JPH11161591A - Data communication equipment, data communication method, storage medium and device driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate data communication and to excellently suppress the stagnation of a processing and the generation of malfunctions due to the generation of an error. SOLUTION: When an ID request is transmitted to a virtual device driver (S1), in the case that the virtual device driver supports a nonstandard protocol, an original ID is returned. In this case, the ID is received in S3, and when it is the original ID (S5: YES), reception by the nonstandard protocol is instructed to the virtual device driver (S13). Then, the data communication is accelerated. In the case that the ID is different from the original ID though the ID is received (S7: YES) and in the case that the ID is not returned (S9: YES), the reception by a standard protocol is instructed to the virtual device driver (S15). Then, the generation of the error or the like is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication device and a data communication method for performing data communication with an external device via an I / O port by a communication method supported by a device driver, and a device or a method thereof. The present invention relates to a storage medium and a device driver for implementing the method.

[0002]

2. Description of the Related Art Conventionally, personal computers (hereinafter, referred to as personal computers).
There is an I / O port provided in such as
For example, a parallel port was dedicated to output. However, in recent years, it has been practiced to expand the parallel port to be bidirectional and use it for bidirectional data communication to cope with multifunctional personal computers and external devices. For example, in recent years,
2. Description of the Related Art A printer having a function as an image scanner (hereinafter, simply referred to as a scanner) has been developed. In order to realize the function as a scanner, a virtual device driver for inputting / outputting data via an I / O port (parallel port) and a scanner (1 of the printer) via the virtual device driver A driver (scanner driver) for reading data from the function) is used.

[0003] Here, the data transmitted from the scanner has a relatively large capacity, and a large amount of time is required for such data communication. Therefore, each scanner maker employs a unique non-standard protocol that enables high-speed data communication, and attaches a scanner driver and a virtual device driver supporting the non-standard protocol to the scanner. By installing the scanner driver and the virtual device driver in its own personal computer, the user can perform data communication using a non-standard protocol between the scanner and the personal computer, thereby reducing the time required for data communication.

[0004]

However, although a plurality of scanner drivers can be installed in a personal computer, usually only one virtual device driver can be installed. Therefore, when a new scanner driver and a new virtual device driver are installed in the personal computer, the already used virtual device driver cannot be used. Therefore, when trying to perform data communication using a non-standard protocol using a scanner driver that has been used before, the virtual device driver may not support the non-standard protocol, and an error occurs and processing stops.

Further, if the newly installed virtual device driver supports another non-standard protocol and the control code coincides with the previously used non-standard protocol, the scanner or the personal computer may malfunction. Wake up. Therefore, the present invention provides a data communication device and a data communication method that can speed up data communication by a non-standard communication method, and can appropriately suppress stagnation of processing and occurrence of malfunction due to occurrence of an error. It has been made to provide a storage medium and a device driver for realizing them.

[0006]

Means for Solving the Problems and Effects of the Invention According to the first aspect of the present invention, there is provided a communication method between an external device and an external device via an I / O port by a communication method supported by a device driver. A data communication device that performs data communication by using the device driver; and a determination unit configured to determine whether the device driver supports a target nonstandard communication method. When it is determined that the standard communication method is supported, the device driver includes communication method instruction means for instructing to perform data communication with the external device by the non-standard communication method, When the determining means determines that the device driver does not support the non-standard communication method, the device driver does not support the non-standard communication method. The standard communication method are is characterized by performing data communication with the external device.

[0007] In the present invention thus configured, the judging means judges whether or not the device driver supports a target nonstandard communication system. Then, when the determining means determines that the device driver supports the non-standard communication method, the communication method instruction means transmits the device driver to the external device by the non-standard communication method. To perform data communication. Therefore, data communication is performed between the device driver and the external device by the non-standard communication method, and the speed of the data communication can be increased.

When the determining means determines that the device driver does not support the non-standard communication method, the communication method instructing means does not issue the instruction. For this reason, the device driver performs data communication with the external device according to a standard communication method supported by the device driver as usual. Therefore, it is possible to prevent data communication using the non-standard communication method from being performed via a device driver that does not support the non-standard communication method.

As described above, according to the present invention, when the device driver supports the non-standard communication method, the device driver supports the data communication by the non-standard communication method, and the device driver supports the non-standard communication method. When there is no data communication, data communication using a standard communication method can be executed. Therefore, the speed of data communication can be increased, and stagnation of processing and occurrence of malfunction due to occurrence of an error can be favorably suppressed.

