JPH0527954A - Computer system - Google Patents

Abstract

PURPOSE:To provide the computer system which can simultaneously activate respective OS, can realize the operation of communication between the respective OS and can develop an application program freely operated between the respective OS concerning the system in a system to activate the various kinds of plural OS. CONSTITUTION:When a switch key 7a of a keyboard 7 is operated, the switching of various OS is instructed. Corresponding to this switching instruction, an interface software stored in a memory 2 executes memory control to change the arrangement of the memory 2 for each OS, and the respective OS are mutually switched and activated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal computer, for example, and relates to a computer system capable of starting a plurality of operating systems of different types.

[0002]

2. Description of the Related Art Conventionally, in a computer system such as a personal computer, an operating system (OS) such as MS-DOS (registered trademark) stored in a hard disk or a floppy disk is set in a main memory and operated by the OS. Application program is executed.

By the way, there is a computer system that can start a plurality of different OSs such as MS-DOS and OS / 2. In such a system, one of the operating OSs is reset by hardware (switching of system power supply) and the other OS is activated. Therefore, in a system operating with a unique OS, when it is desired to start an application program that operates with a different OS, there is an advantage that a process for porting for the unique OS is unnecessary.

[0004]

In a system in which a plurality of different kinds of OSs are activated, one of the OSs can be selectively activated. With such a system, it is possible to freely use application programs that run on different OSs. However, since the switching operation of each OS requires a hardware reset process, there is a drawback that the efficiency of the entire system decreases.

It is an object of the present invention to realize a mutually efficient switching operation between OSs in a system of a system in which a plurality of different OSs are started up, and consequently improve the system performance. It is to provide a computer system capable of doing so.

[0006]

According to the present invention, there are provided a memory means for storing a plurality of different OSs, an input means for issuing a switching instruction for switching each OS, and an interface means for realizing an interface between the OSs. It is a computer system equipped with.

[0007]

According to the present invention, when a switching instruction is given by the input means, the interface means executes memory control for changing the memory arrangement of the memory means for each OS, and switches and starts each OS mutually.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a computer system according to the embodiment. This system includes a processor (CPU) 1, a memory 2 capable of storing a plurality of OSs, a clock generator 3, and a gate array 4 constituting a controller.

The memory 2 includes a main memory 2a for storing a main OS (OS-A) and an OS different from the main OS.
Extended memory 2 used when (OS-B) is used
b. The clock generator 3 is the CPU 1
And a clock required for the operation of the gate array 4 is generated. The gate array 4 is an LSI including a memory controller 4a that controls the memory 2 and an I / O controller 4b that controls various I / O devices. The memory controller 4a executes bank switching control between the main memory 2a and the extension memory 2b.

Further, this system includes a liquid crystal display (LCD) 5, an LCD controller 6, a keyboard 7,
Keyboard controller 8, floppy disk device (FDD) 9, floppy disk controller (F
DC) 10, printer 11, printer controller 12
And a video RAM (V-RAM) 13.

The LCD controller 6 is a V-RAM 13
The control operation of displaying the display data expanded on the screen of the LCD 5 is performed. The keyboard 7 has a switching key 7a for instructing switching of the OS in addition to various character keys and function keys. Keyboard controller 8
Converts a key input signal from the keyboard 7 into a key code and outputs it to the I / O controller 4b of the gate array 4. The FDC 10 controls the operation of the FDD 9, which is an external storage device, and controls the CPU 1 through the I / O controller 4b.
Record and play back data with and. Next, the operation of the embodiment will be described.

First, when the system is powered on, C
PU1 is reset and executes the initial check processing of the system. In addition, IPL (initialprog)
RAM-loader) reads the OS-A stored in the FDD 9 and sets it in the main memory 2a.

OS-A set in the main memory 2a
Is initialized and activated (step S1), the CPU1
Executes an application program operated by OS-A (step S2).

