JPS61190650A - Dma transfer possibility/impossibility reporting system - Google Patents

Abstract

PURPOSE:To perform DMA transfer efficiently by receiving a DMA transmission transfer permitting signal from an IP unit part, which is connected between a facsimile terminal and a host computer, by a communication processor after the end of DMA transmission and DMA-transferring picture information of the following page. CONSTITUTION:A connecting device between the host computer and the facsimile terminal consists of the communication processor and the IP unit part, and this unit part is provided with a DMA transmission transfer permitting signal generating means. Every one block consisting of parts F, M, and L of one-page components of picture information stored in the communication processor is transmitted to the IP unit part and is expanded and developed, and thereafter, a following page indicating command PMC is transmitted from the host computer to the IP unit part to store compressed picture information in the idle area of an image memory, and a DMA reception transfer request signal DR from the communication controller is received by the unit part, and the compressed information is transferred following a DMA reception transfer permitting signal PWK.

Description

[Detailed Description of the Invention] [Summary] In order to transmit image information to multiple facsimile terminals, the present invention temporarily stores it in an image memory and processes such as compression, expansion, and DMA transfer when transmitting image information to multiple facsimile terminals via a facsimile connection device. The present invention relates to a method for effectively controlling transfer by notifying whether DMA transfer is possible or not at that time.

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for effectively controlling transfer when performing DMA transfer within a facsimile connection device used to transmit image information to a plurality of facsimile terminals under the control of a host computer.

[Prior Art] When sending data to a facsimile terminal, the configuration shown in FIG. 2 is employed. In Fig. 2, l indicates the host computer, 2 indicates the facsimile connection device as a whole, and 3
is line connection device NCU, 4 is switching network NW, 51, 5
2-=5 n indicates a facsimile terminal FAX, 20 indicates one communication processing device LCA, and in this example, there are three other similar communication processing devices. The numbers 21 and below indicate each component in the communication processing device 20, 21 is an ink interface with the host computer 1, and 22 is a microprocessor M.
PU, 23 is the main memory section MM, 24 is the facsimile terminal 5
Interface with 1st class, 25 is buffer, 26 is DM
A transfer control section 27 generally indicates the IP unit section.

In the IP unit section 7, 31 is a microprocessor μP, 32 is a main memory MEM, 33 is a CG converter, 3
4 is an expansion/compressor, 35 is a memory controller, and 36 is an image memory. When the same image information is sequentially sent from the host calculation fit to each facsimile terminal, the image information of one page is sent to the first block (F), the second block (M), and the third block.
Assuming that the data is divided into blocks like block (L), the 0 block is temporarily stored in the main memory 23 (MM) in the facsimile connection device 3, and then read from the I block and transferred to the IP unit section 7 using the DMA transfer method. Transfer image information. Third
The figure is a diagram illustrating the transfer of each block and the storage/reading situation in the main storage section 32 and image memory 36 of the IP unit part 7. That is, the first block (F) is sent from the communication processing device 20 (LCA) following the DMA transmission request signal D-W. (Thick arrow 41) Next, following the DMA end signal D-E and the DMA transmission request signal D-W, the second
Block (M) is sent out. (Thick arrow 42°) Then, following the DMA end signal DE and DMA transmission request signal D-W, a third block (L) (thick arrow 43) and a DMA end signal DE are sent out. When the third block (L) is stored in the main memory 32, the decompressor 34 is activated under the control of the microprocessor 31, and the information is decompressed and developed in the image memory 36.

When decompression and expansion are completed, a next page instruction command PMC is sent from the host computer to the microb (processor 31μP) of the IP% knit section 27. The microprocessor 31 instructs whether the page is the last page, whether there is a next page, whether the pixel density needs to be changed, etc.
μP is 1 expanded in the image memory 37 here.
The image information of the page is read out, the compression processing section of the expansion/compressor 34 is activated, and the compressed image information is stored in the free area in the image memory 37 as shown in the middle row on the right side of FIG.

Next, the host computer sends a DMA reception transfer request signal D-R to the IP unit section 7, and under the control of the microprocessor 31μP, the image information in the image memory is transferred one block at a time to the main memory of the communication processing device. Transferred to 23. The DMA end signal D-E and the DMA reception transfer request signal D-R are repeatedly sent every time image information is transferred.