According to a second aspect of the present invention, there is provided a data communication method for performing data communication with an external device via an I / O port according to a communication method supported by a device driver. When determining that the device driver supports the non-standard communication method, and by the determination processing to determine whether the non-standard communication method is supported, by the determination processing,
And a communication system instruction process for instructing the device driver to perform data communication with the external device by the non-standard communication system. When it is determined that the communication method is not supported, the device driver performs data communication with the external device according to a standard communication method supported by the device driver.

In the present invention having the above-described structure, first,
Through the determination process, it is determined whether the device driver supports the target non-standard communication method. When the device driver determines that the device driver supports the non-standard communication method by the determination process, the device driver communicates with the external device using the non-standard communication method by the communication method instruction process. Instructs to perform data communication. Therefore, data communication is performed between the device driver and the external device by the non-standard communication method, and the speed of the data communication can be increased.

When the device driver determines that the non-standard communication method is not supported by the determination processing, the instruction is not given by the communication method instruction processing. For this reason, the device driver performs data communication with the external device according to a standard communication method supported by the device driver as usual. Therefore, it is possible to prevent data communication using the non-standard communication method from being performed via a device driver that does not support the non-standard communication method.

As described above, according to the present invention, when the device driver supports the non-standard communication method, the device driver supports the data communication by the non-standard communication method, and the device driver supports the non-standard communication method. When there is no data communication, data communication using a standard communication method can be executed. Therefore, similar to the first aspect of the present invention,
It is possible to increase the speed of data communication and satisfactorily suppress stagnation of processing and occurrence of malfunction due to occurrence of an error.

According to a third aspect of the present invention, there is provided a storage medium storing a computer program for performing data communication with an external device via an I / O port in a communication system supported by a device driver. A determination process for determining whether the device driver supports a target non-standard communication method, and the determination process determines that the device driver supports the non-standard communication method. And a communication mode instruction process for instructing the device driver to perform data communication with the external device by the non-standard communication mode. If it is determined that the device does not support the standard communication method, the device driver supports it. It is characterized by storing a computer program to perform data communication with the external device by semi-communication method.

Since the storage medium of the present invention is configured as described above, if a control means such as a computer executes a computer program stored in the present invention, a second aspect of the present invention is provided.
The following processing can be performed similarly to the described invention. That is, first, it is determined whether or not the device driver supports the target non-standard communication method by the determination processing. When the device driver determines that the device driver supports the non-standard communication method by the determination process, the device driver communicates with the external device using the non-standard communication method by the communication method instruction process. Instructs to perform data communication. In this case, data communication can be speeded up as described above.

If the device driver determines that the non-standard communication method is not supported by the determination processing, the instruction is not given by the communication method instruction processing. For this reason, the device driver performs data communication with the external device according to a standard communication method supported by the device driver as usual. Therefore, it is possible to prevent data communication using the non-standard communication method from being performed via a device driver that does not support the non-standard communication method.

For this reason, if the storage medium of the present invention is used for control means such as a computer, if the device driver supports a non-standard communication system, data communication using the non-standard communication system is performed. When the device driver does not support the above non-standard communication method, data communication using the standard communication method can be executed. Therefore, the speed of data communication can be increased, and stagnation of processing and occurrence of malfunction due to occurrence of an error can be favorably suppressed.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the determination processing indicates to the device driver that the device driver supports the non-standard communication system. An identification information requesting process for requesting notification of identification information; and a notification determination process for determining whether or not the device driver has notified the identification information after the identification information requesting process. When it is determined that the identification information has been notified by the processing, it is determined that the device driver supports the non-standard communication method, and when it is determined that the identification information has not been notified by the notification determination processing, And determining that the device driver does not support the non-standard communication method.

Therefore, if the control means such as a computer executes the computer program stored in the present invention, the judgment processing described in claim 3 can be performed as follows. That is, first, a request is made to notify the device driver of the identification information by the identification information request processing. The identification information indicates that the device driver supports the non-standard communication method. Thereafter, it is determined whether or not the identification information has been notified from the device driver by a notification determination process. The determination processing of the present invention determines that the device driver supports the non-standard communication method when it is determined that the identification information has been notified by the notification determination processing based on the result of the above processing. If it is determined by the notification determination process that the identification information has not been notified, it is determined that the device driver does not support the nonstandard communication method.

