提要：針對於Ubuntu下的ESP32搭建，網上有很多博文，樂鑫官網也有指導手冊，對於到家都知道的部分我就一帶而過，我主要描述搭建過程中遇到的問題和細節。
1.創建一個ESP的目錄
I)切換到root用戶
II)在root目錄下創建個esp文件夾
mkdir ~/esp
III)切換到ESP目錄下
cd ~/esp
2.工具鏈設置
I)先下載python支持庫
sudo apt-get install git wget make libncurses-dev flex bison gperf python python-serial
II)下載工具鏈
for 64-bit Linux:
https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-1.22.0-75-gbaf03c2-5.2.0.tar.gz
for 32-bit Linux:
https://dl.espressif.com/dl/xtensa-esp32-elf-linux32-1.22.0-75-gbaf03c2-5.2.0.tar.gz
我的用的是64bitLinux，下載以后的文件是這樣的
III)將工具鏈解壓到esp文件目錄下
tar -xzf ~/Downloads/xtensa-esp32-elf-linux64-1.22.0-75-gbaf03c2-5.2.0.tar.gz ~/esp
IV)將esp工具鏈寫入環境變量PATH中。
在~/.bashrc文件中寫入：
export PATH="$PATH:$HOME/esp/xtensa-esp32-elf/bin"
V)重新讀取PATH環境變量
source ~/.bashrc
printenv PATH
若是可以看到esp工具鏈的目錄，則表示工具鏈設置成功了！
3.下載ESP-IDF（也就是樂鑫提供的SDK）
I)下載SDK
git clone --recursive https://github.com/espressif/esp-idf.git
II)添加IDF_PATH環境變量
在 ~/.bashrc文件添加：
export IDF_PATH=~/esp/esp-idf
加載~/.bashrc文件：
Source ~/.bashrc
檢查IDF_PATH
printenv IDF_PATH
如果打印出IDF_PATH的目錄的話，則表示添加成功
4）開始一個工程
I)在SDK中拷貝一個Demo到esp文件夾下
cp -r $IDF_PATH/examples/get-started/hello_world .
II)設置參數
執行 make menuconfig，會出現以下界面：（置於具體參數的含義，請自行了解）
III)編譯與運行
在確保硬件連接無誤的情況下，執行 make flash，程序將要編譯，若編譯沒有錯誤，將直接下載到Flash中，出現以下界面，表示程序已經正常運行。
note:提供一些make 指令集，可供開發使用
Welcome to Espressif IDF build system. Some useful make targets:
make menuconfig - Configure IDF project
make defconfig - Set defaults for all new configuration options
make all - Build app, bootloader, partition table
make flash - Flash app, bootloader, partition table to a chip
make clean - Remove all build output
make size - Display the static memory footprint of the app
make size-components, size-files - Finer-grained memory footprints
make erase_flash - Erase entire flash contents
make monitor - Run idf_monitor tool to monitor serial output from app
make simple_monitor - Monitor serial output on terminal console
make list-components - List all components in the project
make app - Build just the app
make app-flash - Flash just the app
make app-clean - Clean just the app
make print_flash_cmd - Print the arguments for esptool when flash
See also 'make bootloader', 'make bootloader-flash', 'make bootloader-clean',
'make partition_table', etc, etc.ls
* 5)更新ESP-IDF（這階段本人並未實踐，以下內容來自樂鑫官網）
After some time of using ESP-IDF, you may want to update it to take advantage of new features or bug fixes. The simplest way to do so is by deleting existing esp-idffolder and cloning it again, exactly as when doing initial installation described in sections Get ESP-IDF.
Another solution is to update only what has changed. This method is useful if you have slow connection to the GiHub. To do the update run the following commands:
cd ~/esp/esp-idf
git pull
git submodule update --init --recursive
The git pull command is fetching and merging changes from ESP-IDF repository on GitHub. Then git submodule update --init --recursive is updating existing submodules or getting a fresh copy of new ones. On GitHub the submodules are represented as links to other repositories and require this additional command to get them onto your PC.
If you would like to use specific release of ESP-IDF, e.g. v2.1, run:
cd ~/esp
git clone https://github.com/espressif/esp-idf.git esp-idf-v2.1
cd esp-idf-v2.1/
git checkout v2.1
git submodule update --init --recursive
After that remember to Add IDF_PATH to User Profile, so the toolchain scripts know where to find the ESP-IDF in it’s release specific location.