JP3167005B2 - Facsimile machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is provided with a function such as a so-called quick scan for reading a document at a high speed while storing the document in a memory, and a dual access for reading a document in parallel during communication processing. The present invention relates to a facsimile machine.

[0002]

2. Description of the Related Art Conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 4-57463, a memory is provided for storing image data of a document read from a transmission document or image data transmitted / received via a general public line. In such facsimile apparatuses, functions such as a so-called quick scan in which a transmission original is read and stored in a memory within six seconds, for example, and dual access in which transmission original reading processing is performed in parallel during communication processing are required. I have.

In this type of facsimile machine,
For example, as shown in FIG.
This one CPU 1 controls the entire system. The 16-bit system bus 2 of the CPU 1
Has a ROM 3 storing a control program and the like and a backed-up SRAM 4 storing setting data and the like.
A modem 6 connected to a general public line via an NCU (network control unit) 5, and a DR for storing image data to be transmitted or received image data.
Compresses (encodes) AM7 and image data read for transmission, or decompresses (decodes) received image data
And a CODEC IC (encoding / decoding circuit) 8. Further, a printer engine 12 for printing image data and a paper transport motor 14 are connected to the system bus 2 via an ASIC 11 composed of a gate array. Further, the system bus 2 has an image sensor 17 for reading a transmitted original or a C sensor via an image processing IC 15 and a coder IC (encoding circuit) 16.
A CD is connected, and an internal or external line buffer 18 is connected to the CODER IC 16.

In this facsimile machine, an 8 bit
1.5 times faster than CPU
Using 16bit CPU1 and CODEC IC
In addition to the above, a coder IC 16 dedicated to compression for processing image data read by the image sensor 17 is provided .

While [0005] However, as described above conventional, 16bit
CPU1 and CODEC IC for compression and decompression
In addition to the above-described configuration, the configuration including the compression-specific coder IC 16 for processing the image data read by the image sensor 17 has a problem that the manufacturing cost increases and it is difficult to apply it to an inexpensive system. .

Further, a configuration is known in which an accelerator is used instead of the CODEC IC 8 to reduce the load on software. However, there is a problem that the manufacturing cost increases as in the case of using the CODEC IC 8.

Further, in a recording method of a page printer such as a laser printing method, in order to control the printer engine 12 and the like, in addition to the CPU 1 for controlling the entire system,
A configuration using a dedicated CPU and a page memory is known, but such a configuration has a problem that the manufacturing cost is further increased.

[0008]

As described above, 16 bit
CPU1 and CODEC IC for compression and decompression
In addition to the use of the device 8, a configuration including a compression-specific coder IC 16 for processing a document read by the image sensor 17 has a problem that the manufacturing cost increases and it is difficult to apply it to an inexpensive system.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and can perform a reading process of a transmission original quickly and can perform a communication process in parallel with the reading process at a low cost. An object of the present invention is to provide a facsimile machine.

[0010]

According to the present invention, there is provided a facsimile apparatus comprising: reading means for reading read data from a document; communication means for transmitting and receiving communication data ; DRAM as storage means capable of storing the data; a decompression unit can be compressed and decompressed for each data, the pre-printing an image
Comprising a printer engine, and control means for controlling said each means, reads the image data of the document by the reading means, this
Is stored in the DRAM, and the
Image data and read the image data
After the compression processing by the expansion means, the reading stored in the DRAM is performed.
And processing the image data stored in the DRAM
After decompression by the compression / decompression means, buffer in the DRAM
Memory transfer to ring, transfer to communication means and send to line
And the image data received by the communication means to the DRA
Buffering at M and compression processing by the compression / expansion means
After receiving, the memory reception stored in the DRAM and the D
The image data stored in the RAM is decompressed by the compression / decompression means.
Transfer to the DRAM and print out
Out, and the compression / expansion means executes the DR
Decompression processing to read out predetermined data from AM and decompress
Read predetermined data from this DRAM and compress it.
Compression processing is performed in parallel by time division .

[0011]

In the facsimile apparatus of the present invention, the compression / expansion means
Is a decompressor that reads predetermined data from a DRAM and decompresses it.
Long processing, and reading out predetermined data from this DRAM
Example of performing compression processing in parallel with time-division compression processing
For example, the compression / expansion unit sequentially switches and executes a reading process for compressing the read data stored in the storage unit and a communication process for compressing / expanding the communication data stored in the storage unit, thereby reducing the load on the control unit. Meanwhile, the reading process and the communication process are performed in parallel by time division.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a facsimile apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 21 denotes a CPU serving as 8-bit control means, and the entire system is controlled by one CPU 21. The 8-bit system bus 22 of the CPU 21 has a ROM 23 storing a control program and basic function settings, an SRAM 24 backed up by a battery 24a and storing setting data, and the like.
A modem 27 as communication means connected to a general public line via a U (network control unit) 25;
One DRAM 28 as storage means and one CODEC IC (encoding / decoding circuit) 29 as compression / decompression means
And are connected.