[Problems to be Solved by the Invention] The capacity of the image memory 36 of the IP unit section is required to be relatively large in order to store both expanded and compressed image information for one page. And D
Since MA transfer processing involves sequential transmission and reception, the processing speed was not very fast.

SUMMARY OF THE INVENTION An object of the present invention is to provide an MA status notification system that does not use a large capacity image memory 36, can be used efficiently, and can perform high-speed processing.

[Means for solving the problem] When the IP unit unit recognizes that a free space is created in the image memory when one block of compressed image information is sent to the host side,
Sends a DMA transmission transfer enable signal (R-W-K) to the host side. The communication processing device receives the signal, receives the first block of the first page, and then transmits the first block of the second page using the DMA transfer method.

[Operation] Since the communication processing device and the IP unit can obtain information regarding the free space in the image memory, the free space can be used to efficiently perform DMA transfer.

[Embodiment] FIG. 1 is an explanatory diagram regarding DMA transmission/reception transfer operations as an embodiment of the present invention. The configuration for performing the processing operation shown in FIG. 1 is the same as the conventional one shown in FIG. It is equipped with 31. That is, the hardware shown in FIG. 2 is substantially the same as the conventional one, but since the built-in program is different, the operation also changes after the middle stage of the processing operation shown in FIG. 3.

That is, when one page image information from the host computer is compressed and stored in the image memory 37, the communication control device
The MA reception transfer request signal D-R is sent to the image memory side, and the microprocessor 31 sends a DMA transmission transfer enable signal (R-W-K) as a signal indicating that the DMA reception transfer request signal D-R is ready. will continue to be sent. These signals mean that if the DMA transfer operates as prescribed and the compressed information is sent to the communication control device side, it is possible to write a new DMA transmission transfer in the vacant area. Therefore, the communication processing device that has received the RW- signal next receives the first block (F) of compressed information of one page (hatched arrow 51). Thereafter, the communication processing device sends out a DMA end signal D-E, and sends out the initial block 0 of the next two-page image information. (Thick arrow 44°) After that, the DMA transmission end signal D-E, DMA transmission transfer request signal D-R, and DMA transmission transfer enable signal R-W-K are transmitted and received as described above, and as shown by the hatched arrow 52, the second block ( M) is received by the communication processing device.

Thereafter, the subsequent blocks Fl and Ll of the image information of the second page are transmitted to the image memory side, and the third block (L) of the image information of the first page is received by the communication processing device side.

[Effects of the Invention] In this way, according to the present invention, since the memory capacity in the image memory section can be used effectively, it is possible to achieve the effect of achieving high-speed processing without requiring a particularly large capacity of the memory to be prepared. have

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the operation of an embodiment of the present invention, FIG. 2 is a diagram of the configuration of the image information transmission/reception connection between a facsimile terminal and a host computer according to the present invention and a conventional one, and FIG. 3 is an explanatory diagram of the conventional operation. 1-Host computer 2--Facsimile connection device 51.52--Facsimile terminal 20--Communication processing device 23---Main storage section 27-IP unit section 31--Microprocessor 32--Main storage section 36... - Image memory patent applicant Fujitsu Ltd. agent Patent attorney Eisuke Suzuki LCA memory IP department Memory Figure 1

Claims (1)

[Claims] A facsimile connection device (2) connected between a switching network (4) for switching connections with a plurality of facsimile terminals (51) (52) and a host computer (1). The facsimile connection device (2) includes a communication processing device (20) and an IP unit section (27), and the communication processing device (20) temporarily stores image information from the host computer (1). The main memory section (23) and the image information stored in the main memory section (23) are transferred to the IP unit section (27) by DMA transfer.
and a DMA transfer control unit (26) for storing data in the D
In the method of performing MA transfer, the IP unit section (27)
is equipped with means (31) for emitting a DMA transmission transfer enable signal, and the communication processing device (20) transmits the image information of the previous page after the DMA transmission is completed and after receiving the DMA transmission transfer enable signal from the IP unit section. , a DMA transfer permission notification method characterized by DMA transfer of image information of the next page.