commit f2c0393f218ac48383b7b608c7a48455174aa94a
Author: Yilin Sun <imi415@imi.moe>
Date:   Mon Apr 17 22:42:27 2023 +0800

    Initial commit

diff --git a/CMakeLists.txt b/CMakeLists.txt
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+++ b/CMakeLists.txt
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+# The following lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.16)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(ethernet_hello)
diff --git a/README.md b/README.md
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+| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C6 | ESP32-H2 | ESP32-H4 | ESP32-S2 | ESP32-S3 |
+| ----------------- | ----- | -------- | -------- | -------- | -------- | -------- | -------- | -------- |
+
+# Hello World Example
+
+Starts a FreeRTOS task to print "Hello World".
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+## How to use example
+
+Follow detailed instructions provided specifically for this example.
+
+Select the instructions depending on Espressif chip installed on your development board:
+
+- [ESP32 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/stable/get-started/index.html)
+- [ESP32-S2 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/get-started/index.html)
+
+
+## Example folder contents
+
+The project **hello_world** contains one source file in C language [hello_world_main.c](main/main.c). The file is located in folder [main](main).
+
+ESP-IDF projects are built using CMake. The project build configuration is contained in `CMakeLists.txt` files that provide set of directives and instructions describing the project's source files and targets (executable, library, or both).
+
+Below is short explanation of remaining files in the project folder.
+
+```
+├── CMakeLists.txt
+├── pytest_hello_world.py      Python script used for automated testing
+├── main
+│   ├── CMakeLists.txt
+│   └── hello_world_main.c
+└── README.md                  This is the file you are currently reading
+```
+
+For more information on structure and contents of ESP-IDF projects, please refer to Section [Build System](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/build-system.html) of the ESP-IDF Programming Guide.
+
+## Troubleshooting
+
+* Program upload failure
+
+    * Hardware connection is not correct: run `idf.py -p PORT monitor`, and reboot your board to see if there are any output logs.
+    * The baud rate for downloading is too high: lower your baud rate in the `menuconfig` menu, and try again.
+
+## Technical support and feedback
+
+Please use the following feedback channels:
+
+* For technical queries, go to the [esp32.com](https://esp32.com/) forum
+* For a feature request or bug report, create a [GitHub issue](https://github.com/espressif/esp-idf/issues)
+
+We will get back to you as soon as possible.
diff --git a/main/CMakeLists.txt b/main/CMakeLists.txt
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+++ b/main/CMakeLists.txt
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+idf_component_register(SRCS "main.c"
+                    INCLUDE_DIRS "")
diff --git a/main/main.c b/main/main.c
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+++ b/main/main.c
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+/*
+ * SPDX-FileCopyrightText: 2010-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: CC0-1.0
+ */
+
+#include <stdio.h>
+#include <inttypes.h>
+#include "sdkconfig.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_chip_info.h"
+#include "esp_flash.h"
+
+void app_main(void)
+{
+    printf("Hello world!\n");
+
+    /* Print chip information */
+    esp_chip_info_t chip_info;
+    uint32_t flash_size;
+    esp_chip_info(&chip_info);
+    printf("This is %s chip with %d CPU core(s), WiFi%s%s%s, ",
+           CONFIG_IDF_TARGET,
+           chip_info.cores,
+           (chip_info.features & CHIP_FEATURE_BT) ? "/BT" : "",
+           (chip_info.features & CHIP_FEATURE_BLE) ? "/BLE" : "",
+           (chip_info.features & CHIP_FEATURE_IEEE802154) ? ", 802.15.4 (Zigbee/Thread)" : "");
+
+    unsigned major_rev = chip_info.revision / 100;
+    unsigned minor_rev = chip_info.revision % 100;
+    printf("silicon revision v%d.%d, ", major_rev, minor_rev);
+    if(esp_flash_get_size(NULL, &flash_size) != ESP_OK) {
+        printf("Get flash size failed");
+        return;
+    }
+
+    printf("%" PRIu32 "MB %s flash\n", flash_size / (uint32_t)(1024 * 1024),
+           (chip_info.features & CHIP_FEATURE_EMB_FLASH) ? "embedded" : "external");
+
+    printf("Minimum free heap size: %" PRIu32 " bytes\n", esp_get_minimum_free_heap_size());
+
+    for (int i = 10; i >= 0; i--) {
+        printf("Restarting in %d seconds...\n", i);
+        vTaskDelay(1000 / portTICK_PERIOD_MS);
+    }
+    printf("Restarting now.\n");
+    fflush(stdout);
+    esp_restart();
+}
diff --git a/sdkconfig.ci b/sdkconfig.ci
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index 0000000..e69de29