The form of the judgment by the judgment processing according to claim 3 may be various forms other than the same form as the present invention. For example, send some control code to the device driver by the above non-standard communication method,
If no error occurs, it can be determined that the device driver supports the non-standard communication method. However, in this case, if the device driver supports another non-standard communication method and the control code coincides with the control code used in the other non-standard communication method, an accurate judgment is made. Becomes difficult.

On the other hand, according to the present invention, it is determined whether or not the device driver supports the non-standard communication method according to whether or not the device driver has notified the identification information. . For this reason, in the present invention, the above determination can be made more accurately, and further, data communication is performed by the non-standard communication method via a device driver that does not support the non-standard communication method. Can be more reliably prevented. Therefore,
If the storage medium of the present invention is used for a control means such as a computer, in addition to the effect of the third aspect of the present invention, there is an effect that stagnation of processing and occurrence of erroneous operation due to occurrence of an error can be more effectively suppressed. Occurs.

It is to be noted that if the same limitation as that applied to the determination processing according to claim 3 is applied to the determination means described in claim 1 or the determination processing described in claim 2, the present invention will be described. Similar actions and effects are produced. According to a fifth aspect of the present invention, in addition to the configuration of the third or fourth aspect, when the device driver determines that the non-standard communication method is not supported by the determination processing, the device driver does not support the non-standard communication method. The communication system instruction process includes a process of instructing the device driver to perform data communication with the external device using a standard communication method.

Therefore, if a control means such as a computer executes a computer program stored in the present invention, the following processing can be performed in addition to the processing described in claim 3 or 4. That is, when the device driver determines that the non-standard communication method is not supported by the above-described determination processing, the communication method instruction processing performs data communication with an external device using the standard communication method supported by the device driver. Like communicating
The device driver can be instructed. Therefore, when the device driver does not support the non-standard communication method, data communication with an external device using the standard communication method supported by the device driver can be performed more reliably.

Therefore, when the storage medium of the present invention is used for a control means such as a computer, in addition to the effects of the third and fourth aspects, stagnation of processing and occurrence of erroneous operations due to occurrence of errors are further reduced. The effect of being able to suppress well is produced. The communication system instruction means according to claim 1 or the communication system instruction processing according to claim 2 is subject to the same restrictions as those applied to the communication system instruction processing according to claim 3 or 4 in the present invention. In this case, the same operation and effect as those of the present invention are produced.

According to a sixth aspect of the present invention, there is provided a device driver having the same input / output function as a standard device driver supporting a standard communication system, wherein a non-standard communication system is used in addition to the standard communication system. Support,
It has a function of notifying the upper-level device of identification information indicating that the non-standard communication method is supported in response to a request from the higher-level device.

Since the present invention has the same input / output functions as a standard device driver, it can be easily used in place of the standard device driver. Further, the present invention supports a non-standard communication system in addition to the standard communication system. Then, in response to a request from the higher-level device, identification information indicating that the non-standard communication method is supported can be notified to the higher-level device.

For this reason, the upper-level device determines whether or not the notification has been made after the request has been made, so that the device driver of the present invention can easily support the non-standard communication method. You can judge. That is, the same processing as the determination processing according to claim 4 can be easily executed. If the higher-level device supports the non-standard communication method, data communication can be speeded up by the communication method. If the higher-level device does not support the non-standard communication method, the standard method can be used. Depending on the communication method, data communication can be performed without causing stagnation of processing or occurrence of malfunction due to occurrence of an error. Therefore, according to the present invention, the speed of data communication can be increased, and the stagnation of processing and the occurrence of erroneous operations due to the occurrence of errors can be satisfactorily suppressed.

[0028]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the overall configuration of a system to which the present invention is applied. As shown in FIG.
This system is mainly composed of a personal computer (personal computer) 1 including a CPU, a ROM, a RAM, and the like.
The personal computer 1 is connected with a keyboard 3, a mouse 5, and a printer 7. The personal computer 1 is a CRT 1a
The printer 7 is a well-known printer with a scanner which has been developed in recent years.

