JP2001022690A - Method and system for data communication between devices - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a system, especially, an initializing procedure thereof for data communication between devices by which optimal communication conditions are automatically set without changing a parameter such as a setting value in a program ROM or non-volatile RAM. SOLUTION: In an image processing system constituted by combining an image control device and one or plural image input/output devices and connecting the image input/output devices and the image control device through communication, when the image control device has a first communication control part and the image input/output device has a second communication control part, at the initialization, prescribed communication conditions are set to the first and second communication control parts S502 and S522, the communication conditions are determined on the basis of ability of communication exchanged through communication S503-S508 and S523-S526, the determined communication conditions are reset to the first and second communication parts S509 and S527 and following communication is continued S510, S511 and S528-S530.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and system for data communication between devices, and more particularly to a data communication method in an image processing system including an image input / output device and an image control device.

[0002]

2. Description of the Related Art Conventionally, in a system in which, for example, an image input / output device and an image control device are controlled by independent CPUs, communication conditions (such as a baud rate of serial communication) between the CPUs are written in, for example, a program ROM. This is set using a fixed value such as a predetermined value stored in the memory or a value written in a nonvolatile RAM.

[0003]

Therefore, in the above-mentioned conventional example, when trying to connect devices having different communication conditions, the program ROM is rewritten or the nonvolatile RAM is rewritten.
Work such as resetting the value of was required.

[0004] On the other hand, the communication speed required for the system depends on the performance of each connected device, and varies depending on, for example, the image processing speed of the input / output device. The maximum communication speed that can be obtained differs depending on the performance of the CPU and the communication control LSI mounted on the device. Therefore, when a plurality of devices having different performances are connected to one device, that is, when one controller unit is connected to input / output devices having different performances, or when one input / output device is connected to controller units having different performances. In such a case, it is necessary to determine an optimal communication condition based on the mutual communication conditions.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made in consideration of the problem described above. An apparatus for automatically setting optimum communication conditions without changing parameters such as set values of a program ROM and a nonvolatile RAM is provided. The present invention provides a data communication method and a system thereof, particularly, an initialization procedure thereof.

[0006]

In order to achieve the above object, an image processing system according to the present invention comprises: an image control device;
An image processing system configured by combining one or more image input / output devices, wherein the image input / output device and the image control device are connected by a communication unit, and the image control device is connected to the communication unit. The image input / output device has a second communication control unit connected to the communication unit, and sets a predetermined communication condition at the time of initialization to the first and second communication control units. Means, determine communication conditions based on mutual communication capabilities exchanged via the communication means, reset the determined communication conditions in the first and second communication control means, And control means for controlling to continue communication thereafter.

Here, the control means includes first control means for controlling the first communication control means in the image control device, and second control means for controlling the first communication control means in the image input / output device. And second control means for controlling The determination of the communication condition is executed by the first control means. The determination of the communication condition is executed by the second control means. In addition, the determination of the communication condition is performed by the first
And determination of the maximum capacity of each of the second communication control means to the lower one. Further, an image reading device is connected as the image input / output device and operates as an image reading system. Further, an image forming apparatus is connected as the image input / output device, and operates as an image forming system. In addition, an image reading device and an image forming device are connected as the image input / output device, and operate as an image input / output system. Further, when a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, the maximum baud rate allowed by the image input / output device and the image The smaller of the maximum baud rates allowed by the controller is determined as the baud rate.

A system according to the present invention is a system in which a plurality of devices are combined and connected by communication means. The first device has first communication control means connected to the communication means. , The second device has second communication control means connected to the communication means, and at the time of initialization, sets predetermined communication conditions in the first and second communication control means, and sets the communication means to A communication condition is determined on the basis of the mutual communication capabilities exchanged via the control unit, and the determined communication condition is set again in the first and second communication control means, and the subsequent communication is controlled to be continued. And control means. Here, a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and when the communication condition is a communication baud rate, a maximum baud rate allowed by one device,
The smaller of the maximum baud rates allowed by the other device is determined as the baud rate.

