Hitachi, Ltd.

Hitachi Computer Engineering Co., Ltd.

Yoshitake Nakaosa

Megumu Kondo

Masahiro Kainaga

Kousuke Sakoda

Fumiya Murata

Shigemi Adachi

Hidehiko Akita

Hidenori Yamada

Yoshiki Fujioka

Sadao Ohashi

Yoshihisa Shirakabe

Hideo Ohchi

In an operating system generation method for a computer, at a system initiation, a kernel as the basic portion of the operating system is linked with a plurality of input-output drivers controlling input-output devices. A directory name of each driver and an address thereof in a main memory are stored in a table within the kernel with a correspondence established therebetween, which allows mutual references between the kernel and the input-output drivers and which hence enables the input-output drivers to be generated in an independent fashion with respect to the kernel. As a result, the user can incorporate desired input-output drivers into an operating system depending on a hardware configuration of the computer system.

Operating system generation method

In an operating system generation method of a computer, a symbolic name is converted into an identification code, which is further converted into an address. This enables an inter-reference operation to be achieved between a kernel and input/output device drivers, thereby independently generating the input/output device drivers and the kernel. As a result, depending on the hardware configuration of the user system, input/output device drivers can be incorporated into the operating system.

Method for generating an operating system by a static link-editor

A method for emulating programs in a system includes a plurality of first and second data processors having different instruction word sets. An instruction which interrupts the operating system on the first data processor is defined. When the instruction is detected in a program running on the first data processor, it is determined whether or not the instruction is an instruction associated with an input/output macro instruction. If it is found, as a result of the determination, that this is the case, an interrupt is caused in a program running on the second data processor which controls the emulation, and the input/output macro instruction output from an emulated program is translated into an input/output macro instuction for the operating system, thereby implementing an emulation with a minimized overhead.

Emulation method

A method of processing a plurality of different code systems for an information processing apparatus including an operating system, comprises a step of inputting a source program, and a compiling step of analyzing meaning of the source program to thereby create a series of instructions and data required for executing a processing equivalent to the meaning of the source program. The compiling step includes a sub-step of transforming character type constants to a first code system occupying region including a first number of bits and transforming character string constants to a second code system occupying a region including a number of bits which is equal to product of a sum of the number of characters of the character string constants plus one and multiplied with the first bit number so that character type variables designated in the source program correspond, respectively, to the region of the first bit number while a character type array corresponds to a region including a number of bits which is equal to a product resulting from multiplication of the first bit number with the number of elements of the array.

Method of processing a plurality of code systems

Growing community of inventors

Yokohama, Japan

Yoshitake Nakaosa