Next, FIG. 2 is an explanatory diagram showing a hierarchical structure of software in the personal computer 1. These softwares are generally installed in a storage device such as a hard disk device, and are loaded on a RAM as needed. As shown in FIG. 2, above the OS (Operating System) 10, an image input application 11 for inputting an image via various scanners and a printing application 12 for printing via various printers are provided. And have been installed. OS10
Below the CRT driver 1 that drives the CRT 1a
5, a keyboard driver 16 for driving the keyboard 3,
A mouse driver 17 for driving the mouse 5, a plurality of scanner drivers 21 and 23 for driving various scanners, and
A plurality of printer drivers 25 for driving various printers,
27 are installed.

The CRT driver 15 is connected to the CRT 1a in the housing of the personal computer 1, and the keyboard driver 1
The mouse driver 6 and the mouse driver 17 are connected to the keyboard 3 and the mouse 5 via dedicated connectors (not shown), respectively. PC1, LPT1, LPT2, L
Five I / Os consisting of PT3, COM1, and COM2
Ports are provided, and various printers are connected to the LPT1.

The printer drivers 25 and 27 are connected to the OS 10
Is connected to a spooler 29 which is configured as a part of a spool. A dummy spool 33 is also connected to the spooler 29 via a dummy device driver 31. Further, the spooler 29, the scanner driver 21, and the scanner driver 2
Numeral 3 is configured to be selectively connectable to a virtual device driver (VxD) 35 for a parallel port connected to the LPT 1.

When the scanner driver 23 receives image data and the like from the printer 7 using the LPT 1, the printer drivers 25 and 27 cannot transmit data via the LPT 1 (see the dotted line in FIG. 2). ). The dummy spool 33 temporarily stores data transmitted from the spooler 29 in such a case.

Next, the processing of the virtual device driver 35, which is a main part of the present invention, and the scanner driver 23 as its higher-level device will be described. Scanner driver 23
Receives the image data captured by the scanner function of the printer 7 through the LPT 1 and the virtual device driver 35 when a scan command is output from the image input application 11. This type of image data has a relatively large capacity and requires a great deal of time when received according to a commonly used standard protocol. Therefore, the virtual device driver 35 supports a unique non-standard protocol capable of speeding up the reception of the image data, and receives the image data by the following processing by the scanner driver 23.

FIG. 3 is a flowchart showing the processing executed by the scanner driver 23. The scanner driver 23 starts this processing when a scan command is output from the image input application 11. FIG.
As shown in (1), when the process is started, an ID request is transmitted to the virtual device driver 35 in S1 (S represents a step: the same applies hereinafter). Here, the ID is identification information indicating that the virtual device driver 35 supports the non-standard protocol, and is represented by, for example, a character string including a trademark or the like of a maker that provides the scanner driver 23. The scanner driver 23 and the virtual device driver 35 are usually provided from the maker of the printer 7 attached to the printer 7. When the printer 7 is connected to the personal computer 1, the user installs the scanner driver 23 and the virtual device driver 35 on the personal computer 1. Install. If the virtual device driver 35 is attached together with the scanner driver 23 in advance, a unique ID is returned to the scanner driver 23 by a process described below in response to the ID request in S1.

The process of the scanner driver 23 proceeds to S3 following S1, and performs ID reception processing. Subsequently, the received ID is the unique ID (S5), or another I
D or (S7) is sequentially determined. Virtual device driver 3
If the ID has not yet been returned from step 5, a negative determination is made in both steps S5 and S7, and the process proceeds to step S9. In S9, it is determined whether or not a predetermined time has elapsed and a timeout has occurred. If the timeout has not occurred (S9: NO), the process proceeds to S9.
3 and after performing the ID receiving process again, S5 to S9
Execute the judgment.

During execution of the loop processing of S3 to S9,
When the unique ID is received from the virtual device driver 35 (S5: YES), the process proceeds to S11 to determine whether the system supports the non-standard protocol.
This determination is also made by data communication with the virtual device driver 35, as described later. If the system supports it (S11: YES), S1
Then, the process proceeds to 3 and the reception of the image data according to the non-standard protocol is instructed, and the process is temporarily terminated.

It should be noted that, even if an instruction to receive a non-standard protocol is issued in S13, this instruction is immediately transmitted to the virtual device driver 35, and the image data scanned by the printer 7 is not necessarily received. That is, in response to a scan command from the image input application 11, the scanner driver 23 transmits the J
A reception instruction is output in OB units. At that time, the instruction of the protocol is transmitted to the virtual device driver 35.

