In a main computer system coupled to an auxiliary display device, described is an interface set for implementation by an auxiliary display device driver, to couple the driver to an auxiliary display platform. Commands received from the auxiliary display platform may be handled by code external to the driver, such as a class extension object. For example, the class extension object may interpret and/or translate commands received from the auxiliary display platform into a format understood by the driver code. The auxiliary display device driver may then provide corresponding command information including data to the auxiliary display device via the transport. Event data may be returned from the auxiliary display device driver via the interface set to the class extension object, such that corresponding event information, e.g., received at the auxiliary display device, may be returned to the auxiliary display platform.