JP2898988B2 - Data communication device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a data communication device capable of executing at least a first communication and a second communication in parallel.

[Prior Art] Conventionally, as this type of device, for example, a facsimile device having a memory for storing image data is known.

In such a facsimile apparatus, image data is stored in a memory in advance and transmitted (memory transmission), or received image data is sequentially stored in a memory, and after completion of reception, the image data is read out from the memory and recorded. (Memory reception). In a conventional facsimile apparatus, usually, only one line is connected, and all memories are allocated to the line, so that only one operation of transmission or reception can be executed. Therefore, if a memory overflow occurs during communication, an error is terminated at that point.

Further, by connecting a plurality of communication lines to the facsimile apparatus, for example, transmission and reception can be performed in parallel.

[Problems to be Solved by the Invention] Therefore, when the above-mentioned function of memory transmission and memory reception is provided in a facsimile apparatus to which a plurality of lines can be connected, a memory may be provided corresponding to the communication line to be connected, or a transmission memory may be provided in advance. It is conceivable to provide a memory separately into a receiving memory.

However, in the case of providing a memory corresponding to the communication line, or providing a memory dedicated to transmission and a memory dedicated to reception,
If the memory in use overflows, the communication operation ends in an error even though there is free space in other memories. That is, in the above-mentioned one, there is a problem that the memory is not used effectively.

[Means and Actions for Solving the Problems] The present invention provides a data communication device capable of executing at least a first communication and a second communication in parallel, wherein the data of the first communication and the second communication A first storage area for storing the first communication data, a second storage area for storing the first communication data,
A memory having a second storage area for storing communication data and an extended storage area capable of storing the first and second communication data, and a method for storing the first communication data in the memory. Storing the first communication data in the first storage area, and determining whether or not the first communication data can be stored in the first storage area during the storage processing;
When the first communication data cannot be stored in the first storage area, a request is made to the expansion storage area to expand the storage area for the first communication data before overflowing the first storage area. A first processing unit that, when storing the second communication data in the memory, stores the second communication data in the second storage area; It is determined whether or not data can be stored in the second storage area. When the second communication data cannot be stored in the second storage area, the data is stored before overflowing the second storage area. Second processing means for requesting an expansion storage area to expand the storage area for the second communication data, and an expansion storage area of the memory in accordance with requests from the first processing means and the second processing means To For serial first communication data and the second
Setting means for setting a predetermined amount of storage area for communication data of the first communication data and the second communication data.
The communication data can be stored in the memory in parallel.

Embodiment An embodiment of the present invention will be described below in detail with reference to the drawings. In the following embodiment, a facsimile apparatus to which a plurality of lines can be connected will be described as an example. In the following embodiments, a facsimile apparatus to which three communication lines can be connected will be described as an example.

FIG. 1 is a block diagram showing the configuration of the entire facsimile apparatus of this embodiment.

In FIG. 1, reference numerals 1a, 2a, and 3a denote communication lines, respectively.
Reference numerals 1, 2, and 3 denote communication control units that perform data communication control (including data transmission and data reception) corresponding to the communication lines 1a, 2a, and 3a. In this embodiment, various communication lines such as a general telephone line (analog line) and a digital line can be connected. In this case, the communication control unit performs communication control corresponding to the type of each communication line. For example, when the communication line 1a is an analog line, the communication control unit 1 controls communication of G3 facsimile recommended by CCITT. When the communication line 2a is a digital line, the communication control unit 2 controls G4 facsimile communication recommended by CCITT.

