JPH01223845A - Data transmission equipment - Google Patents

Abstract

PURPOSE:To attain data transmission with optimum line state by detecting number of data errors for each prescribed unit for a received transmission data and applying the display based on the detected data error number. CONSTITUTION:A data bit error number is detected for each block of a received picture information data and it is displayed by LEDs 109a-109d in response to data error number to be detected corresponding to a reception error display section 109. Thus, the operator at the reception side can discriminate the quality of the line state of the actual radio line depending on the frequency of occurrence of data error and its magnitude by observing the display in the reception of a picture. Thus, the data transmission is attained with the optimum line state.

Description

[Detailed description of the invention] [Technical field] The present invention relates to a data transmission device.

[Prior Art] Facsimile machines are generally used on telephone lines,
In recent years, wireless lines have also been widely used, such as in car-mounted facsimile machines.

In facsimile communication, image information is transmitted while exchanging various information between a transmitting side and a receiving side using predetermined procedural signals in transmission control.

By the way, compared to telephone lines, wireless lines are more susceptible to noise and the propagation state of radio waves is more likely to fluctuate.
Transmission data is prone to errors.

For this reason, facsimile machines for wireless lines add an error correction code to the data field of the various information and image information to be transmitted, and if there is an error in the received data, the receiving side will detect the error. A process of correction using a correction code is performed.

Normally, in such error correction processing, if the data error rate is below a certain value, the data is corrected to the original correct data, so it is possible to transmit a good image even if the wireless line condition deteriorates to some extent. .

By the way, when communicating via a wireless line, the receiving side wireless device selects an appropriate installation location and adjusts the direction of the antenna, etc., and adjusts the transmission power of the transmitting side wireless device to achieve the best connection. It is desirable to set conditions that improve the condition.

For this reason, the receiving strength of the radio waves is normally adjusted using an S meter provided in the receiving radio device so that the receiving strength of the radio waves is maximized. However, since the actual line condition is greatly influenced by instantaneous noise and external noise, it has not been possible to determine whether the actual line condition is good or bad using the S meter.

Further, even if the condition of the wireless line has deteriorated to some extent as described above, the facsimile machine receives normally, so it is not possible to judge whether the line condition is good or bad from the reception result.

As described above, in the past, there has been a problem in that data transmission cannot be performed in the optimum line condition by determining whether the actual line condition of the wireless line is good or bad.

Incidentally, such problems are not limited to facsimile machines that use wireless lines, but also occur in various data transmission apparatuses that use ordinary telephone lines and perform error correction on the receiving side.

[Objective] It is an object of the present invention to solve the above-mentioned problems and provide a data transmission device that allows an operator to judge the quality of the actual line condition and perform data transmission under the optimum line condition.

[Configuration] For this purpose, the present invention is characterized in that the number of data errors per fixed unit of received transmission data is detected, and a display is performed based on the detected number of data errors. .

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an external perspective view of a wireless facsimile device according to an embodiment of the present invention. In the figure, a rear cover 101 is attached to the upper surface of the bottom frame (not shown) of the facsimile machine M1, and an inner cover 101 is attached to the front part of the rear cover 101.
02 and a front cover 103 are attached. A document insertion slot 104 is formed in the upper part of the front cover 103 on the inner cover 102 side.

Further, an operation button 1 is provided on the front end of the front cover 103.
05a-105c and status display lamps 106a-106c
is installed. A document discharge port 107 and a recording paper discharge port 108 are formed at the lower front of the front cover 103 .

Furthermore, a reception error display section 109 is provided at the other end to display the error occurrence state of the received data.

This reception error display section 109, as shown in FIG.
Green LED 109a and yellow LED 109b, 109
c and red LED 109d are arranged in a row, and corresponding to each one, ro, 1, 2, . COJ is displayed.

FIG. 3 shows a block diagram of a wireless facsimile device. The facsimile device 1 is connected via an interface device 2 to a wireless device 3 which is used for both telephone calls and data transmission. In addition, the interface device 2
A microphone 4 for communicating with the other party is connected to the terminal. The interface device 2 is used to switch between the facsimile device 1 and the microphone 4 for the wireless device 3 .

A scanner 111 inside the facsimile machine 1 reads an image of a transmitted document, and a plotter 112 records and outputs a received image.

