| Supported Targets | ESP32 | ESP32-C3 | ESP32-S2 | ESP32-S3 | | ----------------- | ----- | -------- | -------- | -------- | # Console Example (See the README.md file in the upper level 'examples' directory for more information about examples.) This example illustrates the usage of the [Console Component](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/console.html#console) to create an interactive shell on the ESP32. The interactive shell running on the ESP32 can then be controlled/interacted with over a serial port (UART). The interactive shell implemented in this example contains a wide variety of commands, and can act as a basis for applications that require a command-line interface (CLI). ## How to use example ### Hardware Required This example should be able to run on any commonly available ESP32 development board. ### Configure the project ``` idf.py menuconfig ``` * Enable/disable `Example Configuration > Store command history in flash` as necessary ### Build and Flash Build the project and flash it to the board, then run monitor tool to view serial output: ``` idf.py -p PORT flash monitor ``` (Replace PORT with the name of the serial port to use.) (To exit the serial monitor, type ``Ctrl-]``.) See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects. ## Example Output Enter the `help` command get a full list of all available commands. The following is a sample session of the Console Example where a variety of commands provided by the Console Example are used. Note that GPIO15 is connected to GND to remove the boot log output. ``` This is an example of ESP-IDF console component. Type 'help' to get the list of commands. Use UP/DOWN arrows to navigate through command history. Press TAB when typing command name to auto-complete. [esp32]> help help Print the list of registered commands free Get the total size of heap memory available restart Restart the program deep_sleep [-t <t>] [--io=<n>] [--io_level=<0|1>] Enter deep sleep mode. Two wakeup modes are supported: timer and GPIO. If no wakeup option is specified, will sleep indefinitely. -t, --time=<t> Wake up time, ms --io=<n> If specified, wakeup using GPIO with given number --io_level=<0|1> GPIO level to trigger wakeup join [--timeout=<t>] <ssid> [<pass>] Join WiFi AP as a station --timeout=<t> Connection timeout, ms <ssid> SSID of AP <pass> PSK of AP [esp32]> free 257200 [esp32]> deep_sleep -t 1000 I (146929) deep_sleep: Enabling timer wakeup, timeout=1000000us I (619) heap_init: Initializing. RAM available for dynamic allocation: I (620) heap_init: At 3FFAE2A0 len 00001D60 (7 KiB): DRAM I (626) heap_init: At 3FFB7EA0 len 00028160 (160 KiB): DRAM I (645) heap_init: At 3FFE0440 len 00003BC0 (14 KiB): D/IRAM I (664) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM I (684) heap_init: At 40093EA8 len 0000C158 (48 KiB): IRAM This is an example of ESP-IDF console component. Type 'help' to get the list of commands. Use UP/DOWN arrows to navigate through command history. Press TAB when typing command name to auto-complete. [esp32]> join --timeout 10000 test_ap test_password I (182639) connect: Connecting to 'test_ap' I (184619) connect: Connected [esp32]> free 212328 [esp32]> restart I (205639) restart: Restarting I (616) heap_init: Initializing. RAM available for dynamic allocation: I (617) heap_init: At 3FFAE2A0 len 00001D60 (7 KiB): DRAM I (623) heap_init: At 3FFB7EA0 len 00028160 (160 KiB): DRAM I (642) heap_init: At 3FFE0440 len 00003BC0 (14 KiB): D/IRAM I (661) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM I (681) heap_init: At 40093EA8 len 0000C158 (48 KiB): IRAM This is an example of ESP-IDF console component. Type 'help' to get the list of commands. Use UP/DOWN arrows to navigate through command history. Press TAB when typing command name to auto-complete. [esp32]> ``` ## Troubleshooting ### Line Endings The line endings in the Console Example are configured to match particular serial monitors. Therefore, if the following log output appears, consider using a different serial monitor (e.g. Putty for Windows) or modify the example's [UART configuration](#Configuring-UART-and-VFS). ``` This is an example of ESP-IDF console component. Type 'help' to get the list of commands. Use UP/DOWN arrows to navigate through command history. Press TAB when typing command name to auto-complete. Your terminal application does not support escape sequences. Line editing and history features are disabled. On Windows, try using Putty instead. esp32> ``` ## Example Breakdown ### Configuring UART The ``initialize_console()`` function in the example configures some aspects of UART relevant to the operation of the console. - **Line Endings**: The default line endings are configured to match those expected/generated by common serial monitor programs, such as `screen`, `minicom`, and the `idf_monitor.py` included in the SDK. The default behavior for these commands are: - When 'enter' key is pressed on the keyboard, `CR` (0x13) code is sent to the serial device. - To move the cursor to the beginning of the next line, serial device needs to send `CR LF` (0x13 0x10) sequence. ### Line editing The main source file of the example illustrates how to use `linenoise` library, including line completion, hints, and history. ### Commands Several commands are registered using `esp_console_cmd_register()` function. See the `register_wifi()` and `register_system()` functions in `cmd_wifi.c` and `cmd_system.c` files. ### Command handling Main loop inside `app_main()` function illustrates how to use `linenoise` and `esp_console_run()` to implement read/eval loop. ### Argument parsing Several commands implemented in `cmd_wifi.c` and `cmd_system.c` use the Argtable3 library to parse and check the arguments. ### Command history Each time a new command line is obtained from `linenoise`, it is written into history and the history is saved into a file in flash memory. On reset, history is initialized from that file.