UsbTerminal

UsbTerminal is a terminal emulator (sometimes called "monitor"). It uses the phone’s or tablet’s USB port to communicate with external devices. The phone or tablet must support USB-Host Mode a.k.a USB On-The-Go (USB-OTG), and a USB-OTG cable is required.

Features:
● Support CDC-ACM based devices
● Support FTDI based devices
● Support Winchiphead-CH340/CH341 based devices. (This is somewhat experimental. Please send feedback).
● Support two keyboard input modes:
1. Auto - Like on a “real” terminal, there is no dedicated input field. Characters are sent to the serial device immediately as keys are clicked on the keyboard. This is the default mode.
2. Dedicated input field - Keyboard input goes to a dedicated input field and is sent to the device only after a “Send” button is pressed.
● Support sending control character (e.g. Ctrl-C)
● Support controlling of DTR and CTS
● Log sessions to files. These log files can then be analyzed, emailed, etc
● Large scroll-back buffer (configurable scroll-back buffer size)
● Blinking cursor that indicates the current cursor position on the screen
● Status line. Indication of connection state and error messages
● Build-in help. No need to be online to read the help screen
● No root required

Limitations:
● No support of escape-sequences for cursor positioning, text color, etc. This means no VT100 emulation, and that Unix programs like vi, emacs, top, etc are not supported

Supported USB devices:
● As of version 1.4 it is possible to work with devices that are not predefined in the app, provided that they use one of the three supported protocols (CDC/ACM, FT232R, CH340). When using such non-predefined device, click "Connect USB device" on the main menu, and then select which protocol to use
● Arduino. FTDI-based (e.g. original Arduino Uno), CDC-based (e.g. Arduino Uno R3) and CH340-based (e.g. cheap Arduino clones)
● Any device that uses the FTDI FT232R chip
● Note: Prolific devices (e.g. devices based on the PL2303 chip) are currently NOT supported

If you know of other devices that use CDC-ACM that are currently not supported, and you can email me their technical details (Vendor-ID and Product-ID), I will be glad to add support for them.

A note to Arduino users:
One advantage of UsbTerminal is the way it handles DTR. Typically when an Arduino board is connected to a PC, it will reboot every time a terminal emulator application is connected to it. This is because the PC drops the DTR signal low whenever a connection is formed, and Arduino is designed to reset when DTR line is dropped low. UsbTerminal on the other hand, doesn’t automatically set or reset the DTR signal. When you connect a phone or tablet to an Arduino and open UsbTerminal, your Arduino continues whatever it was doing at the time. If you want it to reboot, you can easily control the DTR signal from UsbTerminal with a dedicated button.