A semiconductor component is described which is capable of controlling transmission of information between a plurality of semiconductor components in a computer system. The semiconductor component comprises of a first signal generator capable of sending a signal of a first type over a shared line and a second signal generator capable of sending a signal of a second type over the line. It also comprises of a first logic device capable of controlling the first signal generator and a second logic device capable of controlling the second signal generator.
This is a continuation of application Ser. No. 08/590,954, filed Jan. 24, 1996, U.S. Pat. No. 5,706,444, which is a continuation of application Ser. No. 08/210,560, filed Mar. 18, 1994, issued Jul. 2, 1996 as U.S. Pat. No. 5,533,200.
An external interface circuit in an electronic device is capable of continuing data communication between other electronic devices through the first device even when a main body power source in the first device is cut off. In a computer main body, the main body power source and an IEEE-1394 interface are provided. Two external devices having IEEE-1394 interfaces are connected through the first interface. The interface of the computer main body has a power source control portion, a link layer control portion and a physical layer control portion. In the power source control portion, a power source detecting portion and a switch are arranged. When an input of power from the main body power source is detected, a power source detecting portion of the power source control portion controls the switch so that the power from the main body power source is supplied to the physical layer control portion. When input of power from the main body power source is not detected, the power source detecting portion controls the switch for supplying power from a power source of two external devices having IEEE-1394 interfaces to the physical layer control portion of the main body.
A system and method for receiving and storing information transmission units such as electronic mails, where newly received transmission units are automatically allocated to groups in a storing means, employing a weighted sum with respect to the determination of allocation decision parameters from the comparison between the structure of previously stored transmission units and the newly to be stored transmission units.