Reference numeral 4 denotes an image memory for storing image data.
The image memory 4 has a communication control unit 1 as shown in FIG.
Transmission / reception area 4-1 of (CCU1), communication control unit 2 (CCU2)
, A transmission / reception area 4-2 of the communication control unit 3 (CCU3), and a release area 4-3 where all of the CCU1, CCU2, and CCU3 can be used. Note that the transmission / reception areas 4-1 and 4-2 and 4 in the image memory according to the present embodiment are used.
-4 and a release area 4-3 each have a storage capacity of about 50 A4 standard originals (image data encoded by a modified read method). However, the memory capacity is not limited to the above. In this embodiment, the capacity of each area is set to the same capacity. However, when the amount of data handled among the three communication lines is large, the memory capacity of the area may be set large.
The encoded image data is stored in the image memory 4, and the encoding method is naturally different depending on each of the communication control units 1, 2, 3 and the communication partner. For example, in the G3 facsimile, the Modified Huffman system (MH system) and the Modified lead system (MR system) are common,
In the G4 facsimile, a mode-adjusted mode-read system (MMR system) is generally used. The image memory 4 of the present embodiment can store image data of different encoding systems.

Reference numeral 5 denotes a codec for encoding and decoding image data. The codec unit 5 includes an encoder that performs MH, MR, and MMR encoding, and an MH, MMR,
R and MMR decoders,
The encoding method and the decoding method are selected based on control by the control unit 8.

Reference numeral 6 denotes a reader for reading a document image, and outputs the read image data (uncompressed) to the codec unit 5.

A printer 7 records image data (uncompressed) output from the codec unit 5 on recording paper.

Reference numeral 8 denotes a control unit for setting an area of the image memory 4 and selecting an encoding / decoding method. The control unit stores a microcomputer and a control program of the microcomputer, and a read only memory (RO).
M), random access memory (R
AM), and peripherals of a micro computer such as input / output ports (I / O ports) for transmitting and receiving data to and from the CCUs 1, 2, and 3 and the like.

A schematic operation of the present embodiment will be described based on the above configuration.

First, in the present embodiment, each CCU controls data storage in each transmission / reception area of the image memory 4. And each C
The CU determines whether or not the image data of the next page (regardless of whether or not the next page actually has) can be stored while the image data of one page is stored, and the storage of the image data of the next page is impossible. At this time, an extension request signal is sent to the control unit 8 as an interrupt signal. When receiving the extension request signal, the control unit 8 determines whether or not there is an empty area in the release area 4-3 of the image memory 4, and if there is an empty area, the extension address (release Area 4-3
The start address and end address of the middle extension area are set, and the set extension address is notified to the CCU. Thus, even if the transmission / reception area of the image memory 4 is likely to overflow during data communication, the data storage area is expanded to the release area 4-3.

FIG. 3 is a flowchart showing a control operation of the CCU (common to CCUs 1, 2, and 3) in the present embodiment. The flow chart shows the control operation of a communication controller (constituted by a microcomputer or the like) provided in the CCU.

4 and 5 are flowcharts showing the control operation of the microcomputer of the control unit 8.

Hereinafter, description will be given based on the flowcharts of FIGS. 3, 4 and 5.

 First, the control operation of the CCU will be described.

In step s1 of FIG. 3, it is determined whether or not an instruction to transmit image data has been input from an operation panel (not shown), and in step s2, a call signal (CI signal) from a communication line.
Is determined. When the transmission instruction is input, the process proceeds from step s1 to step s3, and when the CI signal is received, the process proceeds from step s2 to step s36.

When the process proceeds to step s3 in response to the transmission instruction, it is determined in step s3 whether or not the number of transmission documents has been input in advance by an operation panel (not shown). If the number of originals has not been input in advance, the process proceeds to step s4. At step s4, it is determined whether or not there is a free area for storing at least one page of image data in the transmission / reception area of the image memory 4. In this case, the image data of one page is, for example, if the image data to be transmitted is A4 size image data,
If the transmission image data is B4 size image data, it is image data for one B4 size standard document. The standard image data for one page is CC
U or will be encoded according to the communication partner,
The standard image data amount differs depending on the encoding method. Therefore, in the present embodiment, the standard image data amount is selected based on the encoding method performed by the CCU in the transmission, and it is determined whether or not the selected standard image data amount can be stored in the memory.

