JPH11102329A - Electronic device and its control method, and memory medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the use of another interface from being disturbed when one interface is abnormal. SOLUTION: In a step S301, it is judged whether or not respective interfaces are normal namely, whether a communication can be made normally through the respective interfaces. If there is an abnormal interface, only normal interfaces are made ready for reception in a step S305 to inhibit reception from being performed by the abnormal interface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device, a control method thereof, and a memory medium, and more particularly to an electronic device having a plurality of interface means for connecting to an external device, a control method thereof, and a memory medium.

[0002]

2. Description of the Related Art There are various types of image processing apparatuses such as printers for exchanging data with an external device for a computer via an interface device. Generally, image processing apparatuses are broadly classified into those having only one interface device and those having a plurality of interface devices. The former image processing device can be connected only to an external device having the same type of interface device, and thus has a problem in terms of system expansion and change.
On the other hand, the latter image processing apparatus has an advantage that the system can be easily constructed because it can be connected to an external device having various types of interface devices.

Further, image processing apparatuses having a plurality of interface devices are roughly classified into the following two types. One is an image processing device that includes a dedicated hardware wafer such as a controller and a memory for each interface device, and can simultaneously communicate with a plurality of external devices via each interface device. Such an image processing apparatus has a problem that the cost increases because dedicated hardware is required for each interface. The other is an image processing device in which a plurality of interface devices share a hardware wafer such as a controller and a memory. In such an image processing device, data is communicated using one interface device. Has a feature that communication by another interface device cannot be performed.

Image processing apparatuses of the type in which hardware is shared by a plurality of interface apparatuses are further roughly classified into the following two types. One is an image processing apparatus that fixedly sets available interface devices in advance. The other is an image processing apparatus that automatically switches an interface device to be used in response to a data reception request.

Hereinafter, an image processing apparatus that automatically switches an interface device to be used in response to a data reception request will be described.

FIG. 1 is a block diagram showing the configuration of an ink jet printer as an example of an image processing apparatus. The CPU 101 performs generation of bitmap data, analysis of commands, various settings according to input from the operation unit 109, and the like. A control program to be provided to the CPU 101 is stored in the ROM 102. RAM 103 is
It functions as a work memory of the CPU 101 and is used for generating bitmap data and the like. The first and second interface units 104a and 104b exchange data with the computers 120 and 130, respectively. Here, as an example of an image processing apparatus having a plurality of interface units, two interface units 10
4 and 104b.

[0007] The EEPROM 105 holds settings such as the type of font and the type of printing paper. The motor controller 106 includes a controller for a carriage motor for scanning a carriage unit having a print head mounted thereon in the main scanning direction, and a controller for a line feed motor for feeding printing paper in the sub-scanning direction every one or more main scans. Having. The print head controller 107 transfers bitmap data to the print head, and also performs control related to ink ejection. The CGROM 108 stores character patterns in Japanese and / or foreign languages (for example, English). The operation unit 109 is used by a user to input various setting information and to display the state of the image processing apparatus 100 and the like.

FIG. 2 is a flowchart for explaining the operation of the conventional image processing apparatus. In this conventional example, the states of the image processing apparatus 100 are classified into 1) an interface use state and 2) an all interface use state. In this specification, the interface use state refers to a state in which one of all interface units (here, 104a and 104b) is used. In addition, the all-interface usable state refers to a state in which none of the interface units are used and data reception can be started by any of the interface units.

When the processing shown in the flowchart of FIG. 2 is started (for example, when the power is turned on), first, in step S2
01, all the interface units 104a and 10a
4b is set to a receivable state (a state where all interfaces are usable). Next, in step S202, a reception request from each of the computers 120 and 130 is monitored, and if a reception request occurs, the process proceeds to step S203. Steps S201 and S202 are processes in a state where all interfaces can be used.

In step S203, reception by an interface unit other than the interface unit relating to the reception request is prohibited, and the start of reception by the interface unit relating to the reception request is permitted. For example, if the interface unit that has detected the reception request in step S202 is the first interface 104a, step S203
Then, the reception by the second interface 104b is prohibited.