The encoding and decoding unit 113 encodes image information to be transmitted and decodes received image information. The operation display section 114 has operation buttons 105a to 105a shown in FIG.
05c, the status display lamps 106a to 106c, and the reception error display section 109.

The communication control unit 115 executes facsimile communication according to a predetermined transmission control procedure, and in this embodiment, the image information to be transmitted is divided into predetermined blocks and transmitted with an error correction code added. The received image information has a function of correcting data errors using an error correction code. The error correction code in this case is, for example, Hamming code, BCH
Known symbols such as codes are used.

The modem 116 modulates and demodulates various information such as image information and procedural signals and transmits the same. The system control section 117 controls each of the above sections to execute predetermined transmission/reception operations.

FIG. 4 shows a circuit diagram of the reception error display unit 109, in which one ends of the LEDs 109a to 109d of each color are connected to the power supply Vc via resistors 109e to 109h, respectively.

The other ends of the LEDs 109a to 109d of each color are connected to two-input open collector NAND elements 109j to 109d, respectively.
1091 output. The above Nando element 10
A decoding circuit is formed by 9i to 1091 and inverters 109m and 109n. This decoding circuit includes a drive signal Sl output from the communication control unit 115,
S2 is input. The drive signals Sl and S2 output the value of a counter (not shown) to be described later as binary data, and one of the LEDs 109a to 109d corresponding to the value is output.
is now lit.

The operation of receiving an image by the facsimile machine 1 with the above configuration will be explained.

In this case, the sending operator usually notifies the wireless device 3 that the document will be sent. Upon receiving the notification, the receiving operator switches the interface device 2 to the facsimile machine Wl side and performs a predetermined receiving operation on the facsimile machine 1. As a result, predetermined facsimile communication is started between the sending side and the receiving side.

In this embodiment, image information is encoded for data compression and transmitted from the transmitting side, and is also divided into blocks each having a certain number of bits, and a predetermined error correction code is added to each block. and sent. In general, error correction codes have a limit on the maximum number of bits that can correct bit errors occurring within each block. In this example, if the maximum number of bits is 2 bits, that is, the bit error in one block of received image information is 2 bits or less,
Be able to correctly correct errors.

As shown in FIG. 5, the facsimile machine 1 on the receiving side sequentially receives the image information and error correction code transmitted in this way (process 501).

Then, using the error correction code, the number of bit errors in the image information data for each block is detected (processing 502
). Here, if there is no bit error (N in process 503)
Then, a counter (not shown) is set to "0" (process 505).

Also, if the bit error is 1 bit (Y in process 504)
), the 1-bit error in the image information data is corrected by a predetermined error correction process (process 506), and the counter is set to ``1''.
” (processing 507).

Similarly, if the bit error is 2 bits (Y in process 503), the 2-bit error in the image information data is corrected by a predetermined error correction process (process 508), and the counter is
2" (processing 509).

Next, the received image information is decoded and it is detected whether correct image information data has been obtained.

That is, when decoding image information, it is necessary to check the make-up code of the image information data, check whether it is defined in the code chip or whether it is data, and check whether the image information data is data or not.
The position of the OL code is checked, and the composite image information for one line is checked to see if it has a predetermined constant number of bits.

As mentioned above, in the above error correction process, if there are 3 or more bit errors in one block, the error is not corrected, so this process checks whether or not the error has been corrected correctly. Process 510).

Here, if no error is detected (N in process 511), one line of image information data is edited and predetermined recording processing is performed (process 512).

On the other hand, if an error is detected (Y in process 511), the counter is set to "3" (process 513), and in this case, the image of the one line in which the data error was detected is not recorded, for example, The pitch for one line is made blank (processing 512).

Then, if there is image information to be received subsequently (processing 514
(Y), returns to the above reception operation and repeats the same process (proceed to process 501). Furthermore, when the processing of the received full-screen information is completed (to step 514), the above reception processing is completed.

FIG. 6 shows a display process for the reception error display section 109 that is activated at the same time as the start of the above reception process.

In the figure, in this display process, it is first determined when any value is set in the counter (process 51).
5).

Here, when any value is set in the counter (Y in process 515), that value is read (process 516).

Then, the currently set value and the previous counter value are compared (process 517), and if the counter value after setting is smaller than the value before setting (N in process 517), the above first process 514 is performed. return.

