Fujitsu Corporation

Fujitsu Microelectronics Limited

Fujitsu Vlsi Limited

Masatoshi Ohnishi

Yuji Yoshida

Koji Horibe

Takahiro Niwa

A host apparatus that adjusts consumption of a device in accordance with the power supply capability of the host apparatus. The host apparatus includes a plurality of communication ports and devices connected to each communication port. A host controller of the host apparatus communicates with the devices to acquire equipment information including the consumption current of each device. A current supply circuit supplies current to the devices connected to the communication ports. An MPU changes the current supplied from the current supply circuit to the plurality of devices when a total value of the consumption current of a device newly connected to the plurality of communication ports and the consumption current of each device for which connection with the plurality of ports has already been recognized exceeds the current that the current supply circuit is capable of supplying.

Host apparatus, device, and method for controlling communication system

In a SCSI device in a small computer system including a plurality of apparatuses, each apparatuses having a SCSI device connected to the apparatus by a MPU bus, and connected to each other through the SCSI device and a SCSI bus. Further each apparatus has an identification (ID) code, and the SCSI device includes; an ID setting register operatively connected to the MPU bus for setting the ID code of another device; an address decoder operatively connected to the ID setting register for decoding the ID code; a transfer parameter storage unit operatively connected to the MPU bus and the address decoder for storing the transfer parameters for all apparatuses constituting the small computer system, and divided into a plurality of memory blocks equivalent to number of the apparatuses to store the transfer parameters for each apparatus; a register operatively connected to the MPU bus for storing various data from the MPU bus; a read/write control unit for receiving a read/write signal and an address signal from the microprocessor, and outputting these signals to the ID setting register, the transfer parameter storage unit, and the register; a data FIFO connected between the SCSI bus and the MPU bus for temporarily storing data; and a transfer control unit operatively connected to the data FIFO and the transfer parameter storage unit for controlling the transfer of the data based on a request signal and an acknowledge signal from the other device through the SCSI bus.

Growing community of inventors

Kasugai, Japan

Masatoshi Ohnishi