JPS60167068A - Recognition control system of bar code - Google Patents

Abstract

PURPOSE:To miniaturize a device and to reduce its cost by adopting a sequential control system to give a channel sequential circuit functioning as one common sequence circuit. CONSTITUTION:A ROM13 is a memory for storing control sequence, and controls output information by decision information outputted from a decision processing control part 5 and feedback information. A shift register 14 is to store temporariry the output information from the ROM13, consists of flip-flop circuits, and mounted in accordance with the number of control channels. An output of the shift register 14 is inputted into an address A0 or A2 of the ROM13 and to a binary decimal convertor circuit 15, and an address A3 of the ROM13 is formed by the output. The final character and a checked result of a center bar or a guide bar are inputted to an address A4. The decision processing control part 5 includes a channel counter and decides which channel has the ROM output information.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a bar code recognition control system that reduces the number of ICs used and simplifies the circuit.

(b) Background of the Technology The present invention relates to a barcode demodulation processing device, in particular, in which input signals other than barcodes, that is, circuit noise, noise such as printed characters, and a true barcode signal are input in chronological order. The present invention relates to a barcode recognition control system that allows immediate identification at the next stage.

Here, barcodes display a large amount of information consisting of numbers, alpha vents, etc. using characters consisting of a combination of bars (black bars) and spaces (white bars), and by arranging multiple pieces of these characters, necessary information can be obtained. is displayed.

A barcode system is a system in which a barcode is formed on the object to be processed by a method such as printing, and this is automatically read using an optical system.
(Point of 5ales) The system can be mentioned.

This system is based on countries and producers of food and miscellaneous goods.

Product identification codes and other information are displayed in barcodes, and the information is read and processed by computer for each product.

A rotating polygon mirror is used as an optical reading device, but it is being replaced by a laser beam scanning device (laser scanner) using a hologram due to its drawbacks such as a complicated and expensive drive mechanism.

Next, various barcode configurations and arrangement methods have been put into practical use depending on the purpose, including UPC and JAN.

Code systems to which the present invention is applicable, such as EAN, employ an arrangement method as shown in FIG.

In other words, at the front and rear of the arrayed barcode data are guide bars (representing the start and stop knobs).
GB) 1, and a center bar (CB) 2 is provided in the center, and four or six characters 3 are arranged between them.

That is, the guide bar 1 has unit widths of white and black.

It is represented by a combination of white and black reference bars, and the following character 3 is white with a width that is a positive multiple of the unit width.

It consists of a combination of two sets of black, white, and black bars, and the unit character length is determined to be seven times the standard bar, and one character or number is displayed by a combination of four bars with different widths. ing.

When the first half of the array consisting of 4 sets (or 6 sets) is completed, there is a center bar 2 consisting of an array of white, black, white, black reference bars, and then the 4 sets (or 6 sets) of characters. The array continues, and at the end there is a guide bar, completing the barcode configuration. .

Such barcode identification is performed by irradiating the barcode with laser light or projection light and detecting the intensity of the reflected light, but if there are confusing foreign objects such as other printed characters around the barcode, it may be difficult to identify the barcode. It is easy to get confused when reading barcodes.

The present invention relates to a recognition control method for optically detecting barcode data to discriminate and read true barcode data and erroneous data.

(c) Prior art and problems In the conventional barcode recognition control system, a sequential circuit with the same configuration is used as a means to distinguish between error data and true barcode data (signal).
Since each code system of N was equipped with only 4 channels, the circuit scale became large, and as a result, it was impossible to avoid increasing the size of the device.

FIG. 2 is a block diagram of a conventional control system.

Here, input information 4 obtained by reflection of scanning light such as a laser enters the determination processing control section 5, which has the following check circuit and performs sequential determination processing.

Check circuit for il+white margin length and guide bar (start/stop bar) length.

(2) First character length check circuit.

(3) Check circuit for second to fourth character lengths.

(4) Center bar (end character) length check circuit.

(5) Bar width size comparison circuit and code conversion circuit.

In other words, input information 4 is sequentially passed through the check circuits (]) to (4) above to determine whether it is correct information or incorrect information, but if it is correct information, the result is is processed in the channel I sequential circuit 6 of the four channel sequential circuits provided in parallel.