Further, a data communication method according to the present invention is constituted by combining an image control device and one or more image input / output devices, and the image input / output device and the image control device are connected by communication means. A data communication method for an image processing system, wherein the image control device has first communication control means connected to the communication means, and the image input / output device is connected to the communication means. An initial communication condition setting step of setting predetermined communication conditions in the first and second communication control means at the time of initialization, and a mutual communication capability exchanged via the communication means. And a communication condition updating step of resetting the determined communication conditions in the first and second communication control means and continuing communication thereafter. Including It is characterized in.

Here, a first control means in the image control device for controlling the first communication control means, and a second control means in the image input / output device for controlling the second communication control means. The initial communication condition setting step, wherein the first and second control means set predetermined communication conditions in the first and second communication control means, respectively, and the communication condition determining step Then, the first control means, via the first communication control means and the communication means, the communication condition of the highest capacity that the first control means and the first communication control means can tolerate, Transmitted to the second control means, and the second control means transmits the communication condition of the highest capacity allowable by the second control means and the second communication control means and transmitted from the first control means. To the lower communication capacity. The communication condition is determined as a new communication condition, and the determined communication condition is returned to the first control unit via the second communication control unit and the communication unit. 2 control means sets the determined communication condition in the second communication control means,
The first control means sets the returned communication condition in the first communication control means. A first control unit for controlling the first communication control unit in the image control device; a second control unit for controlling the second communication control unit in the image input / output device; In the initial communication condition setting step, the first and second control means set a predetermined communication condition in the first and second communication control means, respectively, and in the communication condition determination step, The second control means, via the second communication control means and the communication means, sets the communication condition of the highest capacity that the second control means and the second communication control means can tolerate in the first control. And the first control means transmits the communication condition of the highest capacity that the first control means and the first communication control means can accept, and the communication condition transmitted from the second control means. The communication conditions corresponding to the lower capability. And the determined communication condition is returned to the second control means via the second communication control means and the communication means. In the communication condition updating step, the first control means Sets the determined communication condition in the first communication control means, and the second control means sets the returned communication condition in the second communication control means. Further, after resetting the communication conditions, the communication is restarted after a predetermined time has elapsed. Further, when a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, the maximum baud rate allowed by the image input / output device and the image The smaller of the maximum baud rates allowed by the controller is determined as the baud rate.

Also, there is provided a data communication method for a system in which a plurality of devices are combined and connected by communication means,
The first device has first communication control means connected to the communication means, and the second device has second communication control means connected to the communication means. A communication condition is set in the first and second communication control means, a communication condition is determined based on a mutual communication capability exchanged via the communication means, and the determined communication condition is determined by the first and second communication control means. The second communication control means is set again, and the subsequent communication is continued. Here, when a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, the maximum baud rate allowed by one device and the other device The smaller of the maximum baud rates allowed by is determined as the baud rate.

Further, the storage medium of the present invention is constituted by combining an image control device and one or more image input / output devices, and the image input / output device and the image control device are connected by communication means. A computer-readable storage medium for storing a communication control program of the image processing system, wherein the image control device has first communication control means connected to the communication means, and the image input / output device is An initial communication condition setting step of setting a predetermined communication condition in the first and second communication control means at the time of initialization when the communication control program has a second communication control means connected to the communication means; And a communication condition determining step of determining communication conditions based on mutual communication capabilities exchanged via the communication means; and determining the determined communication conditions by the first and second communication conditions. Re-set in the communication control means,
And a communication condition updating step of continuing communication thereafter. Here, the communication control program is a program executed by a first control device for controlling the first communication control device in the image control device, and a program executed by the second communication control program in the image input / output device. And a program executed by a second control device that controls the control device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS <One Example of Configuration of System of Present Embodiment> An example of the overall configuration of an image input / output system as an image processing system according to an embodiment of the present invention will be described with reference to FIG. . The description of the present embodiment is based on an image input / output system, but the technical idea of the present invention is as follows.
In general, the present invention is applicable to those related to setting of communication conditions when a plurality of devices having different performances are connected to one device, and the present invention includes these.

In FIG. 1, a reader unit (image input device) 20
0 optically reads a document image and converts it into image data. The reader unit 200 mainly includes a scanner unit 210 having a function for reading a document, and a document feeding unit 250 having a function for conveying document sheets.

