If you’re the kind of person who likes to tinker with the lower levels of Android devices, I think you’re going to love this project. XDA Senior Member Kemonine96 came up with a design he calls the Universal Arduino Serial Adapter. As the name implies, it uses an Arduino board to connect to a serial interface on your target device. The project is still in its infancy, but this image of the working electronics shows off the LCD screen, joystick, and pair of buttons that make up the interface.
There are several ways to connect the serial adapter to your devices. Kemonine included a micro USB connector so that you can monitor the serial terminal on an Android device, but that’s not the only way to patch into a system. He also has an RJ-45 connector (Ethernet jack) that allows him to patch in expansion boards like the one in the photo in order to connect a regular serial cable. Once connected and configured, the rig acts as a bridge between the terminal on your computer and the target device. This displays incoming information on your computer’s terminal, and pushes your typed commands back to the device.
A respectable set of features have been built into the design. Possibly the best part is that it is 5V, 3.3V and 1.8V tolerant to work with a wide range of devices. And of course the communication protocol (baud rate, etc.) can be tweaked using the screen and user controls. Right now, there are some character dropping issues when driven at 115200 baud, but it sounds like those can eventually be worked out in the code. After I sent a PM to Kemonine asking for more details he posted a set of unedited demo videos which you might find interesting.
Visit his project thread for more information._________