However, if the determination processing control unit 5 determines that the information is error information in the middle stage of the above (11 to (4) check circuits), the processing in the channel 1 sequential circuit 6 is cleared at that stage and the original state is returned. .

On the other hand, while error information is being processed in the channel 1 sequential circuit, the determination processing control unit 5 determines whether the white margin of the barcode and the guide bar (CB>1 or the center bar (C
B) 2 is detected and recognized as correct information, processing of this information is started in the channel 2 sequential circuit 7, and from then on the white margin and guide are similarly processed even though the first information is being processed. Bar 1 or center bar (CB>
If 2 is detected, channel 3 sequential circuit 8. Barcode information was processed by switching between channel 4 and sequential circuit 9 respectively.

Note that switching of the signals from the channel 1 sequential circuit 6 to the channel 4 sequential circuit 9 is performed by a pulse output from the common control section 10.

The correct barcode signal with error information removed in this way is processed by one of the four sequential circuits, passes through the multiplexer 11 operating under the control of the common control unit 10, and reaches the output port 12. There, it is sent as a data signal to the data bus together with the demodulated data processed by the determination processing control unit 5, and is passed to a data processing unit (not shown in FIG. 2) that processes the read data, where it is processed as product information. .

In conventional channel sequential circuits, in order to distinguish correct information from erroneous information, four sets of completely independent circuits with equal circuit configurations are required, which requires a large number of circuit elements and increases the size of the device. At the same time, an increase in costs could not be avoided.

(d) Purpose of the Invention The purpose of the present invention is to reduce the size of a barcode recognition control device that eliminates erroneous information from time-series input information and identifies and processes correct barcode signals. The object of the present invention is to provide a recognition control method that can reduce costs.

(e) Structure of the Invention The object of the present invention is to optically read and demodulate a barcode composed of two sets of white and black bars with different widths as unit characters, and a plurality of these characters arranged. In a barcode reading device, four sets of channel sequential circuits are used as one common sequential circuit to eliminate erroneous input signals other than barcodes and recognize only true barcode signals. A four-stage shift register is provided on the successive output side of the ROM to propagate the read output signal of the ROM using the white and black inflection points of the character as a trigger, and to transmit the output signal in time. This can be achieved by a barcode recognition control method characterized by sequentially feeding back as a ROM address input signal and performing multi-channel sequential control.

(f) Embodiments of the Invention The present invention utilizes the concept of a microprogram method in a sequential circuit that processes time-series independent data to provide a function as a common sequential control circuit. This will significantly reduce the scale.

In other words, the present invention requires sequential circuits for four channels in code systems such as JAN, EAN, and UPC, but in these circuits, as shown in FIG. The circuit is configured by taking advantage of the fact that the same channel is selected in each period, and by feeding back previous information to the sequential circuit according to the period in chronological order, it is possible to create a sequential circuit for four channels. A common sequential control circuit for one channel is sufficient.

FIG. 4 is a basic block diagram of the recognition control system according to the present invention, and Table 1 shows the relationship between ROM address input and ROM data output.

In FIG. 4, a ROM 13 is a memory that stores a control order, and controls output information based on the determination information and feed bank information output from the determination processing control section 5.

Here, shift register 1 existing on the output side of ROM 13
Reference numeral 4 denotes a register for temporarily storing the output information of the ROM 13, which is composed of a solid flop circuit and is equipped according to the number of control channels, and in this embodiment has a 3-bit configuration with 4 stages. The output of the shift register 14 is RO
It is input to the address AO to A2 terminals of M13 and the binary/IO base conversion circuit 15.

Next, the binary/decimal conversion circuit 15 converts the output signal of the shift register 14 into a decimal number, inputs this signal directly or via the OR gate 16 to the AND circuit 7, and combines it with the signal from the determination processing control section 5. After synchronization, it passes through the OR circuit 18 and becomes the address A3 of the ROM 13.

Then, the result of checking the final character and the center bar or guide bar is input to the address manual A4.

Further, the judgment processing control unit 5 has a channel counter, and R
Determine how many channels the OM output information belongs to.