In step S204, it is determined whether the interface unit related to the reception request is the same as the interface unit used in the previous reception processing. If the interface unit is the same, the process proceeds to step S205. move on. For example, if the interface unit related to the reception request is the first interface unit 104a and the interface unit used in the previous reception processing is the interface 104a, the determination result in step S204 is “yes”. Immediately after the activation of the image processing apparatus 100, that is, before executing the reception processing, the interface unit and related settings have default setting values.

In step S206, a process of switching the interface unit to be used from the interface unit used in the previous reception process to the interface unit related to the reception request is performed (interface switching process).
The interface switching process discharges the print sheet after completing the printing process based on the received data related to the previous receiving process, and deletes unnecessary receiving data from the receiving buffer (for example, provided in the RAM 103). Then, for example, various settings such as a printing method and printing paper are changed to initial values or settings according to the interface unit related to the reception request.

On the other hand, if the interface unit related to the reception request is the same as the interface unit used in the previous reception process, the interface switching process in step S206 is not executed.

In step S205, step S202
Analyzing the data received via the interface unit which has detected the reception request, and executes the printing process based on the analysis result.

In step S207, it is determined whether or not subsequent reception data exists in the reception buffer. If reception data exists, the process returns to step S205, and if no reception data exists, the process proceeds to step S208.

In step S208, the time is measured by a timer for judging timeout, and the time is measured.
If the subsequent data is not received even after elapse of (0 seconds), the process returns to step S201. On the other hand, if the subsequent data is received before the specified time has elapsed, step S2 is performed.
Return to 07. Steps S203 to S208 are processing in the interface use state.

According to the above-described processing, an interface unit related to a reception request can be automatically selected from a plurality of interface units.

[0018]

However, in the above-described image processing apparatus, for example, when the power of a computer that is communicating with the image processing apparatus is turned off, the signal level constituting the interface cable is reduced. Is unstable, the corresponding interface unit may be regarded as being in a communication state. in this case,
Since the use of all other interfaces remains prohibited, the printing operation is interrupted for a long time.

The above-mentioned problem is the same not only in the image processing apparatus but also in general electronic equipment.

The present invention has been made in view of the above background, and has as its object to improve the efficiency of communication with a plurality of external devices.

[0021]

An electronic apparatus according to the present invention is an electronic apparatus having a plurality of interface means for connecting to an external device, and determines whether communication by each interface means can be performed normally. And a control unit that enables communication by an interface unit related to a communication request among interface units that can perform normal communication.

In the above electronic device, the control means may be a communication restriction means for prohibiting communication by an interface means which cannot perform normal communication, and a control means for controlling a communication request among the interface means capable of performing normal communication. It is preferable to have an interface management means for permitting communication by the interface means and prohibiting communication by interface means other than the interface means for permitting the communication.

In the above electronic apparatus, the interface management means may start communication with an external device via one interface means, and thereafter, when no data is exchanged for more than a predetermined time, the communication by the interface means is stopped. It is preferable that the prohibition of the communication by the other interface means is canceled assuming that the communication has been completed.

[0024] In the above electronic apparatus, the determination means may re-transmit the communication by each interface means after a lapse of a predetermined time since the communication restriction means prohibits the communication by the interface means which cannot perform normal communication. It is preferable to determine whether or not can be performed normally.

In the above electronic device, it is preferable that, when the interface means relating to the communication request is changed, the interface managing means switches the interface means permitting the communication in accordance with the change.

In the above electronic device, the interface management means compares the interface means relating to the previous communication with the interface means relating to the new communication request. After the processing is completed, it is preferable to permit communication by the interface means for the new communication request.

The electronic device may further include image forming means for forming an output image based on data received through any of the plurality of interface means.

In the above electronic apparatus, at least one of the plurality of interface means may be an interface means conforming to Centronics.

In the above electronic equipment, at least one of the plurality of interface means may be a serial interface means.

In the above electronic apparatus, at least one of the plurality of interface units may be an IrDA interface unit.

In the above electronic device, the determination means determines whether or not communication by the interface means can be normally performed based on the level of a Strobe signal line connected to the interface means conforming to Centronics. Can be.