If there is an empty area of one or more pages in the transmission / reception area in step s4, the operation proceeds to step s8. If there is no empty area of one or more pages, the operation proceeds to step s5. Then, in step s5, an extension request signal for the transmission / reception area of the image memory 4 is sent to the control unit 8. If there is a free area in the release area 4-3 of the image memory 4 and an extension address is set by the control unit 8, this is received in step s6 and the process proceeds to step s8. On the other hand, there is no vacant area in the release area 4-3 of the image memory 4, and the control unit 8 sends an extension-impossible signal.
When this is received in step s6, the flow advances to step s7 to execute a memory overflow process. Here, as the memory overflow processing, an operation panel (not shown) displays that the memory is full and that memory transmission is not possible.

In step s8, the control unit 8 is notified of the coding method, and the control unit 8 selects the coding method of the encoder of the coating 5. And step s9
Sends a read start command to the reader 6 to read one page of the originals set in the reader 6. When the reader 6 inputs a reading start command from the CCU, the reader 6 starts reading one page of the original, and outputs the read image data to the encoder of the codec 5. The encoder of the codec 5 sequentially codes the image data from the reader 6 And outputs encoded and encoded image data (compressed data).

In step s10, the CCU starts storing the encoded image data in the transmission / reception area of the image memory 4. Then, during the storage of the image data, in step s11, it is determined whether or not the memory capacity for storing the next page image data is in the transmission / reception area.
Proceed to s12, and if there is space for the next page, proceed to step s22. At step s22, it is determined whether or not the reading operation of one page being read has been completed, and when the reading of one page has been completed, the data storage in the image memory 4 is stopped, and step s2 is performed.
In step 3, it is determined whether or not the next page of the original is set in the reader 6. If the next page document is set in step s23, the process returns to step s9. If the next page document is not set, it is determined that reading of all documents has been completed, and the process proceeds to step s24. In step s24, the CCU connects the communication line with the transmission destination, and executes the communication method (for example, G
The image data stored in the image memory 4 is transmitted by 3 facsimile communication, G4 facsimile communication, or the like. When it is determined in step s25 that the memory transmission has been completed, the line is released and the processing is terminated.

On the other hand, in step s11, it is determined that the memory capacity for the next page is not in the transmission / reception area, and the process proceeds to step s12.
When the extension request signal is transmitted to the control unit 8 and the extension address is transmitted from the control unit 8 as described in step 5, the process proceeds from step s13 to step s17, and the control unit 8
Upon receiving a more non-extendable signal, the process proceeds from step s13 to step s14. At step s14, it is determined whether or not the reading of one page of the document being read has been completed. When the reading of one page has been completed, data storage in the image memory 4 is stopped, and the process proceeds to step s15. At step s15, it is determined whether or not the next original is set in the reader 6. If the next original is not set in the reader 6, the process proceeds to step s24 to perform memory transmission. If there is the next original, the process proceeds to step s16. Step s7
Displays that the memory has overflowed.
Here, in this embodiment, there is also provided a mode in which a document already read and stored in the image memory 4 is transmitted in memory, and the remaining documents are read and transmitted in real time, and this mode is designated by the operator. Then, the memory transmission is started when the memory overflows. Then, following the end of the memory transmission, the real-time reading transmission is performed.

Proceeding from step s13 to step s17, step s17
It is determined whether or not the reading operation of one page being read is completed. When the reading of one page is completed, data storage in the image memory 4 is stopped, and the next document is set in the reader 6 in step s18. It is determined whether or not. Step s1
If it is determined in step 8 that there is no next original, in step s21, a signal for canceling the extension address received from the control section 8 is sent to the control section 8, and the flow advances to step s24. Thus, the extension request sent in step s12 is canceled.

