Fujitsu Corporation

Norichika Kumamoto

Ryuta Tanaka

Toru Tsuruta

Ritsuko Tanaka

Yuji Nomura

Hideki Yoshizawa

Teruo Ishihara

Nobuyuki Iwasaki

A data transfer control system that can change the way of DMA transfers to meet the requirements of each application. The data transfer control system includes a DMA controller (DMAC) and a DMAC memory dedicated for DMA control purposes. The DMAC performs DMA transfers according to a DMA program stored in the DMAC memory. Each time a new DMA request is received, the DMAC saves its parameters in a DMA request parameter table, and each DMA request parameter table is registered with a DMA request management table. In this way, the received DMA requests are queued in the DMA request management table. They are executed in a first-in first-out fashion. The progress of ongoing DMA transfers are managed in a DMA channel status table disposed for each DMA channel.

System and method for controlling DMA data transfer

The present invention relates to a multiprocessor system, which comprises two or more processor elements to be executed by a common program, a control section for switching such plural processor elements one from another for execution by the common program, and a storing section storing handover information relating to the common program which information is to be handover from the one processor element to the another processor element. This not only optimizes each of the functions of the processor elements, but also achieves certain delivery or interchange of the information between these process or elements, and even reduces the power consumption.

Multiprocessor system, multiprocessor control method, and multiprocessor control program retaining computer-readable recording medium

An object of the present invention is to provide a programmable logic device which intends to reduce electric power consumption or heat generation sufficiently as a whole device while preventing a clock skew from being generated and retaining a processing speed of the device. To this end, according to the present invention, there is provided a device including logic blocks for carrying out logical operation, lines for connecting the logic blocks, line-changing means for changing the state of lines connecting the logic blocks by programming, a clock net for supplying a clock signal to each of the logic blocks, and clock control means for dynamically controlling switching between a clock signal supply mode and a clock signal stop mode for each logic block so that at least one non-active logic block of the logic blocks can be stopped from being supplied with the clock signal.

Programmable logic device and method of controlling clock signal thereof

A signal processing device is provided by connecting information processing units to each other using communication links and connecting the information processing units to each other and a host processor using an external bus. Parallel and pipe-line processing is accommodated by communication between the information processing units via the communication links and respective storage units of the information processing units and also by communication between the host processor and the information processing units via the external bus and the respective storage units. The host processor can communicate with the information processing units via the external bus through the respective storage units, the storage units being accessible as memory by the host processor. If each information processing unit is implemented on a single chip as an integrated circuit, the signal processing device can be incorporated in a computer in the same manner as conventional memory device are incorporated.

Signal processing device accessible as memory

A simulator can simulate a processor which performs pipeline processing of operation instructions, and performs operation processes in parallel, a number of the processes being larger than a number of the pipelines. The simulator simulates a passing operation in which a result of an operation processing obtained from execution of an operation instruction is output earlier than a result of another operation process obtained from previously started execution of another operation instruction, the passing operation occurring due to the number of execution cycles of each operation instruction which is executed in parallel with execution of other operation instructions.

Growing community of inventors

Kawasaki, Japan

Norichika Kumamoto