A printer unit (image output device) 300 conveys a recording sheet, prints image data thereon as a visible image, and discharges the recording sheet outside the apparatus. The printer unit 300 mainly includes a paper feed unit 31 having a plurality of types of recording paper cassettes.
0, a marking unit 320 having a function of transferring and fixing image data to recording paper, and a paper discharging unit 330 having a function of sorting, stapling and printing the printed recording paper outside the apparatus.

Controller unit (controller unit) 110
Is electrically connected to the reader unit 200 and the printer unit 300, and further connected to host computers 401 and 402 via the network 400.

The controller unit 110 includes the reader unit 20
0, the image data of the document is read, and the printer unit 300 is controlled to output the image data to recording paper to provide a copy function. A scanner function of converting image data read from the reader unit 200 into code data and transmitting the code data to a host computer via the network 400;
Converts the code data received through to image data,
And a printer function for outputting to the printer unit 300.

The operation unit 150 is connected to the controller unit 110, is constituted by a liquid crystal touch panel, and provides a user I / F for operating the image input / output system.

FIG. 2 is a sectional view showing a schematic configuration of the reader unit 200 and the printer unit 300.

(Exemplary Configuration of Reader Unit) The original feeding unit 250 of the reader unit feeds the originals one by one onto the platen glass 211 one by one in the leading order. To discharge. When the document is conveyed onto the platen glass 211, the lamp 212 is turned on, the movement of the optical unit 213 is started, and the document is exposed and scanned. The reflected light from the original at this time is reflected by a mirror 214, 215, 216 and a lens 217 into a CCD image sensor (hereinafter, referred to as CCD).
218). In this manner, the scanned image of the document is read by the CCD 218. CCD
The image data output from 218 is transferred to the controller unit 110 after undergoing predetermined processing.

(Example of Configuration of Printer Unit) Printer Unit 300
The laser driver 321 drives the laser light emitting unit 322, and causes the laser light emitting unit 322 to emit laser light according to the image data output from the controller unit 110. The laser beam is applied to the photosensitive drum 323, and a latent image corresponding to the laser beam is formed on the photosensitive drum 323. The developer is attached to the latent image portion of the photosensitive drum 323 by the developing device 324.

Then, at a timing synchronized with the start of the laser beam irradiation, a recording sheet is fed from one of the cassettes 311 and 312 and transported to the transfer section 325 to record the developer adhered to the photosensitive drum 323. Transfer to paper.
The recording paper on which the developer is loaded is conveyed to the fixing unit 326, and the developer is fixed on the recording paper by the heat and pressure of the fixing unit 326. The recording paper that has passed through the fixing unit 326 is discharged by a discharge roller 327.
The paper discharge unit 330 bundles the discharged recording papers and sorts the recording papers, and staples the sorted recording papers.

When double-sided recording is set,
After the recording paper is conveyed to the discharge roller 327, the rotation direction of the discharge roller 327 is reversed, and the flapper 328 is rotated.
To the re-feed conveyance path 329. Refeeding conveyance path 32
9 is transferred to the transfer unit 32 at the timing described above.
5 is fed.

(Example of Configuration of Controller) An example of the function of the controller 110 will be described with reference to the block diagram shown in FIG.

The main controller 111 mainly includes a CPU
112, a bus controller 113, and various I / F controller circuits (not shown).

CPU 112 and path controller 113
Controls the entire operation of the controller unit 110, and the CPU 112 reads the ROM_I /
It operates based on the program read via F115. Also, the operation of interpreting PDL (page description language) code data received from the host computer and developing it into raster image data is described in this program and processed by software. The bus controller 113 controls data transfer input / output from each I / F, and performs arbitration at the time of bus contention and controls DMA data transfer.

The DRAM 116 has a DRAM_I / F 11
7 are connected to the main controller 111 and are used as a work area for the operation of the CPU 112 and an area for storing image data.
As described later, the DRAM 116 stores an external storage device (for example, a host computer, a floppy disk, a CD, etc.)
The program may be loaded from the extension connector 124) and executed by the CPU 112.

