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GPIO ​

API ​

GPIO & RTC GPIO - ESP32 - — ESP-IDF 编程指南 v5.2.1 文档 (espressif.com)

ESP32S2开发学习之路--GPIO与中断（三）_gpio isr-CSDN博客

gpio_config_t 结构体 ​

  • pin_bit_mask端口号：GPIO_SEL_X。
  • intr_type中断触发类型：GPIO_INTR_DISABLE关闭中断触发；GPIO_INTR_POSEDGE上升沿；GPIO_INTR_NEGEDGE下降沿；GPIO_INTR_ANYEDGE双边沿；GPIO_INTR_LOW_LEVEL低电平；GPIO_INTR_HIGH_LEVEL高电平。
  • mode模式：GPIO_MODE_DISABLE关闭；GPIO_MODE_INPUT输入；GPIO_MODE_OUTPUT输出；GPIO_MODE_OUTPUT_OD开漏输出；PIO_MODE_INPUT_OUTPUT_OD开漏输入输出；GPIO_MODE_INPUT_OUTPUT输入输出。
  • pull_up_en上拉电阻：GPIO_PULLUP_DISABLE断开；GPIO_PULLUP_ENABLE使能。
  • pull_down_en下拉电阻：GPIO_PULLDOWN_DISABLE断开；GPIO_PULLDOWN_ENABLE使能。

gpio_config配置函数 ​

c
esp_err_t gpio_config(const gpio_config_t *pGPIOConfig)

用于配置GPIO

gpio_install_isr_service单个gpio中断 ​

c
esp_err_t gpio_install_isr_service(int intr_alloc_flags)

Flags used to allocate the interrupt. One or multiple (ORred) ESP_INTR_FLAG_* values. See esp_intr_alloc.h for more info.

开启一个处理单个引脚中断的服务

This function is incompatible with gpio_isr_register() - if that function is used, a single global ISR is registered for all GPIO interrupts. If this function is used, the ISR service provides a global GPIO ISR and individual pin handlers are registered via the gpio_isr_handler_add() function.

gpio_isr_handler_add添加处理函数 ​

c
esp_err_t gpio_isr_handler_add(gpio_num_t gpio_num, gpio_isr_t isr_handler, void *args)

给某一个引脚添加一个中断处理函数

  • gpio_num -- GPIO number
  • isr_handler -- ISR handler function for the corresponding GPIO number.
  • args -- parameter for ISR handler.

gpio_isr_register所有GPIO中断 ​

c
esp_err_t gpio_isr_register(void (*fn)(void*), void *arg, int intr_alloc_flags, gpio_isr_handle_t *handle)
  • gpio_num -- GPIO number
  • isr_handler -- ISR handler function for the corresponding GPIO number.
  • args -- parameter for ISR handler.

This ISR function is called whenever any GPIO interrupt occurs. See the alternative gpio_install_isr_service() and gpio_isr_handler_add() API in order to have the driver support per-GPIO ISRs.

gpio_set_level设置电平 ​

c
esp_err_t gpio_set_level(gpio_num_t gpio_num, uint32_t level)

gpio_get_level获取电平状态 ​

python
int gpio_get_level(gpio_num_t gpio_num)

If the pad is not configured for input (or input and output) the returned value is always 0.

配置的 时候需要是输入输出模式

示例 ​

c

#include <stdio.h>
#include <inttypes.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "driver/gpio.h"

#define GPIO_OUTPUT_PIN_SEL  (1ULL<<GPIO_NUM_0)
static QueueHandle_t gpio_evt_queue = NULL;

//任务函数
static void gpio_task_example(void* arg)
{
    uint32_t io_num;
    for (;;) {
        if (xQueueReceive(gpio_evt_queue, &io_num, portMAX_DELAY)) {
            printf("GPIO[%"PRIu32"] intr, val: %d\n", io_num, gpio_get_level(io_num));
        }
    }
}


// 中断处理函数
static void IRAM_ATTR gpio_isr_handler(void* arg)
{
    uint32_t gpio_num = (uint32_t) arg;
    xQueueSendFromISR(gpio_evt_queue, &gpio_num, NULL);
}

void app_main(void)
{
    //zero-initialize the config structure.
    gpio_config_t io_conf = {
        //disable interrupt
        .intr_type = GPIO_INTR_NEGEDGE,  // 设置中断,下降沿
        //set as input mode
        .mode = GPIO_MODE_INPUT,
        //bit mask of the pins that you want to set
        .pin_bit_mask = GPIO_OUTPUT_PIN_SEL,
        //disable pull-down mode
        .pull_down_en = 0,
        //enable pull-up mode 打开上拉电阻 
        .pull_up_en = 1,
    };
    //configure GPIO with the given settings
    gpio_config(&io_conf);

    //create a queue to handle gpio event from isr 消息队列
    gpio_evt_queue = xQueueCreate(10, sizeof(uint32_t));
    //start gpio task
    xTaskCreate(gpio_task_example, "gpio_task_example", 2048, NULL, 10, NULL);

    //install gpio isr service
    /*
    安装GPIO ISR服务的驱动，开启每个引脚GPIO中断处理程序 。
    这个函数与gpio_isr_register()不兼容。
    如果使用这个函数，ISR服务将提供一个全局GPIO ISR，并且通过gpio_isr_handler_add()函数注册单个的pin处理程序。
    */
    gpio_install_isr_service(0);
    //hook isr handler for specific gpio pin
    gpio_isr_handler_add(GPIO_NUM_0, gpio_isr_handler, (void*) GPIO_INPUT_IO_0);

}