If it is determined in step s18 that the reader 6 has the next original,
At step s19, a read start command for the next page is sent to the reader 6, and at step s20, storage of the encoded image data in the transmission / reception area expanded by the capacity of the extension address received from the control unit 8 is started, and step s11 starts. Return to

As described above, in steps s8 to s25, when the transmission / reception area becomes insufficient while the original is read and stored in the image memory 4, the CCU issues an extension request to the control unit 8 each time, and the release area 4 of the image memory 4 is read. If there is a free area in 3, the transmission / reception area is extended.

On the other hand, if the number of originals to be transmitted has been input in advance in step s3, the process proceeds to step s26, where it is determined whether or not there is free space in the transmission / reception area of the image memory 4 for the number of transmissions. In step s26, if there is free space, the process proceeds to step s30. If there is no free space, the process proceeds to step s27.
An extension request signal is sent to the control unit 8 in the same manner as 5. Then, in step s28, information on the amount of memory expansion is sent to the control unit 8 so as to expand at least by the insufficient memory capacity, and when the extension address is received from the control unit 8 in step s29, the transmission / reception area is expanded. Proceeding to step s30, when the extension disable signal is received from the control section 8 in step s29, the process proceeds to step s35 to execute a memory overflow process.

When the process proceeds to step s30, the control unit 8 is notified of the encoding method as in step s8, and a read start command is sent to the reader 6 in step s31. Then, storage of the coded image data in the image memory 4 (transmission / reception area) is started in step s32, and it is determined in step s33 whether one page has been read. When the reading of one page is completed, it is determined in step S34 whether or not all the originals have been read. If all the reading has not been completed, the process proceeds to step S34.
Returning to s31, the next page is read, and if all readings have been completed, the process proceeds to step s24 to perform memory transmission.

In the above steps s3, s26 to s35, since the memory capacity is expanded in advance by a necessary amount, it is not necessary to expand the memory every time a shortage occurs.

The above is the memory transmission operation. If it is determined in step s2 that the reception is performed, the following operation is performed.

In step s2, it is determined that the data is received. When the process proceeds to step s36, a communication protocol (communication procedure) before communication is executed based on a data communication method corresponding to the transmitting side and each CCU. At step s37, it is determined whether or not the number-of-transmitted data has been sent from the other party according to the pre-communication protocol. If the transmission number data has not been received from the destination in step s37, the process proceeds to step s38. If the transmission number data has been received, the process proceeds to step s64.

In step s38, it is determined whether or not at least one page of standard document data can be stored in the transmission / reception area, as in step s4. The encoding method and image size of the transmitted image data are received from the other party using the pre-communication protocol, and the standard data amount is selected according to the received information. If there is no free space of at least one page in the transmission / reception area, steps s39, s5 in steps S40,
In the same manner as in s6, a request for expanding the transmission / reception area is made. When an expansion disable signal is received, the flow advances from step s40 to step s41 to execute a memory overflow process. In addition, step s4
In the memory overflow process in step 1, a mode (real-time reception) in which the destination is notified that the memory capacity is insufficient and the memory cannot be received and the image data received by the destination is printed out in real time by the printer 7 is selected. When it does, real-time reception is executed.

When the transmission / reception area of the image memory 4 is extendable and an extended address is received in steps s39 and s40, the transmission / reception area is extended by the received extended address, and step s4 is performed.
Proceed to 2. At step s42, the mode is set to the reception mode specified by the other party by the protocol before communication, and step s4
The storage of the image data received in step 3 in the transmission / reception area is started. Then, during memory reception, it is determined in step s44 whether or not there is free space in the transmission / reception area to store the image data of the next page. If there is free space, step s5 is performed.
The process proceeds to step S6, and if there is no free space, the process proceeds to step s45, where an extension request signal for the transmission / reception area is transmitted to the control unit 8. When the extension address is received from the control portion 8 in step s46, the process proceeds to step s50, and when the extension disable signal is received from the control portion 8, the process proceeds to step s47. In step s47, it is determined whether or not a page end signal has been received from the other party.
In step s48, it is determined whether or not a signal indicating that there is a next page is received from the other party. If there is no next page, the process proceeds to step s59. If there is a next page, a memory overflow process is executed in step s49.