The codec 118 converts the raster image data stored in the DRAM 116 into MH / MR / MMR.
/ JBIG and the like, and conversely, the compressed and accumulated code data is expanded to raster image data. The SRAM 119 is used as a temporary work area of the Codec 118. Codec 118 is I /
F120 and connected to the main controller
Data transfer to and from the AM 116 is controlled by the bus controller 113 and DMA-transferred.

A network controller (Network Co.)
ntorller) 121 is connected to the main controller 111 by an I / F 122, and is connected to an external network by a connector 122. The network is generally Ethernet.

An extension connector 124 for connecting an extension board and an I / O control unit 126 are connected to the general-purpose high-speed bus 125.
Are connected. As a general-purpose high-speed bus, PC
I-bus.

The I / O control unit 126 includes the reader unit 20
0, an asynchronous serial communication controller 127 for transmitting and receiving control commands to and from each CPU of the printer unit 300
Are connected to external I / F circuits 140 and 145 via an I / O bus 128.

The panel I / F 132 is connected to the LCD controller 131 and has an I / F for displaying on a liquid crystal screen on the operation unit 150 and a key input I / F 130 for inputting hard keys and touch panel keys. It is composed of

The operation unit 150 has a liquid crystal display unit, a touch panel attached on the liquid crystal display unit, and a plurality of hard keys. A signal input by a touch panel or a hard key is transmitted to the CPU 112 via the panel I / F 132 described above, and the liquid crystal display unit displays the panel I / F
This is for displaying the image data sent from the device 132. The liquid crystal display displays a function display, image data, and the like in the operation of the image forming apparatus.

The real-time clock module 133
Is for updating / saving the date and time managed in the device, and is backed up by the backup battery 134.

The connectors 142 and 147 are a synchronous serial I / F (143, 148) and a video I / F connected to the reader unit 200 and the printer unit 300, respectively.
(144, 149).

The scanner I / F 140 has a connector 142
The scanner is connected to the main controller 111 via the scanner bus 141, and the image received from the reader 200 is subjected to optimal binarization according to the contents of processing in the subsequent process. And a function of performing a magnification process of main scanning and sub scanning, and a function of outputting a control signal generated based on a video control signal transmitted from the reader unit 200 to the scanner bus 141. Have.

Data transfer from the scanner bus 141 to the DRAM 116 is controlled by the bus controller 113.

The printer I / F 145 has a connector 147
Is connected to the main controller 111 via a printer bus 146, and performs smoothing processing and the like on the image data output from the main controller 111, and
0, and also has a function of outputting a control signal generated based on the video control signal sent from the printer unit 300 to the printer bus 146.

The transfer of the raster image data developed on the DRAM 116 to the printer unit is controlled by the bus controller 113, and transferred to the printer unit 300 via the printer bus 146 and the video I / F 149.
Will be transferred.

(Detailed Description of Leader Unit) Next, a more detailed functional configuration example of the leader unit will be described with reference to the block diagram shown in FIG.

The connector 231 is connected to the controller 110
Of the CPU 142 (ie, CP
It comprises an asynchronous serial communication I / F 143 for performing command communication between the U 112 and the CPU 228), and a Video_I / F 144 for transferring a video signal.

The CPU 228 is a one-chip CPU that controls the entire scanner reader unit, and includes a timer, a DMAC,
It has functions such as a serial communication controller (SCU) 229 and general-purpose input / output ports.

The connector 225 is connected to a document feeding unit (hereinafter, DF unit) 250, and the CPU 228 requests the DF unit 250 to feed a document when performing a reading operation. The DF unit 250 controls a motor to be equipped according to the request, and executes a document feeding operation.

The CCD driver is built in or connected to the CCD 218.
It is controlled via 30. The image data input to the CCD 218 is photoelectrically converted to an electric signal. CC
The electric signal output from D218 is amplified by amplifier 221 and input to A / D converter 222. A /
The D converter 222 converts the input analog electric signal into a digital signal and outputs it. An output signal from the A / D converter 222 is input to a shading circuit 223,
Here, light distribution unevenness and CCD sensitivity unevenness are corrected.

