Fujitsu Corporation

Hiroki Masuda

Koji Eto

Yoso Igi

Tetsuo Kawamata

A multiprocessor system is provided with main processors and secondary processors, and the processors are duplexed to form an active system and a standby system. A right to switch the system is given only to the main processors, and the secondary processors are operative to switch the system in accordance with the related system switching command, wherein data and control information are independently communicated between the main processors and the corresponding secondary processors belonging to the same active or standby system.

System for switching between processors in a multiprocessor system

A group of control registers for controlling a plurality of input output devices respectively are formed in random access memory which is connected to a microprocessor bus of an input output control device. A history of a program mode access from a central processing apparatus to the RAM is recorded in a first-in first-out memory (FIFO). The microprocessor of the input output control device reads an access information of the FIFO, accesses the group of the control registers on the RAM, and controls the input output device according to the read control information. Thus, control of a plurality of input output devices is carried out by one input output device.

Growing community of inventors

Yokohama, Japan

Hiroki Masuda