JPH11212879A - Data processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data processor which can secure normal communication even if abnormality occurs in a line. SOLUTION: A data processor 10 and an external input/output unit 20 are connected by a plurality of lines 30. A line abnormality detection means 11 transmits a request signal on the line to be used and a response signal is generated from a response means 21. The line abnormality detection means detects an abnormality of the line according to whether the response signal is received or not, and a line switching means 16 switches the line to be used when an abnormality occurs in the line to be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing apparatus, and more particularly to a data processing apparatus capable of securing a normal data transfer even if a line is abnormal.

[0002]

2. Description of the Related Art For example, when an image is taken in a personal computer, a scanner is sometimes connected to the personal computer. In such a case, the personal computer and the scanner are connected using a single cable capable of transmitting and receiving the control signal and the image data, and the scanner is activated by the reading instruction from the personal computer to read the original, and the read image is transmitted to the personal computer. Sending is performed.

[0003]

However, if the cable is suddenly disconnected from the device, cut or broken, or the cable connection is damaged, it becomes impossible to capture the image into the personal computer.

[0004] In view of the above problems, it is an object of the present invention to provide a data processing device capable of guaranteeing normal data transfer even if an abnormality occurs in a line.

[0005]

Therefore, a data processing apparatus according to the present invention connects a data processing apparatus and an external input / output device via a plurality of data communication lines, and includes a Line abnormality detecting means for detecting the presence or absence of an abnormality in a line used for communication, and line switching means for switching to a line different from the line in which the abnormality is detected when an abnormality is detected. I do.

One of the features of the present invention is that a data processing device and an external input / output device are connected by a plurality of lines, and an abnormality in a line to be used is detected and transmitted by transmitting a request signal. On the point. As a result, even if an abnormality occurs in one of the lines, the line is automatically switched to another line, and normal data transfer is secured.

In order to connect the data processing device and the external input / output device with a plurality of lines, the data processing device and the external input / output device need to have a plurality of ports. The number of ports may be two or more.

[0008] The data processing device refers to a device having a function of processing data, and the external input / output device refers to a device connected to the data processing device. In the case of an image forming system, all of a personal computer, a scanner, and a printer have a function of performing data processing, and in this sense, in the present invention, all of them can be treated as a data processing device. That is, when the personal computer is a data processing device, the scanner and the printer are external input / output devices. When the scanner is a data processing device, the personal computer and the printer are external input / output devices, and the printer is a data processing device. In this case, a personal computer and a scanner can be handled as external input / output devices.

When an alternative line is used, it is preferable to display it to the operator. Therefore, it is preferable that the data processing device further include a display unit that displays that another line is being used when the line to be used is abnormal.

[0010] Further, it is preferable that the abnormal line can be replaced while the alternative line is being used. For this reason, it is sufficient that each line can be independently attached to and detached from the data processing device and the external input / output device.

[0011]

According to the present invention, the data processing apparatus and the external input / output device are connected by a plurality of lines, and the presence or absence of an abnormality in a line to be used is detected. Since the line to be switched is switched, even if an error occurs in one of the lines, the line is automatically switched to another line, so that normal data transfer can be guaranteed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to specific examples shown in the drawings. FIGS. 1 to 6 show a preferred embodiment of a data communication line control apparatus according to the present invention, which is an example applied to a system for taking in an image to a personal computer using a scanner. FIG. 1 shows the overall configuration of the above system. The system comprises a personal computer 10, a scanner 20, and a plurality of lines 30 connecting the two.

The personal computer 10 includes a CPU 11 for performing various arithmetic processing, a ROM 12 for storing programs and / or data, a RAM 13, a storage device 14,
An operation unit 15 for operating the PU 11, a plurality of input / output ports 18, a selector 16 for switching the ports 18,
It comprises a display unit 17 for performing various displays.

On the other hand, a scanner 20 includes a CPU 21 for performing various arithmetic processing, a reading unit 22 for reading an image,
It comprises a ROM 23 and a RAM 24 for storing programs and / or data, a plurality of input / output ports 26, and a selector 25 for switching the ports 26.

The line 30 is connected between the plurality of input / output ports 18 of the personal computer 10 and the plurality of input / output ports 26 of the scanner 20. Each of the lines (cables) 1, 2,... Is independent, and can be detachably attached to each of the input / output ports 18, 26 independently.

FIG. 6 shows the structure of the selector 16. The selector 16 includes an input buffer memory 160, a switching circuit 161, and a plurality of output buffer memories 162... The switching circuit 161 switches the line 30, while the input buffer memory 160 receives image data and The image data at 160 is transmitted to the line 30 via the selected output buffer memory 162.