The output from the shading circuit 223 is
In synchronization with the video control signal (HSYNC / VSYNC) that is input to the timing generator 224 and generated here,
The data is transferred to the controller unit 110 via the connector 231.

The ROM 227 is a medium for storing a control program for the scanner unit 210, and the processing of the CPU 228 is executed based on the program. R
The AM 226 is used as a work area when the CPU 228 executes a process. In addition, CPU
228 is executed by the controller unit 110
Alternatively, the RAM 226 may be loaded from a host computer or an external storage device via the controller unit 110.

<One operation example of the system of the present embodiment> Next, the communication condition determination processing between the image control device and the image input / output device in the present embodiment in the image input / output system having the above configuration will be described. Will be described.

In this example, the CPU 112 of the controller unit 110 and the CPU 228 of the reader unit 200
The procedure for determining the serial communication conditions (baud rate) at the time of initialization will be described with reference to the flowchart shown in FIG. However, the technical idea similar to that of the example of FIG. 5 is applied to the determination of the communication conditions between the printer unit and the controller unit of the present example and the determination of the communication conditions in a system in which a plurality of devices are connected via other communication. On the other hand, it is applicable. In addition, the dashed arrow between (a) and (b) of FIG.
4 shows communication between a reader unit and a controller unit.

(Operation of Reader Unit) First, a communication condition determination sequence in the reader unit 200 shown in FIG. 1 will be described with reference to a flowchart shown in FIG.

In FIG. 5A, first, when the power is turned on, the RAM and various peripheral circuits are initialized (S50).
1). Next, the serial communication controller 229 is initialized under predetermined conditions (S502). In this embodiment,
The baud rate is set to 9600 bps data, 8 bits of stop bits, and 2 bits of parity Odd.

Next, in order to inform the controller 110 that the message can be received, the RTS signal, which is a flow control signal, is set to TRUE (S503), and a message reception waiting state is set (S504).

When the 'communication negotiation start message' is received from the controller unit 110, the upper limit baud rate of the controller unit included in the message is compared with the baud rate allowable by the reader unit (S50).
5) The smaller value is determined as a new baud rate (BRf) (S506, S507). In this example, the upper limit of the controller is 38400 bps, and the upper limit of the reader is 19200 bps. Therefore,
BRf is 19200 bps.

Next, for the controller unit 110,
The BRf is transmitted together with the “communication negotiation completed” message (S508).

When the message transmission is completed, BRf is reset in the serial communication controller 229 (S50).
9) The system enters a state of waiting for a “communication restart” message from the controller unit 110 (S510).

When a 'communication resume' message is received from the controller unit 110, normal processing is started (S51).
1).

(Operation of Controller Unit) Next, the communication condition determination sequence in the controller unit 110 shown in FIG. 1 will be described with reference to the flowchart shown in FIG. 5B.

In FIG. 5B, first, when the power is turned on, the RAM and various peripheral circuits are initialized (S52).
1). Next, the serial communication controller 127 is initialized under predetermined conditions (S522). In this embodiment,
The baud rate is set to 9600 bps data, 8 bits of stop bits, and 2 bits of parity Odd.

Next, the RTS signal, which is a flow control signal for notifying the reader unit 200 that the message can be received, is set to TRUE (S523), and the reader unit enters a receivable state (the CTS signal becomes TRUE). (S524).

After confirming that the CTS signal has become TRUE, it transmits a 'communication negotiation start message' (S525). The upper limit baud rate of the controller is added as a parameter to the message. In this embodiment, the upper limit value of the controller unit is 38400 bps.
It is.

Next, a response message from the reader unit is awaited (S526), and upon receiving the 'communication negotiation completed' message, the baud rate (BRf) added as a parameter is reset to the serial communication controller 127 (S526). S527).

Next, after a wait of 100 msec is performed for resetting the communication conditions on the leader side, a 'communication resume' message is transmitted (S529), and normal processing is started (S530).

As described above, according to the present embodiment, even when the allowable serial communication baud rate differs between the controller unit and the reader unit, the ROM
It is possible to automatically perform communication at the optimum baud rate without changing the program or the set value backed up.

In the above example, the communication negotiation process (determination of the baud rate) is performed by the reader unit, but this may be performed by the controller unit. However, when many components are connected to the system, it takes time to perform the communication negotiation processing in the controller unit. Therefore, it is preferable to perform the processing on each connected component side. As described above, in the communication between the printer unit 300 and the controller unit 110, the automatic optimal setting of the communication conditions can be performed in exactly the same procedure.

Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copier, a facsimile, etc.) Device).

Further, an object of the present invention is to supply a storage medium (or a recording medium) in which a program code of software for realizing the functions of the embodiments is recorded to a system or an apparatus, and to provide the system or the apparatus with the storage medium. The computer (or CPU or MPU) reads and executes the program code stored in the storage medium,
Needless to say, this is achieved. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.
In addition, by the computer executing the readout program code, not only the functions of the above-described embodiments are realized, but also based on the instructions of the program code,
It goes without saying that an operating system (OS) running on a computer performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into the memory provided in the function expansion card inserted into the computer or the function expansion unit connected to the computer, the program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the above-described flowchart (shown in FIG. 5).

[0068]

As described above, according to the present invention,
Even if devices having different communication performances, for example, an image control device and an image input / output device are connected, a program ROM or a non-volatile R
It is possible to provide a data communication method between devices that automatically perform communication under optimum conditions without changing an AM setting value and the like, and a system therefor.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of an image input / output system according to an embodiment.

FIG. 2 is a cross-sectional view illustrating a configuration example of an image input / output system according to the present embodiment.

FIG. 3 is a block diagram illustrating a configuration example of a controller unit according to the present embodiment.

FIG. 4 is a block diagram illustrating a configuration example of a reader unit according to the present embodiment.

FIG. 5 is a flowchart illustrating an example of a processing procedure for determining a communication condition according to the embodiment;

Claims (19)