A method for controlling an electronic device according to the present invention is a method for controlling an electronic device having a plurality of interface means for connecting to an external device, and determines whether communication by each interface means can be performed normally. And a control step of enabling communication by an interface unit related to a communication request among interface units capable of performing normal communication.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. FIG. 1 is a block diagram illustrating a configuration of an image processing apparatus according to a preferred embodiment of the present invention. The details of the hardware configuration of the image processing apparatus are as described above.

The image processing apparatus according to this embodiment includes first and second interface units 104a and 104b as a plurality of interface units. These interface units may be, for example, a Centronics-compliant interface unit, a serial interface unit, an IrDA interface unit, or another interface unit. In addition, these interface units
In this embodiment, the first interface unit 104a will be described as a Centronics-compliant interface unit.

FIG. 4 is a diagram showing a group of signal lines constituting an interface conforming to Centronics. One of the signal lines is a Strobe signal line which is a signal line driven by a computer (host) as a signal line for controlling data transfer. This Strobe signal is
Used together with the Busy signal, active at the timing when data is output from the computer (LOW level)
Transitions to. In synchronization with the Strobe signal, the image processing apparatus 100 on the receiving side transitions the Busy signal to active (HIGH level). Then, when the reception of one data is completed and the subsequent data can be received, the image processing apparatus 100 changes the Busy signal to inactive (LOW level).

Some computers having an interface unit conforming to Centronics make the state of the signal lines constituting the interface cable unstable when the power is shut off. For example, Str that should be at the HIGH level without transferring data
One example is a computer in which the ob signal goes low when the power is turned off. When such a computer is connected to the image processing apparatus 100, the corresponding interface unit is recognized as being in use by turning off the power of the computer. The use of the part will be prohibited. In order to eliminate this state, it is necessary to turn on the power of the computer and to disconnect the interface cable from the computer. Such an operation significantly reduces the efficiency of printing.

The image processing apparatus according to this embodiment solves the above-described problem by prohibiting the use of an interface unit that cannot perform normal communication.

In this embodiment, a case where the Strobe signal is unstable is taken as an example of a case where there is an abnormality in the interface. However, various modes are conceivable as the specifications of the interface and the contents of the abnormality. Is not to be construed as limiting the technical scope of the present invention.

FIG. 3 is a flowchart showing the operation of the image processing apparatus according to the present embodiment. The processing shown in this flowchart is performed by the CPU 101 based on the control program stored in the ROM 102. Here, the memory medium storing this control program is RO
The control program is not limited to M and can be constituted by, for example, an FD, a CD-ROM, or the like.

The states of the image processing apparatus 100 according to the present embodiment are classified into 1) interface use state, 2) all interface use state, and 3) normal interface use state. In this specification,
The interface use state refers to a state in which one of all interface units (here, 104a and 104b) is used. Also,
The all-interface-enabled state refers to a state in which none of the interface units are used and data reception can be started by any of the interface units. The normal interface usable state refers to a state in which no interface unit is used, and data reception can be started only by the normal interface unit.

When the process shown in the flowchart of FIG. 3 is started (for example, when the power is turned on), first, in step S3
01, all the interface units 104a and 10a
It is checked whether 4b is normal, that is, whether reception is normally possible by any of the interface units. Various methods can be adopted as a check method.For example, regarding all the interface units, dummy data and the like are sequentially transferred to and from a connected computer, and the interface unit that has successfully transferred the dummy data is sequentially transferred. A method that is regarded as a normal interface unit is preferable. For example, the Strobe signal line of the interface cable connected to the first interface unit 104a (the Centronics-compliant interface unit)
When the level is at the W level, dummy data cannot be transferred, so that the interface unit can be determined to be an abnormal interface unit. Also, for example, S
An abnormal interface unit may be specified by detecting the level of a control signal line such as a torbe signal line.

In step S302, step S301
, It is determined whether there is an abnormal interface unit, that is, an interface unit that cannot normally communicate data with the connected computer. If it is determined that an abnormal interface exists, the process proceeds to step S305. If it is determined that all the interfaces are normal, the process proceeds to step S303.

