JPS6390270A - Recording system - Google Patents

Abstract

PURPOSE:To successively execute a recording without an interruption, to shorten a processing time, to improve a recording quality and to reduce a recording noise by controlling the recording time of a recording part based on the number of residual data of a memory and storing the data constantly in the memory. CONSTITUTION:A system control part 22, when the number of the residual data D0 of a line memory buffer 14 is large, operates a delay time td short and operates the delay time td long when the number of the residual data D0 is small and outputs a control signal corresponding to the delay time td to a mechanism control part 21. The mechanism control part 21, based on the control signal from the system control part 22, output a driving pulse to the recording paper feeding pulse motor of a plotter 19 or a pulse voltage to a recording electrode. Accordingly, the reducing speed of the data outputted according to a DMA in the plotter 19 of the line memory buffer 14 can be controlled based on the number of the residual data D0 in the line memory buffer 14 and a state in which the data is constantly present in the line memory buffer 14 can be maintained.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a recording method, and in particular, to a direct memory
It relates to a recording method that transfers and records data upon access.

(Prior Art) In recording systems such as facsimile machines and laser printers, in order to shorten processing time, data is transferred from the memory to the recording unit using direct memory access (hereinafter abbreviated as DMA) and recorded. Is going.

For example, in a facsimile machine, as shown in FIG. 3(a), data input via an external line can be processed by a data compression/reproduction unit (data processing unit) 1 in a block (recording unit) 2. When the data is reproduced (processed) and stored in the line memory buffer 3, the data is stored in the memory field ff1 (usually 256 bytes) x 64) of the line memory buffer 3, as shown in FIG. 3(b). As shown in FIG. 3, the processing of the data compression/reproduction unit 1 is stopped and data is directly transferred from the line memory buffer 3 to the plotter 2 by DMA. Data is transferred from the line memory buffer 3 to the plotter 2, and when the free space in the line memory buffer 3 reaches 54 lines as shown in FIG. 3(C), the processing of the data compression/reproduction unit 1 is restarted. and sends the processed data to the line memory buffer 3. Therefore, CPU
(central proc-essing uni
The processing time can be shortened compared to program transfer in which data is transferred via registers in step t).

However, in such conventional recording methods,
Usually, the recording time in the recording unit is fixed and the DMA transfer time is faster than the data processing time in the data processing unit, so the data in the memory becomes empty during recording, and recording is interrupted. As a result, DMA transfer stops until the memory is full of data, lengthening the recording processing time, and causing the recording unit to be driven intermittently, causing problems such as uneven recording and start sounds. was there.

(Object of the Invention) Therefore, the present invention controls the recording time of the recording section based on the number of remaining data in the memory, so that data is always stored in the memory, without interrupting recording. The purpose is to perform continuous recording to shorten processing time, improve recording quality, and reduce recording noise.

(Structure of the Invention) In order to achieve the above-mentioned object, the present invention processes image data into data that can be processed by a recording unit in a data processing unit and once writes it in a memory tα, and then transfers the image data to the recording unit by direct memory access. The recording method is characterized in that the recording time of the recording section is controlled based on the number of remaining data in the memory.

Hereinafter, the present invention will be specifically explained based on examples.

FIG. 1.2 is a diagram showing an embodiment of the present invention, which is applied to a facsimile machine.

FIG. 1 is a block diagram showing a facsimile machine. When transmitting, the facsimile device 11 scans the document 12 into the scanner 1.
3 to read the image data, convert it into an electrical signal, and store it in the line memory buffer (memory) 14. The image data once stored in the line memory buffer 14 is reduced in data amount (data compression) without losing the original data in a data compression/reproduction device (data processing section) 15, and then transferred via a transmission control section 16. It is sent to modem 17 and modulated.

The image data modulated by the modem 17 is sent to the line via the network control device 18. On the other hand, during reception, the modulated signal (image data) input from the line is guided to the modem 17 via the network control device 18, demodulated, and then transmitted to the transmission control section 16.
The data is sent to the data compression/reproduction device 15 via. The original data is reproduced by the data compression/reproduction device 15 and stored in the line memory buffer 14.

The image data stored in the line memory buffer 14 is sent to a block (recording section) 19 and recorded on a recording paper 20. The plotter 19 is controlled by a mechanism control section 21, and the block 19 includes a pulse motor for feeding recording paper and a recording electrode, and records image data on the recording paper 20 using an electrostatic recording method. The mechanism control section 21 controls the drive of the plotter 19 and the scanner 13 according to instructions from the system control section 22 . The system control unit 22 is a CPTJ (central pro
It is equipped with a facsimile machine (processing unit) and controls the operation unit 23, which is an interface unit with the operator, the line memory buffer 14, the data compression/reproduction device 15, the transmission control unit 16, and the mechanism control unit 2I, and operates as a facsimile machine. Run the sequence. The network control device 18 is an automatic transmission type network control device, and is a so-called AA-N network control device.
This is called CU.

The system control unit 22 uses DMA (Direct M
Data transfer between the line memory buffer 14 and the scanner 13 and between the line memory buffer 14 and the plotter 19 is directly performed by direct memory access. The line memory buffer 14 has a memory space of 256 bytes x 64, and the data compression/reproduction device 15 stores bit map data (maximum 256 bytes) for each line.
is sent to the line memory buffer 14 each time it is processed. The start and stop of processing by the data compression/reproduction device 15 is controlled by the system control unit 22.

Next, the operation will be explained based on the flowchart shown in FIG.

