I'm working on a project involving a tablet computer running an OpenSim client (OpenSim is an open source alternative to Second Life). I want to use the physical orientation of the tablet to control the direction that the camera in OpenSim is pointing.
I have an Uno with an ADXL335 accelerometer. Getting readings from the accelerometer to the computer was no problem - I simply copy & pasted an example & did 'cat /dev/ttyACM0' & watched the readings stream by.
My question now is how best to actually use these readings. OpenSim clients have joystick support so I figured the simplest approach would be to 'emulate' a joystick using software, feed in the readings from the Uno & have the OpenSim client use that 'virtual' joystick. However I have also noticed that there is also an alternative firmware for the Uno to make it present itself to the host computer as a joystick.
PaulS:
Why not modify OpenSim to give it the ability to connect to, and read from, the serial port?
Ah, should've mentioned that initially. All of the OpenSim clients are based on code from a previous version of the Second Life viewer which was released to the community. However because of the licensing of the release you are disallowed from contributing code to the OpenSim server if you have looked at any of the client code - presumably over fears that code/IP from Linden (the makers of Second Life) will end up in OpenSim. I intend to contribute to the server in the future so would like to stay clear of modifying a client. Awkward, I know.
The other justification is that if I modify a client, then my project will only work with that one client, whilst there are several popular ones in use.
The USB HID joystick firmware that I linked to appears to work quite well & will let me get things rolling quickly, but in the long run I would like to revert the Arduino to its regular USB serial mode so that I can use it for more than just sending joystick controls, so I will keep checking this thread in case anybody happens to have any ideas.