Here, OS-B, which is different from OS-A, is F
It is read from the DD 9 and set in the expansion memory 2b of the memory 2. Therefore, two different OSs are set in the memory 2. In this state, when the switching key 7a of the keyboard 2 is operated (YES in step S3), the interface software set in the main memory 2a is activated as shown in FIG. The interface software is
It is a program for performing mutual switching processing between OS-A and OS-B and communication processing between each OS.

By starting the interface software, the contents of various registers holding various control information of OS-A are saved (step S4). The various registers are PSW (program status word) registers and the like. Further, as shown in FIG.
The jump vector B for OS-B of the expansion memory 2b is set, and interrupts are disabled (step S
5).

Memory controller 4a of gate array 4
Allocates the extension memory 2b from the address 0 to make it effective (step S6). That is, the memory controller 4a executes bank switching from the main memory 2a to the expansion memory 2b, and performs control to change the memory arrangement of the memory 2.

Further, the interrupt is enabled (step S7), and OS-B is initialized and activated (step S8). As a result, the CPU 1 executes the application program operated by the OS-B (step S9).

When the execution of the application program by the OS-B is completed (YES in step S11)
S), the interface software starts again, and
It returns to S-A (step S12). That is, as shown in FIG. 2A, the jump vector A for OS-A of the main memory 2a is set and the saved OS-A is saved.
Restore various registers of.

By the way, when the interface software is started in order to communicate with OS-A while the application program is being executed by OS-B,
The interface software calls OS-A (C
ALL) is executed (YE in step S10)
S).

In the communication process between the OSs, the interface software saves the contents of various registers holding various control information of the OS-A as shown in FIG. 4 (step S20). Further, the saved various registers of the OS-A are restored (step S21), and the program parameters and the like are copied into the interface software as needed (step S22).

The interface software disables interrupts (step S23), and the gate array 4
I / O command is output to the memory controller 4a. With this memory controller 4a, the expansion memory 2
b is returned for OS-A (step S24). After that, the interrupt is enabled (step S25), and the OS-A system call process is executed (step S26). This processing is to simulate that an application program running on OS-B calls OS-A.

Further, the interface software disables interrupts (step S27) and outputs an I / O command to the memory controller 4a of the gate array 4. The memory controller 4a allocates the expansion memory 2b from the address 0 to make it effective (step S28). That is, the expansion memory 2b is changed to the memory mapping for OS-B. After that, the interrupt is enabled (step S29), and the saved various registers of the OS-B are restored (step S30).

In this way, when the switching key 7a for instructing the switching of the OS is operated, the interface software is activated. With this interface software, the memory controller 4a executes, so to speak, a bank switching operation of the memory 2. Therefore, the interrupt vectors A and B for booting each OS are independently stored in the memory 2
, And different types of OSs can be switched to each other. This allows each OS to be switched by switching the system power supply.
Need not be switched, and it is possible to easily switch according to the operation of the switching key 7a.

Further, the interface software makes it possible to realize communication between the OSs by making a system call of the other OS while the other OS is being activated. This makes it possible to develop an application program that operates freely between the OSs.

[0026]

As described above in detail, according to the present invention, in a system of a method of booting a plurality of different OSs, it is possible to realize an efficient switching operation between the OSs. As a result, communication between OSs is realized, and it is possible to develop application programs that freely operate between OSs. Therefore, the performance of the system can be improved as a result.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a computer system according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram for explaining a configuration of a memory according to the same embodiment.

FIG. 3 is a flowchart for explaining the operation of the embodiment.

FIG. 4 is a flowchart for explaining the operation of the embodiment.

[Explanation of symbols]

1 ... CPU, 2 ... memory, 2a ... main memory, 2b ...
Extended memory, 4 ... Gate array.

Claims (1)

Claim: What is claimed is: 1. A memory means for storing a plurality of operating systems of different types, an input means for issuing a switching instruction for switching between the operating systems, and a switching instruction by the input means. Then, a computer system comprising: interface means for executing a memory control for changing the memory arrangement of the memory means for each of the operating systems, and for switching and starting the operating systems with each other.