On the other hand, if the counter value after setting is the same as or greater than the value before setting (Y in process 517),
The value of the counter after the above setting is output as binary data as drive signals Sl and S2 shown in FIG. 4 (process 517).
). As a result, for example, the current counter value is "1".
, yellow 109b, "2", yellow 109
0, and when it is “3”, the red 109d lights up (
Processing 518).

Next, a timer (not shown) that overflows in 2 seconds is started (process 519). Next, it is determined whether or not the image information is being received (step 519), and in that case (N in step 519), the process returns to step 515 and executes the same process.

When the above timer is started, as shown in Figure 7,
The state of the timer is detected (process 521). Then, the timer overflows after 2 seconds (processing 5
21 Y), reset the counter (processing 522).
, process 52 to output the values as drive signals Sl and S2.
3) Stop the timer (processing 524).

As a result, for example, the LEDs 109b to 109d of the reception error display unit 109 that were turned on in the process 517 are turned off after 2 seconds, and the LED 109a is turned on.

Also, for example, if one bit error occurs in one block of image information data and three bit errors occur in another block while the LED 109b is lit, the LE
D109b goes out and LED109d lights up for 2 seconds.

As described above, according to this embodiment, the number of data bit errors is detected for each block of received image information data, and the reception error display unit 109 takes appropriate action according to the detected number of data errors. The lamps are displayed using LEDs 109a to 109d.

Thereby, the operator on the receiving side can judge whether the actual line condition of the wireless line is good or bad based on the frequency and magnitude of data error occurrence by looking at the lamp display when receiving the image. Therefore, if the line condition is not good, the receiving side can select an appropriate location for installing the radio, adjust the direction of the antenna, etc., and the transmitting side can adjust the transmission power. You can set the conditions that will give you the best line condition. This allows data transmission to be performed under optimal line conditions.

In addition, the LEDs 109a to 109d are lit for two seconds at a time, and if a larger data error is detected during that time, they are immediately switched to the corresponding lamp display, so that the operator does not miss the display and always You will be able to know the maximum error value.

In the above embodiment, the reception error display unit 109 includes four LEDs 10 corresponding to the number of detected error bits.
9a to 109d are provided, but it goes without saying that the number of display units and display method can be arbitrarily set depending on the number of error bits that can be detected. Further, although each lighting time is set to 2 seconds, it goes without saying that this can also be set arbitrarily.

In addition, if a data error in the received image information cannot be corrected, the corresponding one line of the image is made blank, but as is done with known technology, the image of the same line as the previous line is It is also possible to record it or fill in that one line.

In addition, in the above embodiment, an error correction code is added to the image information and transmitted to display an error in the image information data, but an error correction code is added to the data of the procedure signal in transmission control and then transmitted However, errors in the procedure signal data can also be displayed in the same way.

Furthermore, the present invention is applicable not only to facsimile machines but also to various data transmission devices. For example, when applied to a data transmission device that uses a normal telephone line, if the line condition is poor, the system can make a call again, use a different line, or communicate at a different time. Data transmission becomes possible under better line conditions.

[Effects] As described above, according to the present invention, the number of data errors per fixed unit of received transmission data is detected and the display is performed based on the detected number of data errors.
The operator looks at the display during communication, determines whether the actual line condition is good or bad, and takes necessary measures, thereby making it possible to perform data transmission in the optimum line condition.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of a facsimile machine according to an embodiment of the present invention, FIG. 2 is a plan view of a reception error display section, FIG. 3 is a block diagram of the facsimile machine, and FIG. 4 is a reception error display. FIG. 5 is an operation flowchart showing image information reception processing, FIG. 6 is an operation flowchart of display processing, and FIG. 7 is an operation flowchart showing display restoration processing. 1 facsimile device, 2...interface device,
3. Wireless device, 4 Miter, 105a to 105c...
Operation buttons, 106a to 106c Status display lamps,
107 Document output slot, 109 Reception error display section,
109e-109h...Resistance, 109i-1091-
Nand element, 109m, 109n-inverter, 111
- Scanner, 112 Plotter, 113... Encoding/decoding unit, 114/Operation display unit, 115/Communication control unit, 1
16・Modem, 117...System control unit, 1098~
109d...LED. Figure 6 Figure 7

Claims (1)

[Claims] In a data transmission device having a function of correcting errors in transmission data transmitted with an error correction code added using the error correction code, a detection means for detecting the number of data errors per fixed unit of the received transmission data; , and display means for performing a display based on the detected number of data errors.