Scripting Question

I know how to find the current value of a device, but would like to find all the possible values.

I'm butchering together a script that will take an input of say 'TV off' and send a numeric string, like '53' to the plugin via

Dim bSuccess as Boolean = hs.PluginFunction("UltraGCIR3", "", "SendIRById", New Object() {controlId})

Is this possible?