环境说明
- ESP32C3F NodeMCU开发板
- ESP-IDF 5.0.1
一、RGB LED硬件原理图
二、点亮LED
1. 新建工程
复制examples\get-started\blink。
2. 硬件配置
我使用的NodeMCU开发板比较老，还用的是外置2MB flash，所以配置最低支持版本为v0.2。
3. 示例配置
配置LED类型为普通GPIO，GPIO编号为3：
4. 编译运行
LED开始闪烁。
三、API说明
GPIO的API头文件在：components\driver\include\driver\gpio.h。
1. 复位GPIO
/**
* @brief Reset an gpio to default state (select gpio function, enable pullup and disable input and output).
*
* @param gpio_num GPIO number.
*
* @note This function also configures the IOMUX for this pin to the GPIO
* function, and disconnects any other peripheral output configured via GPIO
* Matrix.
*
* @return Always return ESP_OK.
*/
esp_err_t gpio_reset_pin(gpio_num_t gpio_num);
2. 设置GPIO方向
/**
* @brief GPIO set direction
*
* Configure GPIO direction,such as output_only,input_only,output_and_input
*
* @param gpio_num Configure GPIO pins number, it should be GPIO number. If you want to set direction of e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);
* @param mode GPIO direction
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG GPIO error
*
*/
esp_err_t gpio_set_direction(gpio_num_t gpio_num, gpio_mode_t mode);
GPIO模式参数可选值如下：
typedef enum {
GPIO_MODE_DISABLE = GPIO_MODE_DEF_DISABLE, /*!< GPIO mode : disable input and output */
GPIO_MODE_INPUT = GPIO_MODE_DEF_INPUT, /*!< GPIO mode : input only */
GPIO_MODE_OUTPUT = GPIO_MODE_DEF_OUTPUT, /*!< GPIO mode : output only mode */
GPIO_MODE_OUTPUT_OD = ((GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD)), /*!< GPIO mode : output only with open-drain mode */
GPIO_MODE_INPUT_OUTPUT_OD = ((GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD)), /*!< GPIO mode : output and input with open-drain mode*/
GPIO_MODE_INPUT_OUTPUT = ((GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT)), /*!< GPIO mode : output and input mode */
} gpio_mode_t;
3. 设置GPIO输出电平
/**
* @brief GPIO set output level
*
* @note This function is allowed to be executed when Cache is disabled within ISR context, by enabling `CONFIG_GPIO_CTRL_FUNC_IN_IRAM`
*
* @param gpio_num GPIO number. If you want to set the output level of e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);
* @param level Output level. 0: low ; 1: high
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG GPIO number error
*
*/
esp_err_t gpio_set_level(gpio_num_t gpio_num, uint32_t level);