''iocore_gpo: <name> | <channel> | on/off | //<duration>//''

Assuming the named node is a Visual Productions’ ioCore2, uses the ioCore API to control the GPO ports on that node.

  * **name** is the name of the node to be controlled
  * **channel** is the number of the GPO to be controlled
  * The 3rd field must be either **on** (closed) or **off** (open), and sets the state of the GPO
  * **duration is optional** – if present, the GPO will be pulsed in the direction indicated for the duration in milliseconds.