio, GPIO_INPUT);

    tsqueue = xQueueCreate(2, sizeof(uint32_t));
    xTaskCreate(buttonIntTask, (signed char *)"buttonIntTask", 256, &tsqueue, 2, NULL);
    xTaskCreate(buttonPollTask, (signed char*)"buttonPollTask", 256, NULL, 1, NULL);
}