On the other hand, the extension address is received in step s46, and step s50
In step s47, it is determined whether or not a page end signal has been received, as in step s47. When the page end signal has been received, step s51 determines whether or not the next page has been received, as in step s48. If the next page has not been received, the process proceeds to step s59. If the next page has been received, the process proceeds to step s52.
Then, the communication protocol between the pages is executed, and if there is a change in the reception mode, the reception mode is reset in step s53, and then the reception of the image data of the next page is started in step s54.

Then, the storage of the received image data in the extended transmission / reception area is started in step s55, and the process returns to step s44.

If there is a free area (capacity) for storing the image data of the next page in the transmission / reception area in step s44, the process proceeds to step s56 to determine whether or not a page end signal has been received as in step s47. When the page end signal is received, in step s57, it is determined whether or not the next page has been received, as in step s48. If the next page has been received, step s5 is performed.
After executing the inter-page protocol in step 8, the flow returns to step s42 to receive the next page. If the next page is not received in step s57, it is determined that the reception is completed, and the process proceeds to step s59.
After executing the termination protocol (post-procedure) in step s59, the line is released, and the flow advances to step s60.

In step s60, an extension request for the transmission / reception area is made and the extension address is received from the control unit 8. However, when the image data of the next page is not actually received, the control unit 8 is notified of the cancellation of the extension address. When the image data is stored in the extended transmission / reception area, the cancellation of the extension address is not performed.

Next, in step s61, the control unit 8 is notified of the decoding method of the image data received in the memory. As a result, the control unit 8 selects the decoding method of the decoder of the codec 5. In step s62, the image data received in the memory from the transmission / reception area of the image memory 4 is read out, supplied to the decoder of the codec 5 to sequentially expand the image data, and then printed out on a recording paper by the printer 7. If it is determined in step s63 that the recording has been completed, all the processes are completed.

According to the above steps s38 to s63, if the transmission / reception area of the image memory 4 becomes insufficient during the memory reception, an extension request signal is sent to the control unit 8 each time, and when the extension address is received from the control unit 8, the extension is performed. The transmission / reception area is extended by the address.

On the other hand, when the information on the number of transmissions is received from the transmission side in step s37 (when the transmission number data is received)
In step s64, it is determined whether all image data can be stored in the transmission / reception area of the image memory 4 (whether there is a free area in the transmission / reception area). If all the image data can be stored in the transmission / reception area, the process proceeds from step s64 to step s68, and if not, the process proceeds from step s64 to step s65, and an extension request signal for the transmission / reception area is sent to the control unit 8. Then, in step s66, information on the memory capacity to be expanded (information on the amount of expansion) is sent to the control unit 8. When the control unit 8 receives the extension amount information following the extension request signal, the control unit 8 determines whether or not there is a free area for the received extension amount in the release area 4-3 of the image memory 4. And the extended address
Send to CCU. Also, the control unit 8 has a release area 4-
If there is no free area in No. 3, an extension disable signal is sent to the CCU.

In step s67, when the CCU receives the extension address, it expands the transmission / reception area, and then proceeds to step s68. When the CCU receives the non-expansion signal, it proceeds to step s74 to execute the memory overflow process. When the process proceeds to step s68, the reception mode is set in the same manner as in step s42, and the process proceeds to step s69.
Starts memory reception to the transmission / reception area. When it is determined in step s70 that the page end signal has been received, it is determined in step s71 whether a signal indicating the presence of the next page has been received. If the signal indicating the presence of the next page has been received in step s71, the inter-page protocol is executed in step s72, and the process returns to step s68 to receive the next page.
If it is determined in step s72 that the next page has not been received, the flow advances to step s73 to execute the end protocol in the same manner as in step s59, and then to step s61 to record and output the image data received in the memory.

