ESPTerm is a terminal emulator running on the ESP8266 WiFi chip.
The firmware emulates VT102 with some additional features based on `xterm` and later VT models, and the terminal screen can be accessed using any web browser, even on a phone or tablet. It works with ESP-01, ESP-01S and ESP-12 and likely many other modules.
This project is based on SpriteTM's esphttpd and libesphttpd, forked by MightyPork to
[MightyPork/esphttpd](https://github.com/MightyPork/esphttpd) and
ESPTerm can be used to add remote access via WiFi to any embeded project, all you need is a serial port.
Those forks include improvements not available upstream.
## Screenshots, photos
## Goals
- Look at the [GitHub releases page][releases], there are some pics.
The project aims to be a wireless terminal emulator that'll work with the likes of
Arduino, AVR, PIC, STM8, STM32, mbed etc, anything with UART, even your USB-serial dongle will work.
## ESPTerm features
Connect it to the master device via UART and use the terminal on the built-in web page for debug logging,
remote control etc. It works like a simple LCD screen, in a way.
- **Robust WiFi configuration interface**
- static IP
- DHCP
- AP channel and strength setting
- AP password
- SSID search for finding your existing network
- **Almost complete VT102 emulation** with some extras
- *Sufficient to run most Linux console applications, including ncurses-based ones\**
- All standard SGR (text style attributes) supported
- Full UTF-8 support
- Alternate character sets support
- 16 colors
- Scrolling Region, Origin Mode
- Tab Stops
- Cursor save/restore
- Character/Line insert, delete, clear operations
- Audible BEL (ASCII 7 beep)
- Most standard queries (get cursor position, get SGR, get screen size...)
- All DEC private options either implemented or safely consumed by the parser
- **Other features:**
- Screen size up to 80x25
- Real-time screen update via WebSocket
- Button to open Android software keyboard
- 5 buttons under the screen for quick commands
- Button labels can be changed (by OSC commands or via settings)
- Screen title can be changed (by OSC commands or via settings)
- Built-in help page with basic troubleshooting and command reference
It lets you make simple UI (manipulating the screen with ANSI sequences) and receive input from buttons on
the webpage (and keyboard on PC). There is some rudimentary touch input as well.
\*) Linux console applications run via agetty at ttyUSB0 were used for testing, obviously you'll be better off using SSH for remote shell
The screen size is adjustable up to 25x80 (via a special control sequence) and uses 16 standard colors
(8 dark and 8 bright). Both default size and colors can be configured in the settings.
ESPTerm firmware is written in C and is based on SpriteTM's `libesphttpd` http server library, forked by MightyPork to
[MightyPork/libesphttpd](https://github.com/MightyPork/libesphttpd) respectively. This fork includes various improvements and changes required by the project.
## Project status
## Running ESPTerm
*A little buggy, but mostly okay! There are many features and fixes planned, but it should be fairly usable already.*
To run ESPTerm on your ESP8266, either build it yourself from source using `xtensa-lx106-elf-gcc` (and the included Makefile), or download pre-built binaries from the [GitHub releases section][releases]. Flash the binaries using [esptool](https://github.com/espressif/esptool).
- We have a working **2-way terminal** (UART->ESP->Browser and vice versa) with real-time update via websocket.
This means that what you type in the browser is sent to UART0 and what's received on UART0 is processed by the
ANSI parser and applied to the internal screen buffer. You'll also immediately see the changes in your browser.
There's a filter in the way that discards garbage characters (like unicode and most ASCII outside 32-126).
For a quick test, try connecting the UART0 Rx and Tx with a piece of wire to make a loopback interface.
*NOTE: Use the bare module, not something like LoLin or NodeMCU with a FTDI, it'll interfere*.
You should then directly see what you type & can even try some ANSI sequences, right from the browser.
- All ANSI sequences that make sense, as well as control codes like Backspace and CR / LF are implemented.
Set colors with your usual `\e[31;1m` etc (see Wikipedia). `\e` is the ASCII code 27 (ESC).
Arrow keys generate ANSI sequences, ESC sends literal ASCII code 27 etc. Almost everything can be input
straight from the browser.
### Pins
- Buttons pressed in the browser UI send ASCII codes 1..5. Mouse clicks are sent as `\e[<row>;<col>M`.
- Pin GPIO2 is used for debug messages at 115200 baud, 8 bit, no parity.
- Pins Rx and Tx are used for the main communication UART. Connect your USB-serial dongle or application microcontroller here.
- There's a built-in WiFi config page and a Help page with a list of all supported ANSI sequences and other details.
### Console commands - escape sequences
- A list of most supported commands can be found here: http://bits.ondrovo.com/espterm-xterm.html
- To set the screen title, use `OSC 0 ; title ST` (`OSC` = `ESC ]`, `ST` = `ESC \` or ASCII 7)
- To set buttons text, use `OSC 8 1 ; text ST` with 81 through 85.
- Mouse clicks (as of v0.6.9) generate `CSI row ; col M` at the Tx pin (`CSI` = `ESC [`)
- For more info, look eg. on Wikipedia or here: http://ascii-table.com/ansi-escape-sequences-vt-100.php
### Setup
- When flashed for the first time, ESPTerm wipes any possible previous WiFi configuration, because it implements its own WiFi config manager with many additional features.
- It should start in AP mode, the default SSID being `TERM-MACADR` with `MACADR` being three unique bytes from the MAC address / Device ID.
- Connect to it via a smartphone or laptop and configure WiFi as desired.
- To re-enable the built-in AP, hold the BOOT (GPIO0) button for about 1 s, until the blue LED starts slowly flashing. Then release the button!
- To reset all settings to defaults, hold the BOOT (GPIO0) button until the blue LED flashes rapidly, then release the button.
- When you accidentally make the blue LED flash, you can cancel the operation by pressing Reset or disconnecting its power supply. The wipe is done on the button's release.
### Config files
ESPTerm has two config "files", one for defaults and one for the currently used settings. In the case of the terminal config, there is also a third, temporary file for changes done via ESC commands.
When you get your settings *just right*, you can store them as defaults, which can then be at any time restored by holding the BOOT (GPIO0) button. You can do this on the System Settings page. This asks for an "admin password", which you can define when building the firmware in the `esphttpdconfig.mk` file. The default password is `19738426`. This password can't presently be changed without re-flashing the firmware.
You can also restore everything (except the saved defaults) to "factory defaults", there is a button for this on the System Settings page. Those are the initial values in the config files.
## Development
### Installation for development
- Clone this project with `--recursive`, or afterwards run `git submodule init` and `git submodule update`.
- Install [esp-open-sdk](https://github.com/pfalcon/esp-open-sdk/) and build it with
`make toolchain esptool libhal STANDALONE=n`.
`make toolchain esptool libhal STANDALONE=n`.
Make sure the `xtensa-lx106-elf/bin` folder is on $PATH.
- Install [esptool](https://github.com/espressif/esptool) (it's in the Arch community repo and on AUR, too)
- Set up udev rules so you have access to ttyUSB0 without root, eg:
