Image Number 3 for United States Patent #5631952.
An apparatus and method for a data communications device, such as a modem, having a sleep mode for conserving energy and an operational mode for data transmission, to transition from the sleep mode to the operational mode. The wake up method and apparatus respond to the receipt of serial data from a terminal, including response to existing terminal commands. The wake up method and apparatus also autobauds to the serial data transmit signal. The wake up and autobauding operations occur in a way that are transparent to the user.