In the above steps s64 to s74, if information on the number of images to be transmitted (the amount of image data to be received) is received from the transmission side in advance of receiving image data, a memory capacity for the amount of image data is secured. Therefore, there is no need to extend the transmission / reception area during image data reception.

When the transmission of the memory is completed or the printout of the image data received in the memory is completed, each CCU sets the transmission / reception area in which the image data is stored as an empty area. If there is an extension address of 4-3, the control unit 8 is notified to cancel the extension address of the release area 4-3.

 Next, the control operation of the control unit 8 will be described.

First, the flow chart of FIG.
Is a main routine that is normally executed.

At step M1, the monitoring of the empty area of the image memory 4 and the abnormality monitoring of the image memory are performed.

In step M2, the operation of each of the CCUs 1, 2, and 3 is monitored. In step M3, the operation of the reader 6 is monitored, and in step M4, the operation of the printer 7 is monitored.

That is, in the present embodiment, the CCUs 1, 2, and 3 operate independently, and each CUU accesses the image memory independently.
While one CCU is transmitting memory, another CCU can receive memory. However, since only one reader 6 and one printer 7 are provided, the operation of the CCU is partially restricted. That is, when the reader 6 or the printer 7 is used by one CCU, the other CCU cannot use the reader 6 or the printer 7. For this purpose, the control unit 8
Monitors the operation status of the reader 6 and the printer 7, and
When U reads a document from the reader 6 and stores image data in the image memory 4, if another CCU requests an operation of the reader 6, the reader 6 is busy (in use) to another CCU. Notify that there is. Then, when the reader 6 becomes unused, it notifies another CCU that has requested the operation that the reader 6 can be used. The case of the printer 7 is the same as the case of the reader 6 described above.

This enables the following parallel operation in this embodiment.

That is, three CCUs can perform memory reception to the image memory 4 in parallel, and the same applies to memory transmission from the image memory 4. When the reading of the document by the reader 6 under the control of one CCU is completed, the reading of the document by the control of another CCU is possible, and the memory transmission from the image memory 4 and the reading of the document by one CCU are possible. is there. The parallel operation of the reader 6 and the printer 7 is also possible.

As described above, the control unit 8 normally executes the monitoring operation shown in the flowchart of FIG. 4, but when receiving various request signals from the CCU, executes the interrupt program shown in the flowchart of FIG. .

First, in step N1, the CCU that has issued the interrupt request is recognized, and which CCU request has been requested is recognized. And step N
2 if the request signal is an extension request signal for the transmission / reception area,
In step N11, it is determined whether the communication signal is an encoding / decoding system communication signal or in step N13 whether it is a cancellation notification of an extension address. If the signal is an extension request signal, the encoding / decoding system is transferred from step N2 to step N3. Step N1
The process proceeds from step 1 to step N12, and if it is the cancellation of the extension address, the process proceeds from step N13 to step N15. If none of the above, the process proceeds from step N13 to step N14 to execute another process.

If the received request signal is an extension request signal, step N2
Then, the process proceeds to step N3, where it is determined whether or not the extension amount information has been sent from the CCU following the extension request signal. If the extension amount information has been received, the process proceeds to step N4 where the release area 4 of the image memory 4 is determined. Then, it is determined whether or not there is a free area at least equal to the requested expansion amount. And step N4
If there is a free space in the release area 4-3 equal to or larger than the extension amount, the extension address (start address and end address) of the free area corresponding to the extension amount is set as a use area in step N5, and step N6 is performed.
Notifies the requesting CCU of the extension address. If there is no room for the expansion amount requested in step N4, the flow advances to step N10 to send an expansion disable signal to the CCU that has requested the expansion.