The CODEC IC 29 compresses (encodes) the image data, which is the read data read for transmission, and compresses or decompresses (decodes) the image data, which is the transmitted and received communication data, The storage in the DRAM 28 and the printing process are performed. The CODEC IC 29 performs time-division processing,
While performing multiple compression / decompression processes in parallel, DMA
(Direct memory access) It has a function as a controller, and reads and writes directly to the DRAM 28. Furthermore, this CODE
The C IC 29 holds status information indicating to which address in the DRAM 28 the compression / expansion processing has proceeded. When switching between a plurality of compression / expansion processing, the C IC 29 refers to these pieces of status information and refers to the status information in the DRAM 28. Reading, compression / expansion processing, and writing processing are performed on unprocessed data, so that the load on the CPU 21 can be reduced. The DRAM 28 stores image data compressed for transmission and reception, and functions as a line buffer for compressing read data, a page memory for a page printer, and a communication buffer.

The system bus 22 has an image processing I
An image processing IC 31 and an ASIC 32 comprising a gate array are connected.
, An image sensor 33 or a CCD as reading means for reading the transmission original is connected. further,
The ASIC 32 has a printer engine 35 for printing an image on plain paper by an electrophotographic method or a method of ejecting ink.
And a paper transport motor 36 are connected.

When a reading process is performed by the facsimile apparatus, first, as shown in FIG. 2A, image data of a transmission original is read by an image sensor 33, and the image data is binarized by an image processing IC 31. , The ASIC 32 to improve the throughput of the CPU 21
Buffering for 1Byte or 2Byte, 8bitD
The data is transferred to and stored in the DRAM 28 by MA (direct memory access). After this, the CODEC IC 29
The image data is read from the AM 28, the image data is compressed, and then transferred to the DRAM 28 again for storage. In this way, the transmission original is read within 6 seconds per page and the DR is read.
A so-called quick scan stored in the AM 28 is realized. Also, the image data is transferred from the DRAM 28 to the CODEC I
By transferring the data to C29 and compressing it, the DRAM 28 can also serve as a reference line and a line buffer for encoded data.

When performing so-called memory transmission for transmitting image data stored in the DRAM 28, FIG.
As shown in (b), the image data stored in the DRAM 28 is transferred to the CODEC IC 29 by 8 bit DMA and decompressed, buffered by the DRAM 28, transferred to the modem 27 by 8 bit DMA, and transmitted to the line.

When performing so-called memory reception in which the received image data is stored in the DRAM 28 without printing, as shown in FIG.
And buffered in DRAM 28,
After transferring to the CODEC IC29 by MA and compressing, 8b
It is transferred to the DRAM 28 again by itDMA and stored.

Further, when the image data stored in the DRAM 28 is printed out, as shown in FIG. 2D, the image data stored in the DRAM 28 is transferred to the CODEC IC 29 by 8 bit DMA and decompressed.
After developing the data for one page by transferring it to the ASIC,
The printout is sent to the printer engine 35 through the printer 32. Also, by performing this processing continuously with the memory reception shown in FIG. 2C, printer print reception is performed.

Further, by performing the compression / expansion of the transmitted / received image data and the compression of the read image data in parallel, the transmission original can be transmitted in parallel with communication processing such as memory transmission, memory reception, and printer print reception. A so-called dual access can also be realized by performing a read process for inputting a read memory.

For example, a case where a memory input for reading a transmission original is performed during a process of expanding communication data such as a memory transmission will be described with reference to FIG.

First, in processing communication data, COD
EC IC29 is set to decrypt mode and DR
The communication data, which is code data, is read from the AM 28 and decoded (step 1).

Here, when a document to be transmitted is inserted into the image sensor 17, the CPU 21 issues a request for encoding read data (step 2).

In this state, the CODEC IC 29 switches from the decoding mode to the encoding mode while holding the status information such as the address of the DRAM 28 to indicate how far the decoding has progressed, and transmits the communication data. While the decompression work is interrupted, the D
The read data transferred to the RAM 28 is read to start encoding (step 3).

Subsequently, when a predetermined time has elapsed from this state, the CPU 21 issues a request to decrypt communication data (step 4).

In this state, the CODEC IC 29 switches from the encoding mode to the decoding mode while holding status information such as the address of the DRAM 28 in order to indicate how far the encoding has progressed, and reads the read data. The encoding operation is interrupted, and the communication data, which is unprocessed code data stored at a predetermined address of the DRAM 28, is read out with reference to the status information to start decoding (step 5).

Subsequently, when a predetermined time has elapsed from this state, the CPU 21 issues a request to encode read data (step 6).

In this state, the CODEC IC 29 switches from the decoding mode to the encoding mode while holding the status information, interrupts the operation of decoding the communication data, and refers to the status information to read the data of the DRAM 28. Unprocessed read data stored at a predetermined address is read to start encoding (step 7).

By repeating such an operation, dual access is realized by one CODEC IC 29.

Further, even if requests for the third and fourth encoding and decoding are generated, parallel processing can be performed by the above method.

