Data transfer control device, electronic instrument, and data transfer control method

摘要

A data transfer control device having: a hub dedicated data storage section which stores a packet transferred between the data transfer control device and a hub; a packet transmission section which cyclically issues a token packet to the hub for asking whether the state of the hub has changed or not; a packet reception section which receives a response packet sent from the hub in response to the token packet; and a transfer controller which writes the response packet received by the packet reception section into the hub dedicated data storage section, and generates an interrupt which indicates that the state of the hub has changed.