On the other hand, if the extension amount information has not been received from the CCU in step N3 following the extension request signal, the image memory 4
It is determined whether there is a free area in the release area 4-3 of
If there is no vacant area in the release area 4-3, the flow advances to step N10 to send an extension impossible signal to the CCU. If there is an empty area in the release area 4-3 in step N, the process proceeds to step N8 to set an extended area in the release area 4-3. If there is a vacant area (capacity capable of storing about five A4 size standard images by encoding), an extension address for a predetermined amount is set. After setting the address of the vacant area as the extension address and using the set extension address as the used area,
Notify the extended address set to the requested CCU in N9.

The memory capacity (unit of expansion) to be basically extended can be arbitrarily set by an operator panel shown in FIG. FIG. 8 is a flowchart showing the control operation of the control unit 8 in that case.

 The setting operation of the extension unit will be described later.

If the request from the CCU is a notification of the encoding / decoding method, the process proceeds from step N11 to step N12, and
Is set to the method notified by the CCU.

If the request from the CCU is a cancel notification of an extended address, the process advances from step N13 to step N15 to set the extended address of the release area 4-3 added to the cancel notification from the used area to the free area.

As described above, the control unit 8 responds to the extension request from the CCU and extends the transmission / reception area of the requested CCU if there is a free area in the release area 4-3 of the image memory 4.

Next, the setting operation of the extension unit will be described based on the flowchart of FIG.

First, in step 3-1, when the depression of the selection key 71 in FIG. 7 is detected, the extension unit setting routine starts. Then, in step 3-2, the display unit 74 (liquid crystal display)
Next, guidance display (image size, number of images, encoding method of standard image data, etc.) for inputting the extension size (extension unit) is performed.

Next, the end of the input is recognized in step 3-3, and if the input has not been completed, the expansion size is input in accordance with the input of the numeric key 73 in step 3-4. And step 3-3
When it is determined that the input is completed, the set key 72 is set in step 3-5.
The extension unit setting routine is terminated on the condition that the button is pressed.

This allows the operator to arbitrarily set the extension unit extended in step N8 in FIG.

The release area is provided below a transmission / reception area of a CCU (a CCU connected to a digital line) for transmitting / receiving image data at high speed. When the transmission / reception area immediately above the release area is extended, the extension address is sequentially set from the top of the release area so that the end address of the transmission / reception area and the start address of the release area are continuous. Another CCU (C that transmits and receives image data at low speed)
For CU), an extension address is set from below the release area. This is because, when image data is transmitted and received at high speed, if the addresses on the memory are far apart, it takes time to search for addresses, which affects the reception of image data. In this regard, by providing the release area as described above and setting the extension address, even if the transmission / reception area is extended at the time of high-speed reception, the area is extended with a continuous address, so that the memory reception can be performed smoothly.

In the above-described embodiment, the microcomputer of the control unit 8 performs the extended control of the transmission / reception area according to the request from the CCU. However, the control unit 8 may be configured as shown in FIG.

In FIG. 6, controllers (ch1, ch2, ch3) for extending the transmission / reception area for CCUs 1, 2, 3 are provided. Then, the row address and column (c) of the release area of the image memory 4
olumm) There is provided a row / column extension switch 81 for counting addresses in the address use area. Further, a register 82 storing the limit address value of the release area is provided, and a comparator 83 for comparing the address value to the extended switch 81 and the register 82 is provided.

Next, the operation of the control unit 8 'in FIG. 6 will be described. CCU1, CCU2, and CCU3 each independently make an extension request to ch1, ch2, and ch3. The extension controllers ch1, ch2, and ch3 count up the row address and the column address of the extension switch 81 by the preset extension address. At this time, the count value counted up by the extension switch 81 and the address value of the register 82 are compared by the converter 83, and the count value of the extension switch 81 is stored in the register 82.
If the address value is larger than the address value, the comparator 83 outputs an interrupt signal indicating the extension addition to the requested CCU. Also, from the expansion controllers ch1, ch2, ch3 to CCU1, 2, 3
Is notified of the extension address.

