TIMER CODE¶

Component Architecture¶

- driver
    - tim
        - include
            - tim.h
        - tim.c
        - CMakeLists.txt

driver/timer/CMakeLists.txt¶

set(src_dirs
    .
)

set(include_dirs
    include
)

set(requires
    driver
    esp_timer
    led
)

idf_component_register(SRC_DIRS ${src_dirs} INCLUDE_DIRS ${include_dirs} REQUIRES ${requires})

Note

Note that in the drivers, we used gpio from the ESP-IDF builtin driver library, therefore, we need to indicate this dependency in the REQUIRES field of the CMakeLists.txt file. Also, we use the LED to show the effect of the external interrupt, so we need to add led in the REQUIRES field. Apart from that, for timer, we need to add esp_timer in the REQUIRES field.

tim.h¶

/**
 * @file tim.h
 * @author SHUAIWEN CUI (SHUAIWEN001@e.ntu.edu.sg)
 * @brief This file contains the function prototypes for the TIM component.
 * @version 1.0
 * @date 2024-11-18
 *
 * @copyright Copyright (c) 2024
 *
 */

#ifndef __TIM_H__
#define __TIM_H__

/* Dependencies */
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"
#include "esp_tim.h"
#include "led.h"

/* Function Prototypes */

/**
 * @brief       Initialize a high-precision timer (ESP_TIMER)
 * @param       tps: Timer period in microseconds (μs). For example, to execute the timer interrupt once every second,
 *                   set tps = 1s = 1000000μs.
 * @retval      None
 */
void esptim_int_init(uint64_t tps);

/**
 * @brief       Timer callback function
 * @param       arg: No arguments passed
 * @retval      None
 */
void esptim_callback(void *arg);

#endif /*__TIM_H__*/

tim.c¶

/**
 * @file tim.c
 * @author SHUAIWEN CUI (SHUAIWEN001@e.ntu.edu.sg)
 * @brief This file contains the implementation of the TIM component.
 * @version 1.0
 * @date 2024-11-18
 *
 * @copyright Copyright (c) 2024
 *
 */

#include "tim.h"

/**
 * @brief       Initialize a high-precision timer (ESP_TIMER)
 * @param       tps: Timer period in microseconds (μs). For example, to execute the timer interrupt once every second,
 *                   set tps = 1s = 1000000μs.
 * @retval      None
 */
void esptim_int_init(uint64_t tps)
{
    esp_timer_handle_t esp_tim_handle; /* Timer callback function handle */

    /* Define a timer configuration structure */
    esp_timer_create_args_t tim_periodic_arg = {
        .callback = &esptim_callback, /* Set the callback function */
        .arg = NULL,                  /* No arguments passed */
    };

    esp_timer_create(&tim_periodic_arg, &esp_tim_handle); /* Create a timer event */
    esp_timer_start_periodic(esp_tim_handle, tps);        /* Trigger periodically based on the timer period */
}

/**
 * @brief       Timer callback function
 * @param       arg: No arguments passed
 * @retval      None
 */
void esptim_callback(void *arg)
{
    led_toggle();
}

main.c¶

/**
 * @file main.c
 * @author SHUAIWEN CUI (SHUAIWEN001@e.ntu.edu.sg)
 * @brief 
 * @version 1.0
 * @date 2024-11-17
 * 
 * @copyright Copyright (c) 2024
 * 
 */

/* Dependencies */
// Basic
#include "esp_system.h"
#include "esp_chip_info.h"
#include "esp_psram.h"
#include "esp_flash.h"
#include "nvs_flash.h"
#include "esp_log.h"

// RTOS
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"

// BSP
#include "led.h"
#include "exit.h"
#include "tim.h"

/**
 * @brief Entry point of the program
 * @param None
 * @retval None
 */
void app_main(void)
{
    esp_err_t ret;
    uint32_t flash_size;
    esp_chip_info_t chip_info;

    // uint8_t key;

    // Initialize NVS
    ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND)
    {
        ESP_ERROR_CHECK(nvs_flash_erase()); // Erase if needed
        ret = nvs_flash_init();
    }

    // Get FLASH size
    esp_flash_get_size(NULL, &flash_size);
    esp_chip_info(&chip_info);

    // Display CPU core count
    printf("CPU Cores: %d\n", chip_info.cores);

    // Display FLASH size
    printf("Flash size: %ld MB flash\n", flash_size / (1024 * 1024));

    // Display PSRAM size
    printf("PSRAM size: %d bytes\n", esp_psram_get_size());

    // BSP
    led_init();

    // key_init();
    exit_init();
    esptim_int_init(1000000); // 1s enable timer, of which the callback function toggles the LED

    while (1)
    {
        printf("Hello-ESP32\r\n");
        vTaskDelay(1000);
    }

}