On the other hand, when the ID is received from the virtual device driver 35 during the execution of the loop processing of S3 to S9, but the ID is another ID different from the unique ID (S7: YES). , To S15, instruct the virtual device driver 35 to receive the image data according to the standard protocol, and once terminate the process. Also, S3
If the timeout occurs without receiving the ID from the virtual device driver 35 during the execution of the loop processing of S9 to S9 (S9: YES), the same applies to S15.
Then, the reception is instructed by the standard protocol, and the process is temporarily terminated. Note that when the processing of S15 is executed,
Similarly to 13, the instruction is transmitted to the virtual device driver 35 when the reception instruction is output.

Here, after installing the scanner driver 23 together with the corresponding virtual device driver 35,
When another scanner driver 21 is installed together with the corresponding virtual device driver 35, the virtual device driver 35 is replaced with the one corresponding to the scanner driver 25 installed later. That is, although a plurality of scanner drivers 21 and 23 can be installed in the personal computer 1, usually only one virtual device driver 35 can be installed. For this reason,
When a new scanner driver and virtual device driver 35 are installed in the personal computer 1, the virtual device driver 35 that has already been used cannot be used.

In such a case, another ID is returned from the virtual device driver 35, or the virtual device driver 35 does not recognize the ID request and does not respond at all. Therefore, in such a case, a positive determination is made in S7 or S9, and the process shifts to S15 to instruct reception using a standard protocol supported by almost all general virtual device drivers. It should be noted that even if the reception is instructed by the standard protocol in S15, if the virtual device driver 35 is controlled by a completely different code system, it cannot be recognized even if this instruction is given. However, also in this case, the virtual device driver 35 determines that there is no instruction at all, and receives the image data according to the standard protocol as usual.

Further, even if the unique ID is received from the virtual device driver 35 (S5: YES), and it is determined that the virtual device driver 35 supports the non-standard protocol, the non-standard If the system does not support the protocol, for example, LPT1
Is not bidirectionally possible (S11: NO),
At S15, reception by the standard protocol is instructed.

The virtual device driver 35 supporting the above non-standard protocol has the same input / output functions as the standard virtual device driver (eg, WriteFile function, ReadFile function, and DeviceIoCo).
control function), and can be easily replaced with a standard virtual device driver for use. Next, FIG. 4 is a flowchart showing the processing executed by the virtual device driver 35. Note that the virtual device driver 35 starts this processing upon receiving any data from the scanner driver 23.

As shown in FIG. 4, when the processing is started, the virtual device driver 35 checks the control code of the received data (S21). Then, the following processing is executed according to the content of the control code. That is, if the received data is the ID request transmitted in S1 described above, the unique ID is returned in S23, and the process ends. If the received data is the system support check transmitted in accordance with S11 described above, the system is checked in S25, the result is returned to the scanner driver 23, and the process ends. Based on the returned data, the above-described S1
The decision at 1 is made.

If the received data is the above-mentioned reception instruction, the flow shifts to S27, and the image data scanned from the printer 7 by the protocol specified in S13 or S15 is received. As described above, usually, the scanner driver 23 and the virtual device driver 35 correspond to each other. In S27, the image data is received according to the non-standard protocol. However, when the system does not support the non-standard protocol, or when (S11) : NO), if the versions of the scanner driver 23 and the virtual device driver 35 are different, and if another ID (YES) is determined in S7, the image data is received by the standard protocol in S27.

Further, if it is determined in S21 that the control code of the data received from the scanner driver 23 is not any of the above, processing corresponding to the code is performed by other processing (not shown). Further, when the virtual device driver 35 is replaced with one provided by another maker, the virtual device driver 35 does not execute even processing similar to that of FIG. In this case, S
At 9 a time-out (YES) occurs and an instruction to receive data using the standard protocol is issued (S15), and the image data is received using the standard protocol in response to the receiving instruction.

FIG. 5 is a sequence diagram showing a state of data communication performed between the scanner driver 23 and the virtual device driver 35 when the above processing is executed. As shown in FIG. 5, when the scanner driver 23 transmits an ID request to the virtual device driver 35 (S1),
The virtual device driver 35 returns the ID (S2
3). Based on the ID, the scanner driver 23 selects a protocol (S5 to S11), and transmits a reception instruction in a non-standard protocol or a standard protocol to the virtual device driver 35. Then, the virtual device driver 35 receives the image data scanned from the printer 7 according to the instructed protocol, and transmits the image data to the scanner driver 23 (S27).