According to the above configuration, an extension unit can be set for each CCU.

When the extended controllers ch1, ch2, and ch3 receive an instruction to release the extended area from the CCU, each extended controller releases the extended area. At this time, the extension switch 81 counts down the count value of the used area by the released amount.

The extension switch 81 has a row address column map and a column address map of the release area, and sets "1" for an address in use and "0" for an empty address to manage the use state of the release area. doing. Each extended controller detects whether there is an empty area in the release area based on this map, and if there is an empty area, expands the transmission / reception area. Then, upon receiving a release command from the CCU, the extended area is released. At this time, the expansion switch
81 is “0” for the Madres map corresponding to the open area
Set.

As described above, according to the present embodiment, one image memory is
CCU can be used effectively.

That is, during image data communication, if the storage capacity is insufficient in the transmission / reception area allocated to each CCU, the transmission / reception area is extended if there is a free area as a release area, so that the image memory can be used effectively. . In particular, when one memory is accessed in parallel by a plurality of CCUs over a plurality of lines, the memory can be used effectively.

In the above-described embodiment, the facsimile apparatus is described in Example 1. However, the present invention is not limited to the facsimile apparatus, but may be applied to a data communication apparatus that communicates code data, such as a teleprocessor or a word processor having a communication device. Is also widely applicable.

In the above-described embodiment, the number of lines that can be accommodated is not limited to three, but may be four or more or two.

[Effects] As described above, according to the present invention, in the data communication device capable of executing at least the first communication and the second communication in parallel, the communication data of the first and second communication is stored. Memory can be used effectively, and even if two different communication data are stored in the memory in parallel,
The communication data can be appropriately stored in the memory without overflowing the storage of each communication data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of the facsimile apparatus of the present embodiment, FIG. 2 is a diagram showing an area of an image memory, FIG. 3 is a flowchart showing a control operation of a CCU, FIG. 4 and 5 are flowcharts showing the control operation of the control unit 8, FIG. 6 is a block diagram showing the configuration of a control unit 8 'according to another embodiment, and FIG. 7 is an operator panel. FIG. 8 is a flowchart showing the control operation of the control unit 8 when the extension unit is set. 1, 2 and 3 are communication controllers, 1a, 2a and 3a are communication lines, 4 is an image memory, 5 is a codec, 6 is a reader, 7 is a printer,
8 is a control unit.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Minoru Ogata 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Kazutoshi Hisada 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tomoyuki Haganuma 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-57-81766 (JP, A) Jpn. (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04N 1/21 H04N 1/00 H04N 1/32

Claims (2)

(57) [Claims] 1. A data communication device capable of executing at least a first communication and a second communication in parallel, wherein the data of the first communication and the data of the second communication are stored. A memory having a first storage area for storing communication data, a second storage area for storing the second communication data, and an extended storage area capable of storing the first and second communication data; When storing the communication data in the memory,
Storing the first communication data in the first storage area; determining whether or not the first communication data can be stored in the first storage area during the storage processing;
When the communication data of the first communication area cannot be stored in the first storage area, the first communication area requests the expansion storage area to expand the storage area for the first communication data before overflowing the first storage area. Processing means, when storing the second communication data in the memory,
The second communication data is stored in the second storage area, and during the storage processing, it is determined whether or not the second communication data can be stored in the second storage area.
When the communication data of the second storage area cannot be stored in the second storage area, a request for expanding the storage area for the second communication data to the expansion storage area before overflowing the second storage area. Processing means; and a predetermined amount of storage area for the first communication data and the second communication data in an extended storage area of the memory in accordance with a request from the first processing means and the second processing means. A data communication device, comprising: setting means for setting the first communication data and the second communication data in the memory in parallel. 2. A data communication apparatus according to claim 1, further comprising means for designating said predetermined amount of storage capacity to be expanded by said setting means.