In step S303, all the interface units 104a and 104b are set in a receivable state (all interface usable states). Then, step S
In step 304, reception requests from the computers 120 and 130 are monitored, and if a reception request occurs, step S30 is performed.
Proceed to 8. Steps S303 and S304 are operations in a state where all interfaces can be used.

On the other hand, in step S305, the use (reception) of the abnormal interface is prohibited, and only the normal interface can be received. Step S306
In S307, the time is measured by a timer for timeout determination, and if a reception request is not generated even after a specified time (for example, 10 seconds) has elapsed ("yes" in S306).
In step s "), the process returns to step S301. On the other hand, if a reception request is generated via the normal interface unit within the specified time, the process proceeds to step S308. In steps S305 to S307, the normal interface can be used. This is the process in the state.

In step S308, reception by the interface unit other than the interface unit related to the reception request is prohibited, and reception by the interface unit related to the reception request is started.

In step S309, it is determined whether the interface unit related to the reception request is the same as the interface unit used in the previous reception processing. If the interface unit is the same, the process proceeds to step S310. It proceeds to S313. Immediately after the activation of the image processing apparatus 100, that is, before executing the reception processing, the interface unit and related settings have default setting values.

In step S313, a process of switching the interface unit to be used from the interface unit used in the previous reception process to the interface unit related to the reception request is performed (interface switching process).
The interface switching process discharges the print sheet after completing the printing process based on the received data related to the previous receiving process, and deletes unnecessary receiving data from the receiving buffer (for example, provided in the RAM 103). Then, for example, various settings of the printing method and printing paper are changed to initial values or settings according to the interface unit related to the reception request.

On the other hand, if the interface unit related to the reception request is the same as the interface unit used in the previous reception process, the interface switching process in step S309 is not executed.

In step S310, step S304
Alternatively, in step S307, data received via the interface unit that has detected the reception request is analyzed, and print processing is executed based on the analysis result.

In step S311, it is determined whether or not subsequent reception data exists in the reception buffer. If reception data exists, the process returns to step S310. If no reception data exists, the process proceeds to step S312.

In step S312, the time is measured by a timer for time-out determination, and the time is measured for a specified time (for example, 1).
If the subsequent data is not received even after the elapse of (0 seconds), the process returns to step S301. If the subsequent data is received before the specified time has elapsed, the process returns to step S311.

With the above processing, the interface unit related to the reception request can be automatically selected from the plurality of interface units, and if an abnormal interface exists or occurs, the abnormal interface unit By prohibiting the use, it is possible to prevent the use of other normal interface units from being hindered.

The above description relates to an image processing apparatus that switches an interface unit to be used in response to a reception request from a computer. However, the present invention is also applicable to a case where an image processing apparatus issues a reception request to a computer. Can be. That is, it can be said that the present invention can be applied to an apparatus that switches the interface unit according to a communication request.

Although the above description relates to an image processing apparatus represented by, for example, an ink jet printer, the present invention can be similarly applied to other types of image processing apparatuses. In addition, the present invention can be widely applied to general electronic devices including computers and other information processing devices in addition to image processing devices.

The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), and can be applied to a single device (for example, a copier, a facsimile). Device).

Another object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to provide a computer (or CPU) of the system or apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0061]

According to the present invention, communication with a plurality of external devices can be made more efficient.

[0062]

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to a preferred embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of an image processing apparatus according to a conventional example.

FIG. 3 is a flowchart showing an operation of the image processing apparatus according to the preferred embodiment of the present invention.

FIG. 4 is a diagram showing signal lines constituting an interface conforming to Centronics.

Claims (23)