As described above, in the present system, when the virtual device driver 35 supports a non-standard protocol, data communication using the non-standard protocol is performed, and the virtual device driver 35 supports the non-standard protocol. When there is no data communication, data communication according to the standard protocol can be executed. Therefore,
It is possible to increase the speed of data communication and satisfactorily suppress stagnation of processing and occurrence of malfunction due to occurrence of an error.

Further, in the above system, the virtual device driver 35 transmits an ID request to the virtual device driver 35, and returns the unique ID indicating that the non-standard protocol is supported. It is determined that the above non-standard protocol is supported. For this reason, it can be determined very reliably whether or not the virtual device driver 35 supports the non-standard protocol.

That is, as a form of the processing for making this determination, various forms other than the above-described forms are conceivable. For example, it is also possible to transmit some control code from the scanner driver 23 to the virtual device driver 35 using the non-standard protocol, and if no error occurs, determine that the virtual device driver 35 supports the non-standard protocol. . However, in this case, if the virtual device driver 35 supports another non-standard protocol and the control code coincides with the control code used in the other non-standard protocol, accurate determination is difficult. Becomes

On the other hand, in the above system, it is determined whether or not the virtual device driver 35 supports the non-standard protocol according to whether or not the virtual device driver 35 returns the ID. I have. For this reason, in the above system, the above determination can be performed more accurately, and further, data communication by the non-standard protocol is performed via the virtual device driver 35 which does not support the non-standard protocol. Can be prevented more reliably. Therefore, stagnation of processing and occurrence of malfunction due to occurrence of an error can be more favorably suppressed.

Also, in the above system, I
Although D is used, various other information can be used as identification information. For example, a list of control codes for performing communication using a non-standard protocol, address data (pointer) indicating the location of a function for performing communication using a non-standard protocol, etc.
The same operation and effect can be obtained even when used in place of D.
However, when an ID represented by a character string including a trademark or the like is used, it is effective to determine that the virtual device driver 35 provided by another manufacturer does not support the non-standard protocol.

Further, in the above system, when the virtual device driver 35 determines that the non-standard protocol is not supported (S7, S9: YES), the system actively instructs reception of image data according to the standard protocol. (S15). Therefore, when the virtual device driver 35 does not support the non-standard protocol, it is possible to more reliably instruct to receive image data using the standard protocol supported by the virtual device driver 35. Therefore, stagnation of processing and occurrence of malfunction due to occurrence of an error can be more favorably suppressed.

As described above, the virtual device driver 35
Is provided by another manufacturer, etc.
When controlled by a completely different code system, the virtual device driver 35 cannot recognize this instruction. However, also in this case, the virtual device driver 35 determines that there is no instruction at all, and receives the image data according to the standard protocol as usual. Therefore, S15
Even if there is no instruction of the standard protocol in the above, tentative control is possible.

However, when the various virtual device drivers 35 are controlled by a similar code system, it is possible to reliably receive data by the standard protocol by giving the above instruction. That is, the above-described control is advantageous. However, if there is a high possibility that the various virtual device drivers 35 are controlled by completely different code systems, omitting the above-mentioned instructions prevents the instructions from accidentally matching with the control codes of other non-standard protocols. can do. That is, in this case, omitting the above instruction may be advantageous in preventing the scanner or the personal computer from malfunctioning. Therefore, the process may be terminated via S15 as described above when the determination is affirmative in S7, and the process may be terminated as it is when determined in S9.

The scanner driver 23 and the virtual device driver 35 may be attached to the printer 7 in the form of a floppy disk or CD-ROM, or may be a storage device such as a hard disk device of the personal computer 1 via a communication line such as the Internet. (Not shown). In the former case, floppy disk or CD-RO
In the case where M is the latter, the file server storing the driver program corresponds to the storage medium according to the third, fourth, or fifth aspect, respectively. In the above embodiment, S
1 to the identification information requesting process, S5 to the notification determining process, S1 to S9 to the determining process, S13 and S13.
The 15 processes correspond to the communication system instruction process.
Further, a storage device such as the hard disk device of the personal computer 1 storing the computer program of the determination process or the communication method instruction process, and a CPU that loads the program from the storage device to the RAM as needed and executes the program, It corresponds to the determination means or the communication method instruction means, respectively.