Next, the output port 12 sends the demodulated data from the judgment processing control section 5 and the judgment result obtained from the ROM output together to the data bus line of the processing device.

The circuit operation according to the present invention will be specifically explained below.

The information from the determination processing control unit 5 is as described above (11
Check results for white margin and guide bar or center bar, (2) Check results for first character, (3)
The check results of the second to sixth characters, (4) the final character and the information of the check results of the center bar or guide bar are sent in chronological order, and are subjected to logical operations with the output of the binary-to-decimal conversion circuit 15 and stored in the ROM.] However, when checking the white margin of +11 and the guide bar or center bar, the A1 "response input is 0000 as shown in Table 1, and therefore the ROM 13 is input to the A3 terminal of ROM 13. The read data Do to D2 output is also 00.
0, and 1]0 to D2 are input to the shift register 14 and transferred. This is the initial state.

Next, when the bar information passes the white margin and guide bar check or center bar check, the output of the binary/decimal conversion circuit 15 indicates O, while the determination processing control unit 5
Since the output of indicates 1, the AND gate 17 opens and the ROM
As a result, the A3 manual power of 13 becomes 1, and as a result, the input becomes 1000, and 001 is output from the ROM 13. This is the first step.

Next, this information passes through a four-stage shift register 14 and is transferred to the RO
At the time of feedback to M 13, the first of (2)
If the character check passes, AO to A2 manual power is 001 and A3 manual power is 1, so the address input is 1001 and the data output of ROM13 is 01.
It becomes 0 and is output to the shift register 14. This is the second step.

Thereafter, the second character and the third character are checked in this way, and if it is determined that the information is incorrect during this process, the A3 manual power becomes 0, and as a result, the output of ROM 13 becomes all O, returning to the initial state again. Return to

On the other hand, if all the constituent characters of the barcode pass the check, the data output of the ROM 13 will be 1000, and the result of the determination of the end of the sequence will be output from the D3 terminal.

Note that Table 1 shows the case where the barcode consists of 6 characters, but in the case of 4 characters, if address A4 of ROM 13 is 1 at the time when the 5th character fails, that is, the final If the check between the character (4th character) and the center bar or guide bar passes, it is recognized as a barcode consisting of 4 characters, and the data output of ROM 13 is set to 100.
0, and the result of determining whether the sequence has ended is output from the D3 terminal.

With the above method, other channels can be similarly controlled in a time-series manner.

In this way, the sequential control circuits for four channels can be connected to a common one.
By using a sequential control circuit for each channel, the circuit scale can be significantly reduced.

(g) Effects of the Invention The present invention solves the problem that the conventional barcode recognition control device is equipped with multi-channel sequential circuits, which increases the size of the circuit. The circuit size is reduced by providing functions and using a sequential control method, and by implementing the present invention, bar code recognition control becomes easy, and the device can be made smaller and costs are reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the configuration of a barcode, FIG. 2 is a block diagram of a conventional recognition control system, FIG. 3 is an explanatory diagram of a character configuration, and IS4 is a diagram of j, Q! according to the present invention. 1I
11 is a block diagram of the No. 11 control system. FIG. In the figure, 1 is a guide bar, 2 is a center bar, 3 is a character, 5 is a judgment processing control unit, 6, 7, 8°9 are channel sequential circuits, 10 is a common control unit, and 13 is a ROM.
, 14 is a shift register, 15 is a binary/IO base conversion circuit,
16 and 18 are OR circuits, and 17 is an AND circuit. Qin 1 year 2 days

Claims (1)

[Claims] Errors other than barcodes are detected in barcode reading devices that optically read and demodulate barcodes made up of two sets of white and black bars with different widths, which are arranged as unit characters. eliminate the input signal,
Designed to recognize only true barcode signals 4
RO a set of channel sequential circuits as one common sequential circuit
M (read-only memory device), a four-stage shift register is provided on the read output side of the ROM, and the successive output signals of the ROM are propagated using the white and black inflection points of the character as triggers. Feedback the output signal in time series as a ROM address input signal,
A barcode recognition control method characterized by multi-channel sequential control.