BIDI_SET_DEVICE_ID(23h) sets the printer's device ID. The protocol converter calls PrtSet with this command structure to notify the spooler of the device ID of an attached printer.

BIDI_SET_DEVICE_ID(23h) is used when the port driver is unable to determine the device ID during BIDI_Q_PORT(800Bh), and allows the protocol converter to retrieve the device ID.