At the time of reception, modulated data (image data) sent from an external line through the network control device 18 is guided to the modem 17,
After being demodulated by modem I7, data compression/reproduction device 15
sent to. The data compression/reproduction device 15 reproduces the sent modulation data (bit map data) line by line into original data (data that can be processed by the plotter 19) and sends it to the line memory buffer 14 (step S). .

Line memory buffer 14 is data compression/reproduction device 11
5, and when all 64 lines have been stored, in step S2), the processing of the data compression/reproduction device 15 is stopped, and a DMA request signal is sent to the DMA control element of the system control section 22. Output (step S3). Based on this DMA request signal, the DMA
The IIW element exchanges signals with the CPU of the system control unit 22 to stop the execution of the CPU, controls the pass line, and starts direct data transfer by DMA from the line memory buffer 14 to the block 19 (step S3). , this data transfer is performed line by line, and the plotter 19 records the sent data line by line (step S
4).

However, data for one line is sent from the line memory buffer 14 to the plotter 19 by DMA.
9 (hereinafter referred to as data transfer time) is faster than the time required for the data to be processed by the data compression/reproduction device 15 and stored in the line memory buffer 14. Therefore, if the processing of the data compression/reproduction device 15 is restarted when the number of empty lines in the line memory buffer 14 reaches 54, as in the conventional method, the data stored in the line memory buffer 14 will be quickly erased. (It will be gone.

Therefore, in this embodiment, when the line memory buffer 14 becomes free for one line (step SS), that is, when the number of remaining data reaches 63 lines, data compression/
The processing of the playback device 15 is started (step 56). Furthermore, the system control unit 22 calculates the recording delay time in the plotter 19 based on the number of remaining data in the line memory buffer 14, and outputs a control signal to the mechanism control unit 21 to control the recording time (step S?). . That is, the system control unit 22 detects the remaining data number D0 in the line memory buffer 14, and when the remaining data number 00 becomes 63 or less, calculates the delay time t4 using the following equation.

tt+ = (63-Do) x to...
(1) Here, to: data transfer time The system control unit 22 outputs a control signal to the mechanism control unit 21 based on this delay time t4, and the mechanism control unit 21 controls the plotter 19 based on this control signal. Control recording time. That is, the system control unit 22 calculates a short delay time t4 when the remaining data number D0 of the line memory buffer 14 is large, and a long delay time t4 when the remaining data number D0 is small, and outputs a control signal corresponding to this delay time t. is output to the mechanism control section 21. The mechanism control section 21 outputs drive pulses to the pulse motor for feeding the recording paper of the plotter 19 and pulse voltage to the recording electrodes based on control signals from the system control section 22 . Therefore, the decreasing speed of data output by DMA can be controlled by the profiler 19 of the line memory buffer 14 based on the number D0 of remaining data in the line memory buffer 14, and data always exists in the line memory buffer 14. condition can be maintained. As a result, the plotter 19 can perform continuous recording without interruption, shorten the recording processing time, improve recording quality, and reduce recording noise. Further, as is clear from equation (1), the delay time t4 is calculated to be longer as the number of remaining data in the line memory buffer 14 decreases. Therefore, when the number of remaining data in the line memory buffer 14 is large, the recording time is accelerated, and as the number of remaining data in the line memory buffer 14 is decreased, the recording time is delayed.

As a result, the recording time (processing time) can be further shortened.

However, depending on the device, the data in the line memory buffer 14 may become empty even if the processing time in the recording section is delayed due to the interrelationship between the processing capacity of the data processing section and the processing capacity of the recording section. Therefore, in this example as well,
In step Sl+, it is determined whether the remaining data D0 of the line memory buffer 14 is O (zero), and the remaining data number D0 is determined.
When is 0, the DMA transfer is stopped in step S.

Next, step S. In step S, it is determined whether all data processing has been completed, and if all data processing has been completed, initial settings are made in step S, and this flow is ended. In step S11, if the remaining data number D0 is not O, as described above! The number of remaining data D0 calculated using formula 11
A delay time t6 corresponding to this is set and a control signal is output to the mechanism control section 21.

If the data processing is not completed in step SI+1, a control signal corresponding to the delay time t4 when the remaining data number D0 is 0 is output to the mechanism control unit 21 in step SI3. Therefore, once the remaining data number D0 becomes 0, the next recording process will be restarted with the maximum delayed processing time.

In the above embodiments, the case where the present invention is applied to a facsimile machine has been described, but the present invention is not limited to this, and can be applied to general apparatuses that transfer and record data from a memory using a DMA transfer method, such as a laser printer.

(Effects) According to the present invention, the data transferred to the recording section by DMA can always be stored in the memory, and can be continuously recorded in the recording section without interruption. As a result, processing time can be shortened, recording quality can be improved, and recording noise can be reduced.

[Brief explanation of the drawing]

1.2 are diagrams showing one embodiment of the recording method of the present invention, FIG. 1 is a block diagram of a facsimile machine to which the recording method is applied, and FIG. 2 is a flowchart showing the data processing. Figure 3 is a block diagram of the conventional recording system, and Figure 3 (
Figures a), (b), and (c) are block diagrams sequentially showing each deviation of data processing. 11...Facsimile machine, 14...Line memory buffer, 15...
...Data compression/reproduction device (data processing section), 19...
. . . Profiler (recording section), 21 . . . Mechanism control section.

Claims (1)

[Claims] In a recording method in which a data processing section processes image data into data that can be processed by a recording section and temporarily stores it in a memory, the data is transferred to the recording section by direct memory access and recorded. A recording method characterized in that the recording time of the recording section is controlled based on the recording time.