JP2584903B2 - External device control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external device control system of an information processing apparatus in which a plurality of programs for controlling one external device operate in parallel. With the recent increase in functionality, miniaturization, and cost reduction of information processing devices, one information processing device uses the same external device and performs different processing without increasing the number of hardware components. It is required to operate a plurality of control programs.

For this reason, it is necessary to perform exclusive control between programs using the same external device.

[0003]

2. Description of the Related Art In a conventional external device control method of an information processing apparatus, only one control program uses an external device on one information processing apparatus. The number of external devices is increased to correspond to one.

[0004]

However, in such a conventional external device control method, when a plurality of control programs using one external device are operated by the information processing apparatus, each of the control programs corresponds to each control program. External devices must be connected by the specified number, and the hardware configuration of the information processing device is complicated, and there is a problem that miniaturization and cost reduction are prevented. The present invention has been made in view of such conventional problems, and has as its object to provide an external device control method that can efficiently use one external device with a plurality of control programs that operate in parallel. .

[0005]

FIG. 1 is a diagram illustrating the principle of the present invention. First, the present invention relates to an external device control method of an information processing device 3 in which an external device 1 is connected via an input / output port (I / O port) 2 for control. Control programs 4a to 4
n has a unique priority level for acquiring the execution right of the external device, and manages the execution of the external device 1 by the plurality of control programs 4a to 4n based on the priority level of the execution right of each of the control programs 4a to 4n. The monitor program 5 is provided.

More specifically, a command area 6 for writing a command of a control program for using the external device 1 and a status area 7 for writing status information indicating the status of the external device 1 to the input / output port 2. Is provided. When the control program 4a of a higher level than the control program 4b which is currently writing a command in the command area 6 tries to use the external device 1, the monitor program 5 executes a command of a lower level in the command area 6. Is saved in the lower-level command save area 8a of the higher-level control program 4a, and then the command of the higher-level control program 4a is written to use the external device 1.

When the use of the external device 1 by the higher-level control program 4a is completed, the monitor program 5 transfers the command saved in the lower-level command save area 8a of the higher-level control program 4a to the input / output port 2. The command is restored to the command area 6 so that the external device 1 can be used by lower-level commands. Further, the monitor program 5 refers to the status area 7 of the input / output port 2 when any of the plurality of control programs 4a to 4n tries to use the external device 1, and when the external device 1 is in use, If so, command writing to the command area 7 is prohibited, and if the external device 1 is not in use, command writing to the command area 7 is permitted.

As a practical example of the present invention, for example, the information processing apparatus 1 is a line control adapter device for connecting a terminal unit to a communication line. And a communication procedure control program for controlling a transmission / reception procedure as a lower level control program, and a DMA controller for transferring data between memories of two devices by means of two control programs. Commonly used as device 1.

[0009]

According to the external device control system of the present invention having such a configuration, each control program using the external device is provided with a lower-level command save area, and is provided with an I / O port for controlling the external device. If it is possible to issue a command by checking the status area, save the contents of the command area to the lower-level command save area of the control program, and then issue the own command.After the command is completed, execute the lower-level command save area. The contents are restored to the command area.

Therefore, even if the execution right of the external device is transferred to a higher-level program while a plurality of control programs using the external device are operating in parallel, after the processing of the high-level program is completed, the monitor program executes When the execution right is returned, the lower-level program can be used by the external device continuously, and a plurality of control programs in one information processing device can efficiently use one external device.

[0011]

FIG. 2 is a block diagram of an embodiment showing an embodiment of the present invention, in which a line control adapter device connected to a terminal body as an information processing device is taken as an example. In FIG. 3, reference numeral 3 denotes a line control adapter device as an information processing device, which is provided between the communication line 9 and the terminal main body 10.

The line adapter device 3 is provided with a communication procedure control program 4b.
Uses the DMA controller 1 as an external device to perform DMA transfer of transmission data and reception data between the memory of the line control adapter device 3 and the memory of the terminal device 10 connected via a shared bus. Do. The line control adapter device 3 is provided with a debugger program 4a, and the debugger program 4a is a DMA as an external device.
Using the controller 1 to perform debugging commands, for example, setting of breakpoints, display of memory contents, etc., and transfer of debug results between the memory of the line control adapter device 3 and the memory of the terminal device 10. Thus, a debugging function for program development and maintenance on the line control adapter device 3 is realized.

Here, the debugger program 4a is a high-level control program having a high priority in execution right to use the DMA controller 1, while the communication procedure control program 4b is a low-level control program. Further, a lower-level command save area 8a is provided in the higher-level debugger program 4a.

A command area 6 and a status area 7 are provided at the I / O port 2 for the DMA controller 1 of the line control adapter device 3. The command area 6 includes a debugger program 4a or a communication procedure control program 4b for using the DMA controller 1.
Command is written. In the status area 7, status information indicating the status of the DMA controller 1 is written.

The line control adapter device 3 is further provided with a monitor program 5, and the monitor program 5 manages the exercise of the execution right assigned a priority level in a parallel operation state of the plurality of control programs 4a and 4b. Specifically, when the DMA controller 1 is used by an arbitrary control program, the status area 7 of the I / O port 2 at that time is read, and it is checked whether the DMA controller 1 is being used by another control program. I do. If it is in use, wait for the end of use.