Further, the present invention is not limited to the above-described embodiment at all, and can be implemented in various forms without departing from the gist of the present invention. For example, in the above embodiment, when the virtual device driver 35 determines that the non-standard protocol is not supported (S7,
(S9: YES), the instruction to receive image data according to the standard protocol is issued (S15), but this instruction may not be necessary as described above. Further, in the above embodiment, the virtual device driver 35 is taken as an example of the device driver, and the printer 7 having a scanner function is taken as an example of the external device. Various forms are also conceivable. That is, the present invention can be applied to various fields in which data communication is performed with an external device via a device driver and an I / O port. For example, as an external device, in addition to a printer with a scanner, the present invention can be applied not only to a scanner function and a printer function but also to a multifunctional peripheral device having other functions (such as a communication function such as a facsimile). In this case, as the upper device of the device driver, various devices other than the scanner driver can be considered. For example, a higher-level device for transmitting data is also conceivable.

Further, in each of the above embodiments, the speed of data communication can be increased by switching between a standard communication system using a standard protocol and a non-standard communication system using a non-standard protocol. Although the stagnation of processing and the occurrence of malfunction due to the occurrence of errors are suppressed,
Other elements related to communication other than the protocol may be changed to switch between the standard communication method and the non-standard communication method.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an entire configuration of a system to which the present invention is applied.

FIG. 2 is an explanatory diagram showing a hierarchical structure of software in a personal computer of the system.

FIG. 3 is a flowchart illustrating a process of a scanner driver of the personal computer.

FIG. 4 is a flowchart showing processing of a virtual device driver of the personal computer.

FIG. 5 is a sequence diagram showing a state of data communication by the above processing.

[Explanation of symbols]

1. Personal computer 7. Printer 10. O
S11: Application for image input 12: Application for printing 21, 23: Scanner driver 25, 2
7 Printer driver 29 Spooler 33 Dummy spool 35
Virtual device driver

Claims (6)

[Claims] 1. A data communication device for performing data communication with an external device via an I / O port according to a communication method supported by a device driver, wherein the device driver is configured to perform a target non-standard communication. Determining means for determining whether or not the communication method is supported; and when the determining means determines that the device driver supports the non-standard communication method, the device driver transmits the non-standard communication method to the device driver. Communication method instruction means for instructing to perform data communication with the external device by a method, when the determination means determines that the device driver does not support the non-standard communication method. The device driver is characterized in that the device driver performs data communication with the external device according to a standard communication method supported by the device driver. Data communication device. 2. A data communication method for performing data communication with an external device via an I / O port according to a communication method supported by a device driver, wherein the device driver performs a non-standard communication intended by the device driver. A determining process of determining whether the external device is supported by the non-standard communication method when the device driver determines that the device driver supports the non-standard communication method. And a communication system instruction process for instructing the device driver to perform data communication between the device driver and the device driver, and the device driver determines that the device driver does not support the non-standard communication system by the determination process. In such cases, the device driver performs data communication with the external device using the standard communication method supported by itself. A data communication method comprising: 3. A storage medium storing a computer program for performing data communication with an external device via an I / O port according to a communication method supported by a device driver, wherein the device driver has A determination process for determining whether or not the non-standard communication method is supported; and, when the device driver determines that the device driver supports the non-standard communication method, And a communication system instruction process for instructing the device driver to perform data communication with the external device according to the communication system, and the device driver supports the non-standard communication system by the determination process. If it is determined that the device driver does not perform the communication, the device driver uses the standard communication method supported by itself. A storage medium storing a computer program for performing data communication with the external device. 4. An identification information requesting process for requesting the device driver to notify the device driver of identification information indicating that the device driver supports the non-standard communication method, After the identification information request processing, a notification determination processing for determining whether or not the identification information has been notified from the device driver.If it is determined that the identification information has been notified by the notification determination processing, If the device driver determines that the non-standard communication method is supported and determines that the identification information has not been notified by the notification determination process, the device driver supports the non-standard communication method. 4. The storage medium according to claim 3, wherein the storage medium is determined not to exist. 5. When the device driver determines that the device driver does not support the non-standard communication method by the determination processing, data is exchanged with the external device according to the standard communication method supported by the device driver. The process of instructing the device driver to perform communication,
4. The communication system instruction processing according to claim 3, wherein
Or the storage medium according to 4. 6. A device driver having the same input / output function as a standard device driver supporting a standard communication method, which supports a non-standard communication method in addition to the standard communication method. A device driver having a function of notifying the higher-level device of identification information indicating that the non-standard communication method is supported, in response to a request from the device.