[Claims] An image processing system configured by combining an image control device and one or more image input / output devices, wherein the image input / output device and the image control device are connected by communication means, The image control device has first communication control means connected to the communication means, and the image input / output device has second communication control means connected to the communication means. A condition is set in the first and second communication control means, a communication condition is determined based on mutual communication capabilities exchanged via the communication means, and the determined communication condition is determined by the first and second communication control means. 2. An image processing system, comprising: control means for resetting the communication control means to the second communication control means and controlling to continue communication thereafter. 2. The image processing apparatus according to claim 1, wherein said control means includes: first control means for controlling said first communication control means in said image control device; and said second communication control means in said image input / output device. 2. The image processing system according to claim 1, further comprising a second control unit for controlling the image processing. 3. The image processing system according to claim 2, wherein the determination of the communication condition is executed by the first control unit. 4. The image processing system according to claim 2, wherein the determination of the communication condition is executed by the second control unit. 5. The communication method according to claim 1, wherein the determination of the communication condition is a determination of a lower maximum capacity of each of the first and second communication control means. Image processing system. 5. The image processing system according to claim 1, wherein an image reading device is connected as said image input / output device, and operates as an image reading system. 6. The image processing system according to claim 1, wherein an image forming apparatus is connected as said image input / output device, and operates as an image forming system. 7. The image processing system according to claim 1, wherein an image reading device and an image forming device are connected as said image input / output device and operate as an image input / output system. 8. When a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, a maximum baud rate allowed by the image input / output device is determined. 8. The image processing system according to claim 1, wherein a smaller one of the maximum baud rates allowed by the image control device is determined as the baud rate. 9. A system in which a plurality of devices are combined and connected by communication means, wherein the first device has first communication control means connected to the communication means, and the second device has A second communication control unit connected to the communication unit, and at the time of initialization, a predetermined communication condition is set in the first and second communication control units, and each other exchanged via the communication unit; Control means for determining a communication condition based on the communication capability, resetting the determined communication condition in the first and second communication control means, and controlling to continue the communication thereafter. A system characterized by the following. 10. When a start-stop synchronous serial communication means is used as said communication means, a serial communication controller is used as said communication control means, and said communication condition is a communication baud rate,
10. The system according to claim 9, wherein a smaller one of the maximum baud rates allowed by the other device is determined as the baud rate.
The described system. 11. An image processing system comprising a combination of an image control device and one or more image input / output devices, wherein the image input / output device and the image control device are connected by communication means. A communication method, wherein the image control device has a first communication control device connected to the communication device, and the image input / output device has a second communication control device connected to the communication device. An initial communication condition setting step of setting predetermined communication conditions in the first and second communication control means at the time of initialization; and determining communication conditions based on mutual communication capabilities exchanged via the communication means. And a communication condition updating step of resetting the determined communication conditions in the first and second communication control means and continuing communication thereafter. Shin method. 12. A first control means for controlling the first communication control means in the image control device, and a second control means for controlling the second communication control means in the image input / output device. Control means, wherein in the initial communication condition setting step, the first and second control means set predetermined communication conditions in the first and second communication control means, respectively, and in the communication condition determination step, The first control means, via the first communication control means and the communication means, sets a communication condition of the highest capacity that the first control means and the first communication control means can tolerate; 2
The second control means communicates with the communication condition of the highest capacity allowable by the second control means and the second communication control means, and the communication transmitted from the first control means. The communication condition corresponding to the lower capability is determined as a new communication condition, and the determined communication condition is determined by the first control via the second communication control means and the communication means. In the communication condition updating step, the second control means sets the determined communication condition in the second communication control means, and the first control means transmits the returned communication 12. The data communication method according to claim 11, wherein a condition is set in said first communication control means. 13. A first control means in the image control device for controlling the first communication control means, and a second control means in the image input / output device for controlling the second communication control means. Control means, wherein in the initial communication condition setting step, the first and second control means set predetermined communication conditions in the first and second communication control means, respectively, and in the communication condition determination step, The second control means, via the second communication control means and the communication means, sets a communication condition of the highest capacity that the second control means and the second communication control means can tolerate; 1
And the first control means communicates with the communication condition of the highest capacity that the first control means and the first communication control means can tolerate, and the communication transmitted from the second control means. The second communication control means and the communication means determine the communication condition corresponding to the lower capability as a new communication condition, and determine the determined communication condition via the second communication control means and the communication means. In the communication condition updating step, the first control means sets the determined communication condition in the first communication control means, and the second control means sets 12. The data communication method according to claim 11, wherein conditions are set in said second communication control means. 14. The data communication method according to claim 11, wherein the communication is restarted after a predetermined time has elapsed after resetting the communication conditions. 15. When a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, a maximum baud rate allowed by the image input / output device is determined. 15. The data communication method according to claim 11, wherein a smaller one of the maximum baud rates allowed by the image control device is determined as a baud rate. 16. A data communication method for a system in which a plurality of devices are combined and connected by communication means, wherein the first device has first communication control means connected to the communication means, When the second device has a second communication control unit connected to the communication unit, at the time of initialization, a predetermined communication condition is set in the first and second communication control units, and The communication conditions are determined based on the mutual communication capabilities exchanged with each other, the determined communication conditions are reset in the first and second communication control means, and the subsequent communication is continued. Data communication method. 17. When a start-stop synchronous serial communication unit is used as the communication unit, a serial communication controller is used as the communication control unit, and the communication condition is a communication baud rate, a maximum baud rate permitted by one of the devices,
2. The apparatus according to claim 1, wherein a smaller one of the maximum baud rates allowed by the other device is determined as the baud rate.
6. The data communication method according to 6. 18. A communication system for an image processing system comprising a combination of an image control device and one or more image input / output devices, wherein said image input / output device and said image control device are connected by communication means. A computer-readable storage medium storing a control program, wherein the image control device has first communication control means connected to the communication means, and the image input / output device is connected to the communication means. An initial communication condition setting step of setting predetermined communication conditions in the first and second communication control means at the time of initialization; Condition determining step of determining communication conditions based on mutual communication capabilities exchanged with each other, and setting the determined communication conditions in the first and second communication control means. And re-storage medium characterized by comprising a communication condition update step to continue further communication. 19. The program according to claim 19, wherein the communication control program is a program executed by a first control device for controlling the first communication control device in the image control device; 19. The storage medium according to claim 18, further comprising: a program executed by a second control device that controls the communication control device.