Next, a line control method will be described with reference to FIGS. FIG. 2 shows a personal computer 1
0 is a flowchart of the processing in FIG.
4 shows a screen of the display unit 17 of the personal computer 10, and FIG. 5 shows an example of a signal table in a program of the image reading application.

First, when "read" is designated on the screen of the display unit 17 of the personal computer 10, an image reading application program is started, and the selector 16 selects the first input / output port 18 to be normally used. Then, a request signal Req is transmitted to the scanner 20 via the first line 30 (step S10 in FIG. 2). Upon receiving the request signal Req sent through the first line 30, the scanner 20 generates a response signal Ack toward the line 30 (steps S20 and S2 in FIG. 3).
1).

The personal computer 10 receives the request signal Re.
After the transmission of q, if the response signal Ack is transmitted from the scanner 20 via the first line 30 to be normally used within a predetermined time, the first line 30 to be normally used is normal. Thereafter, a normal image reading operation is performed, the reading unit 22 reads an image with the scanner 20, the image data is transmitted via the first line 30, is captured by the personal computer 10, and is stored in the storage device 14. (Steps S11 and S12 in FIG. 2).

However, if no response is received even after a predetermined time has passed through the first line 30, which is to be used normally, a Req signal is transmitted via another one, for example, the second line 30. (Steps S11 and S13 in FIG. 2).

The request signal Req via another line 30
Is transmitted, and if a response signal Ack is transmitted from any one of the lines 30 from the scanner 20 within a predetermined time,
The image data is received (or transmitted) using the line 30. For example, if a response signal Ack is transmitted via the second line 30 at this time, the image data is received (or transmitted) using the second line 30. Further, when the first line 30 to be used normally becomes abnormal, when the alternative line 30 to be used is selected, a line monitor display appears on the screen of the display unit 17 of the personal computer 10, and “ Line 1: Unavailable (needs investigation), Line 2: Busy "
Is displayed (steps S13 and S13 in FIG. 2).
14 and step S15).

As described above, the line (cable) in which the abnormality is detected is displayed, so that the user can immediately exchange the line with a new line. This line cable replacement
It can also be performed during data communication using another line, and can wait for the next use. Although the processing in the case where the line cable is exchanged is not described in the flowchart of the above embodiment, it is preferable that the abnormal display of the line is erased when the exchange is performed. .

Further, even if a predetermined time has passed, the request signal Req
If there is no response via the line 30 that has transmitted the request signal, a series of operations of sending a request signal Req to the scanner 20 via a line not sending the request signal Req and waiting for a response is repeated (FIG. 2). Steps S13, S14, S15 and S16).

Lastly, even if the request signal Req is transmitted through all the lines 30 and there is no response from any of the lines 30, the line monitor display on the screen of the display unit 17 of the personal computer 10 displays "all lines". "Fail on line" is displayed (step S17 in FIG. 2).

FIG. 5 shows an example of a signal table in an image reading application program. in this case,
First, the scanner 2 is connected via the first line 30 to be normally used.
0, the response signal Aq is not returned from the scanner 20. Therefore, the request signal Req is transmitted through the second line 30, and the response signal A is transmitted from the second line 30.
Since the ck is returned, image data is received (or transmitted) via the second line 30.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a preferred embodiment of a data transfer line controller according to the present invention.

FIG. 2 is a flowchart showing processing of the personal computer in the embodiment.

FIG. 3 is a flowchart illustrating processing of a scanner according to the embodiment.

FIG. 4 is a diagram illustrating an example of a screen of a display unit of the personal computer in the embodiment.

FIG. 5 is a diagram showing an example of a signal table in a program of an image reading application in the personal computer.

FIG. 6 is a configuration diagram showing a selector in the personal computer.

[Explanation of symbols]

 Reference Signs List 10 personal computer (data processing device) 11 CPU (line abnormality detection means) 16 selector (line switching means) 17 display unit (display means) 20 scanner (external input / output device) 21 CPU (response means) 30 lines

Claims (3)

[Claims] 1. A line abnormality detector for connecting a data processing device and an external input / output device by a plurality of data communication lines and detecting whether or not there is an abnormality in a line used for data communication among the plurality of data communication lines. A data processing device, comprising: a unit; and a line switching unit that, when an abnormality is detected, switches to a line different from the line in which the abnormality is detected. 2. The data processing apparatus according to claim 1, further comprising display means for displaying that said another line is being used. 3. The system according to claim 1, wherein each of the plurality of lines is detachable from a data processing device and an external input / output device.
Or the data processing device according to 2.