When the DMA controller 1 becomes usable, the monitor program 5 checks whether the control program which has newly issued a use request is at a higher level than the control program which has already written a command in the command area 2. If it is at a higher level, the command area 6
Is saved in the lower-level command saving area 8a provided in its own control program, and then its own command is written to use the DMA controller 1.

Of course, when the use of the DMA controller 1 is completed, the saved lower-level command is restored to the command area 6, and the lower-level control program enables the use of the DMA controller. Next, the processing operation of the embodiment of FIG. 2 will be described with reference to the flowchart of FIG. Assuming that a request to use the DMA controller 1 is issued from the debugger program 4a, the monitor program 5 first reads the status area 7 of the I / O port 2 in step S1, and the DMA controller 1 as an external device in step S2. Check if it is in use.

If the DMA controller 1 is not in use, the flow advances to step S3 to read the command area 7 of the I / O port 2, and if a lower level command has been written, the lower level of its own control program has been written. It is set in the command save area 8a. Subsequently, after writing its own command control parameters in the command area 7 in step S4, a command is written in the command area 7 in step S5 to start the DMA controller 1 as an external device. Thus, the debugging process of the terminal main unit 10 by the debugger program 4a is started by the DMA transfer using the DMA controller 1.

During the debugging process, I / O is performed in step S6.
The status area 7 of the port 2 is read and step S
In step 7, it is checked whether the processing is completed. When the debugging process is completed, the process proceeds to step S8, where the lower-level command set in the lower-level command save area 8a of the debugger program 4a is written and restored in the command area 6 of the I / O port 2, and the lower-level command, That is, the DMA controller 1 can be used by the communication procedure control program 4b.

In this flowchart, steps S1 to S8
At any point in time, if a higher-level control program issues a request to use an external device, the execution right is transferred to the higher-level control program at that point. In steps S5 to S7, the use of the external device by another control program becomes impossible. However, the use of the external device by the lower-level control program is interrupted after activation, and the higher-level control program is not limited thereto. May be used.

In the above embodiment, a case is described in which a plurality of control programs of the line control adapter device use a DMA controller (external device) for performing DMA transfer with the terminal unit. The present invention can be directly applied to an appropriate device as long as one external device is used for a plurality of control programs of the processing device. In the above embodiment, two control programs, an upper control program and a lower control program, are taken as examples. However, three or more control programs can be realized in exactly the same manner by giving each control program a unique priority level.

[0022]

As described above, according to the present invention, an external device can be used efficiently by a plurality of control programs without adding an external device. The hardware configuration can be greatly reduced, and a system with high cost performance can be constructed at the same time as miniaturization.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a configuration diagram of an embodiment of the present invention.

FIG. 3 is a flowchart showing a processing operation of the present invention.

[Explanation of symbols]

1: External device (DMA controller) 2: Input / output port (I / O port) 3: Information processing device (line control adapter device) 4a: Higher level control program (debugger program) 4b: Level localization control program (communication) Procedure control program) 5: Monitor program 6: Command area 7: Status area 8a, 8b: Lower-level command save area 9: Communication line 10: Terminal body

Claims (5)

(57) [Claims] 1. An external device control method for an information processing device (3) in which an external device (1) is connected via a control input / output port (2), wherein the external device (1) is commonly used. the plurality of the control program for an information processing apparatus (3) to (4a to 4n), the Ru to have a unique priority level to acquire the right to execute the external device
Both have lower priority levels than their own
Save area for saving commands of the control program
(8a to 8n), and the plurality of control programs (4
a to 4n) to manage the execution of the external device (1) based on the priority level of the execution right of each control program (4a to 4n), and to execute the control program (4a to 4n).
n) Run a control program with a lower priority level
During the execution, the control program having the lower priority level is used.
Command in the save area (8a to 8n)
The control program (4a to 4a) to be executed
An external control device provided with a monitor program (5) for executing n) . 2. An external device control system according to claim 1, wherein a command of a control program for using an external device is written to said input / output port. And a status area (7) for writing status information indicating the state of the external device (1). The monitor program (5) is a control program which is currently writing a command in the command area (6). (4b) When the higher-level control program (4a) attempts to use the external device (1), the lower-level commands in the command area (6) are transferred to the lower-level commands of the higher-level control program (4a). After saving to the level command save area (8a), a command of the higher-level control program (4a) is written to use the external device (1). External device control method. 3. The external device control system according to claim 2, wherein the monitor program (5) is configured to execute the high-level control when the use of the external device (1) by the high-level control program (4a) is completed. An external device storage system characterized in that a command saved in a lower level command save area of a control program (4a) is restored to a command area of an input / output device (2) so that a lower level command can be executed. 4. The external device control system according to claim 1, wherein the monitor program (5) is used when one of a plurality of control programs (4a to 4n) tries to use the external device (1). Refers to the status area of the input / output port (2), and if the external device (1) is in use,
An external device control method, wherein command writing to the command area (7) is prohibited, and command writing to the command area (7) is permitted when the external device (1) is not in use. . 5. The external device control system according to claim 1, wherein said information processing device is a line control adapter device for connecting a terminal body to a communication line. The line control adapter device is provided with a debugger program for debugging the terminal as a high-level control program, and a communication procedure control program for controlling a transmission / reception procedure as a lower-level control program. An external device control system, wherein a DMA controller for transferring data between memories of two devices is commonly used as an external device (1).