Arduino Value to Squirrel Code

I have a sensor hooked up to an Arduino Uno with an Imp shield. I’m trying to pass a value from Arduino code to the Imp (Squirrel Code), but can’t seem to find the documentation for this simple task. Documentation or code samples?

Here’s a good tutorial from SparkFun:

As an aside - many people find it much simpler to connect sensors directly to their imp rather than connecting their sensors to an Arduino, then passing the data to the imp.

Hope that helps!