Psychophysics experiments often require passing messages and signals between different computers and devices. There are a number of methods that are generally used and the limitations of these methods are often a source of consternation for researchers.
Experiments designed to probe human temporal perception are particularly sensitive to timing errors in the apparatus. Therefore we have been developing a high resolution signal acquisition device for sending and receiving signals and doing some basic processing.
This post will be updated with details as we continue development but for now, here's a nice graphic of a digital signal sent and read, then displayed on an LCD screen attached to an Arduino Due. The sampling is at 1ms resolution.
After working with a variety of connections, creative wiring and cardboard boxes, Matt and I arrived at a far more modular solution to signal acquisition. The attached picture shows the repackaged signal acquisition device that contains 2 x Arduino Due, a touch screen and a Massachusetts Analog CVP attenuator. It's all made simpler by being in the standard Eurorack format.
The trace you can see is a simulated leftward saccade.
The code for the arduino is included below, feel free to use it in your own projects.