[Claims] 1. An electronic apparatus having a plurality of interface means for connecting to an external device, comprising: a determination means for determining whether communication by each interface means can be performed normally; An electronic device, comprising: a control unit that enables communication by an interface unit related to a communication request among interface units that can be performed. 2. The communication device according to claim 1, wherein the control unit prohibits communication by an interface unit that cannot perform normal communication, and a communication unit that performs a communication request among the interface units that can perform normal communication. 2. The electronic device according to claim 1, further comprising: an interface management unit that permits communication by an interface unit other than the interface unit that permits the communication. 3. The interface management means, wherein, after starting communication with an external device via one interface means, if there is no data exchange for more than a predetermined time, the communication by the interface means is terminated. 3. The electronic apparatus according to claim 2, wherein the prohibition of communication by another interface means is released. 4. The communication device according to claim 1, wherein the determination unit includes:
After a lapse of a predetermined time from prohibiting communication by the interface means that cannot perform normal communication,
3. The electronic device according to claim 2, wherein it is determined whether communication by each interface unit can be normally performed. 5. The communication device according to claim 1, wherein the interface management unit is configured to:
3. The electronic device according to claim 2, wherein the interface means for permitting communication is switched according to the change. 6. The interface management means compares the interface means related to the previous communication with the interface means related to the new communication request, and when the two are different, ends the processing of the data related to the previous communication. later,
3. The electronic device according to claim 2, wherein communication by an interface unit relating to a new communication request is permitted. 7. The image processing apparatus according to claim 1, further comprising an image forming unit that forms an output image based on data received through any of the plurality of interface units. An electronic device according to claim 1. 8. The electronic device according to claim 7, wherein at least one of the plurality of interface units is a Centronics-compliant interface unit. 9. The electronic apparatus according to claim 7, wherein at least one of the plurality of interface units is a serial interface unit. 10. The method according to claim 10, wherein at least one of the plurality of interface means is IrDA.
8. An interface means, comprising:
An electronic device according to claim 1. 11. The apparatus according to claim 1, wherein the determination unit determines, based on the level of a Strobe signal line connected to the Centronics-compliant interface unit, whether communication by the interface unit can be performed normally. 9. The electronic device according to 8. 12. A method for controlling an electronic device having a plurality of interface means for connecting to an external device, comprising: a determination step of determining whether communication by each interface means can be performed normally; A control step of enabling communication by an interface unit related to a communication request among interface units that can be performed, and a control method of an electronic device. 13. The control step includes a communication restriction step of prohibiting communication by an interface unit that cannot perform normal communication, and a communication by an interface unit related to a communication request among the interface units that can perform normal communication. The method according to claim 12, further comprising: an interface management step of permitting communication by an interface unit other than the interface unit that permits the communication. 14. The interface management step,
When communication with an external device is started via one interface unit and data exchange is stopped for a predetermined time, it is considered that communication by the interface unit has been completed and communication by another interface unit is completed. The control method for an electronic device according to claim 13, wherein the prohibition of the electronic device is released. 15. The communication method according to claim 15, wherein in the communication restriction step, after a predetermined time has elapsed from prohibiting communication by an interface unit that cannot perform normal communication, communication by each interface unit can be performed normally again. The method of controlling an electronic device according to claim 13, wherein it is determined whether or not the electronic device is operating. 16. In the interface management step,
14. The control method for an electronic device according to claim 13, wherein, when the interface unit related to the communication request is changed, the interface unit that permits the communication is switched according to the change. 17. In the interface management step,
Compare the interface means relating to the previous communication with the interface means relating to the new communication request, and if the two are different, after finishing the processing of the data relating to the previous communication, the interface means relating to the new communication request 14. The method according to claim 13, wherein communication is permitted. 18. The image processing method according to claim 12, further comprising an image forming step of forming an output image based on data received via any one of the plurality of interface units. 3. The method for controlling an electronic device according to claim 1. 19. The method according to claim 18, wherein at least one of the plurality of interface units is a Centronics-compliant interface unit. 20. The apparatus according to claim 1, wherein at least one of the plurality of interface units is a serial interface unit.
9. The method for controlling an electronic device according to item 8. 21. At least one of the plurality of interface means is IrDA
2. An interface means, comprising:
9. The method for controlling an electronic device according to item 8. 22. In the determining step, it is determined based on the level of a Strobe signal line connected to a Centronics-compliant interface means whether or not communication by the interface means can be performed normally. 20. The method for controlling an electronic device according to claim 19. 23. A memory medium storing a control program for an electronic device having a plurality of interface means for connecting to an external device, wherein a determination step of determining whether communication by each interface means can be performed normally. A memory medium, comprising: a code; and a code of a control step for enabling communication by an interface unit related to a communication request among interface units capable of performing normal communication.