As described above, according to the facsimile apparatus of this embodiment, the CODEC IC 29 manages the DRAM 28,
A decompression process for reading and decompressing predetermined data from the DRAM 28 while following instructions from the CPU 21;
A compression process of reading predetermined data from 28 and compressing it can be processed in parallel by time division. So, CODEC
The compression / expansion capability of the IC 29 can be used as efficiently as possible, and the load on the CPU 21 can be reduced.
Therefore, in order to realize quick access and dual access, it is not necessary to provide a dedicated CODER IC or an accelerator for compressing data in addition to the CODEC IC 29 composed of one IC.
However, the entire system can be controlled by using an inexpensive 8-bit CPU 21 which has a lower processing capacity than a conventionally used 16-bit CPU, thereby simplifying the configuration and reducing the manufacturing cost. Therefore, even for an inexpensive facsimile machine, high functions such as quick access and dual access can be realized.

Further, since the memory, particularly the DRAM 28 for storing image data, is also used as a page memory of a page printer, a line buffer, and the like, it is possible to reduce waste of memory and reduce manufacturing costs. Further, a dedicated CPU is not provided for controlling the printer engine 35 and the like, the number of ASICs 32 is one, and the number of I / O devices is minimized, so that manufacturing costs can be further reduced.

Further, since the system bus 22 is 8 bits, the area of the system bus 22 on the printed wired board (PWD) can be reduced. Therefore, a large mounting area for various components can be ensured, or the size of the printed wired board can be reduced, so that manufacturing costs can be reduced.

In the above configuration, it is possible to sufficiently cope with the 8-bit CPU 21 and the internal processing of the software is 16 bits.
Strict timing is not required to use t CPUs. Also, a 16-bit CPU and a compression-only C
Although the throughput during dual access may be lower than that of the configuration using ODER, the specification and operability of the facsimile apparatus are at a level without any problem. Also,
The processing on the hardware of the ASIC 32 can reduce the processing load on the software of the CPU 21.
Not enough to lead to 32 extreme cost increases. In this way, it is possible to obtain a performance almost equal to that of the conventional example at low cost.

[0035]

According to the facsimile apparatus of the present invention, the pressure
The decompression means reads predetermined data from the DRAM and
Decompression processing, and predetermined data from this DRAM
Read and compress data in parallel with time-sharing
For example, the compression / expansion unit sequentially switches and executes a reading process for compressing the read data stored in the storage unit and a communication process for compressing / expanding the communication data stored in the storage unit. The reading process and the communication process can be processed in parallel by time division while reducing the load. Therefore, there is no need to provide a dedicated means for compressing the read data in addition to the compression / decompression means, and use an inexpensive control means having a low processing capability to simplify the configuration and reduce the manufacturing cost, and to reduce the manuscript size. It is possible to realize so-called quick access for reading at high speed and dual access for performing communication processing while compressing and expanding communication data during the reading processing of the original. Also, DRA
M stores image data compressed for transmission and reception
In addition, line buffer and page for reading data compression
As page memory for printer and communication buffer
The dual use reduces memory waste and reduces manufacturing costs.
Can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a facsimile apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a data flow of the facsimile apparatus.

FIG. 3 is an explanatory diagram showing a data flow of the facsimile apparatus.

FIG. 4 is a block diagram showing a conventional facsimile machine .

[Description of Signs] 21 CPU as control means 27 Modem as communication means 28 DRAM as storage means 29 CODEC IC as compression / decompression means 33 Image sensor as reading means 35 Printer engine

Continuation of front page (56) References JP-A-7-58932 (JP, A) JP-A-7-170351 (JP, A) JP-A-4-250773 (JP, A) JP-A-4-236575 (JP) JP-A-4-363971 (JP, A) JP-A-5-236281 (JP, A) JP-A-6-152431 (JP, A) JP-A-6-169404 (JP, A) 7-30733 (JP, A) JP-A-8-44875 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 1/00-1/00 108 H04N 1/41-1 / 419

Claims (1)

(57) [Claims] 1. Reading means for reading read data from a document
Communication means for transmitting and receiving communication data; and storage means capable of storing the data.As a DRAM
Compression and decompression means capable of compressing and decompressing each of the data;A printer engine for printing images, Control means for controlling each of the means,The image data of the original is read by the reading unit, and the
The data is stored in the DRAM, and the image is read from the DRAM.
Data, and reads the image data into the compression / expansion means.
After the compression process, the reading process stored in the DRAM is performed.
And Means for compressing and expanding image data stored in the DRAM;
After buffering in the DRAM, buffer
Memory transmission to transfer to the communication means and send to the line, The image data received by the communication means is stored in the DRAM.
Buffered and compressed by the compression / expansion means
After that, a memory reception stored in the DRAM, The image data stored in the DRAM is compressed and decompressed by
After decompression, transfer to the DRAM and print out
And print out The compression / expansion means is adapted to store predetermined data from the DRAM.
Decompression processing for reading and decompressing, and predetermined processing from this DRAM
Compression processing for reading and compressing
Process in parallel Facsimile equipment characterized by
Place.