Download AutoArduino here.

Allows you to directly set and read Arduino pin states from Tasker.

AutoArduino connects to your Arduino through USB OTG, Bluetooth or Ethernet. Wifi support is possible so if there’s demand for it I can try to implement it.

Here are a few tutorials to get you started:

Turn a LED on or off

Read Button State

Control Pin with Button


And here are some video examples of what people have been doing with AutoArduino: