GB2253293A - Bar code printer - Google Patents

Abstract

In a printer (2) capable of efficiently creating and printing bar code symbols in various versions thereof, the dot pattern is copied in the bar height direction by the number of rows required to print the bar code of the specified height. Typical patterns are predetermined and stored in a ROM (8). The printer (2) is capable of handling such bar codes as CODE 39 in which the patterns for different digits can be defined independently of each other, or such bar codes as ITF and WPC in which the pattern for each digit is defined according to prescribed rules. In case of WPC, when a flag code and the number of dots to form a minimum module are specified from an external device (1), a dot pattern for one row for each digit of a bar code is created and held within the printer, and when these conditions are not specified from the external device (1), predetermined values are adopted to create the dot pattern for each digit. <IMAGE>

Description

le 4 222 ' 2S.) ' BAR CODE PRINTER The present invention relates to a

printer having a bar code printing capability. and more particularly to abar code printer capable of printing bar codes at any desired bar ratio.

Bar codes can be classified into the following two major types.

The first major type is a bar code in which patterns are predetermined for individual characters. so that the bar code pattern for an array of characters can be created by just arranging the patterns assigned to the characters in the sequence of the characters. This means that the pattern for each digit can be determined independently of each other. This type of bar code is hereinafter referred to as type 1.

The second major type includes bar codes in which patterns for individual characters are not Predetermined by the rules unique to the applicable bar code symbology. In 1 this type, the pattern for each digit is dependent on the rules adopted and is therefore determined in a dependent manner. This major type includes a symbology in which two characters together, i.e. an odd- numbered digit and an even-numbered digit, are represented by one pattern. This kind of bar code is hereinafter referred to as type II.

The second major type further includes a bar code in which multiple kinds of patterns are assigned to each individual character in accordance with multiple kinds of character/pattern mapping tables provided. In this type, the country that uses the bar code selects the table to determine the patterns for individual digits. This kind of bar code is hereinafter referred to as type III.

Generally, in type I,-various values such as 3:1, 8:3, 5:2 and 2:1 are used for the wide bar width to narrow bar width ratio (hereinafter also referred to simply as the. ratio) in the bar code. The ratio is fixed or variable depending on the kind of bar code employed. In either cAse, when printing a bar code at a desired ratio, the ratio must always be specified, and other complicated processes are also required.

Furthermore, it is usual with this type to create a bar code pattern after receiving a print command, and it takes a considerably long processing time to print the bar code than printing ordinary characters.

Type II includes such bar code symbologies as the ITF (Interleaved Two of Five) bar code. In this bar code, five odd-numbered-digit bars (dark elements) and five evennumbered-digit spaces (light elements) adjacent to the respective bars are used in combination, each set of elements representing one character. In five elements of each set, two elements are wide and three are narrow.

Printing the ITF bar code involves the various problems as described below.

A) In one method, patterns for 11011 to 11911 are individually predetermined, and the odd-numbered digits and even-numbered digits are combined in pairs when printing. However, if the number of digits is large, editing for pairing the digits takes a considerable time; in some cases, it can take ten times longer than when printing an ordinary bar code.

B) In another method in which patterns for "0V to '19911 are predetermined eliminating the need for pairing the oddnumbered digits and even-numbered digits when printing, this means 100 different patters have been already prepared, and therefore, the contents of the bar code cannot be directly entered from the keyboard to produce the required pattern.

C) In almost all cases, neither A) nor B) provides arrangements that allow the wide to narrow ratio to be set at a desired value.

Type III includes such bar code symbologies as the WPC (World Produce Code) bar code.

In some conventional printers designed to print WPC bar codes, the origin of country (the code used in Japan is JAN code provided for by JIS-B9550), magnification ratio, etc, are fixed, and in others, edit processing for mapping key entries into the bar code characters to be printed is performed using software of external device.

According to the present invention there is provided a bar code printer comprising:

means for storing a bar code pattern for one row in the form of bits or codes; and means for copying the bar code pattern in the bar height direction by the required number of rows to print the bar code.

Embodiments of the present invention can provide a bar code printer capable of printing bar codes in a simple and speedy manner without requiring complicated processes.

The invention can also provide a bar code printer capable of creating and printing ITF bar codes, etc. in an efficient manner.

Conventional printers designed to print WPC bar codes have disadvantages that the country of origin, magnification ratio, etc. are fixed and cannot be changed as desired and that mapping key entries to the bar code characters to be printed cannot be achieved without depending on software of external device.

Embodiments of the invention can provide a bar code printer capable of printing WPC bar codest etc. of any desired flag at any desired magnification ratio.

Embodiments. of the invention can provide a bar code printer that allows selection between a standard version and a shorter version symbol representation as desired.

Embodiments - of the invention can provide a bar code printer capable of printing these bar codes in an efficient manner.

In some embodiments of the invention, there is provided a printer having a bar code printing capability, wherein, for bar codes of type I in which individual character patterns are defined independently of adjacent characters, patterns of typical dimensions (density) are stored, for example, in a ROM, in the form of bit patterns each for one row, and selected one-row bit patterns are copied in the bar height direction by an n number of rows required to produce a bar code of the desired height. The printer further includes means for registering optional bar code patterns of two or more systems in encoded form in a RAM or the like in order to print bar codes of the above type but of other dimensions than the typical dimensions. The printer also includes means for automatically expanding the codes to one-row bit patterns upon power-on and for storing the bit patterns thus expanded.

For bar codes of the type in which individual character patterns are defined independently of adjacent characters, the character patterns of the typical dimensions are permanently contained in the ROM in the form of bit patterns each for one row, and required dot patterns are read out in accordance with print commands to construct a bit pattern extending along the entire length of the bar code; the thus constructed bit pattern is then copied in the bar height direction by the required number of dots, thus producIng the desired bar code in a simple and speedy manner.

For bar codes of the same type but of dimension ratios not stored in the ROM, character patterns of optional dimension ratios are stored in memory in encoded form; when power is turned on, the encoded character patterns are expanded to bit patterns and stored in memory, from which required bit patterns are selected in accordance with print commands, thus enabling the desired bar code to be promptly created for printing.

According to certain embodiments of the invention, 1) For the bar codes of the type in which individual character patterns are defined independently of adjacent characters, since typical bit patterns are permanently stored internally, there is no need to specify the wide bar to narrow bar ratio at each printing; from the one-row patterns already created and registered, required patterns 0 are selected and copied in the bar height direction to produce a bar code of the desired height, thus eliminating the need for complicated processing for printing.

2) For bar codes of other dimension ratios, since bit patterns are automatically created when power is turned on, no complicated processing is necessary for printing.

I n other embodilments of the invention, there is provided a bar code printer wherein for bar codes of type II, dot patterns of a plurality of combinations, preferably 1.00 combinations representing the numbers from 10011 to 1f999f, each for one row, are created and stored internally, each combination representing two characters together, one being constructed of a prescribed number of odd-numbered bars preceded by a start code and the other being constructed of the same number of spaces adjacent to the respective bars in interleaving fashion, so that required combinations of the dot patterns are sequentially selected according to the supplied information on the bar code to be printed, thereby constructing a bar code pattern for one row extending along the entire length of the bar code.

According to such embodiments of the invention, the bar code printer is also constructed in such a manner that: when the number of dots to form a narrow element and a wide element is specified from an external device, a dot pattern for the start code and the 100 different dot patterns for the two- 1 digit numbers from "0011 to "9911 are automatically created for one row and stored into an internal memory of the printer and then, a one-row pattern for an ITF bar code or the like is constructed by connecting, in blocks of two digits, an even number of digits entered from the external device or from a keyboard on the external device with the stored patterns; when the number of dots for either the narrow or the wide element is not specified from the external device, the number of dots for both of narrorw and wide element predetermined and stored internally within the printer is automatically adopted for each element, to create the bar code pattern in ITF or the like; and the one-row bar code pattern is copied in the bar height direction by the required number of rows to print the ITF bar code or the like of the specified height.

In some embodiments of the invention, dot patterns of a plurality of combinations, each for one row, are created and stored internally, each combination representing two characters together, one being constructed of a prescribed number of odd-numbered bars preceded by a start code and the other being constructed of the same number of spaces adjacent to the respective bars in interleaving fashion, so that required combinations of the dot patterns are sequentially selected according to the supplied information on the bar code to be printed, thereby constructing a bar code pattern 8 - for one row extending along the entire length of the bar code. This configuration of the invention permits effective creation of the desired ITF bar code or other bar code.

Optionally, according to the invention, the number of dots for the narrow and wide elements, which is essential for dot pattern formation, is determined in such a manner that when the number of dots is specified externally, the externally specified value is adopted, and when the value is not specified externally, the number of dots predetermined and stored internally within the printer is adopted, to print the above-said twodigit dot patterns, thus enabling the standard dot or optional dot configurations to be selected as desired to suit particular application requirements.

As is apparent from the above description, the invention can offer the following advantages.

3) Complicated ITF bar codes and other bar codes can be created and printed in a simple manner in correspondence with keyboard entry.

4) The ratio of "wide" bar to "narrow" bar can be set at any desired value so that any particular application requirements can be dealt with promptly.

In a further embodiment of the invention, there is provided a bar code printer wherein when printing a bar code of type III, especially a WPC bar code, the dot patterns for the left guard bar, center bar, right guard bar, and the bit 1 patterns of characters in the bar code can be edited internally within the printer on the basis of the information on the flag code and the minimum module (the number of dots per module, etc.) received from an external device or on the basis of the predetermined values for the flag code and the minimum module, thereby enabling the WPC bar code, etc. of any flag code to be printed at any magnification ratio in either a standard version or a shorter version representation as desired.

With certain embodiments of the invention, the bit patterns for the left guard bar, centre bar, right guard bar, and the bit patterns of characters in the bar code are created and held internally within the printer on the basis of the information on the flag code and the minimum module supplied from the external device or predetermined internally, thereby providing the printing capability to print WPC bar codes, etc. of any flag at any magnification ratio in either the standard or shorter version representation as desired.

Thus, according to such embodiments of the invention, WPC bar codes of any flag can be printed at any desired magnification ratio by performing keyboard entry corresponding to the character in each digit of the WPC bar code.

Furthermore, since bar codes of any type can be printed at any desired ratio, it is possible to adjust the bar code length to match particular needs for designing a label, etc. containing the bar code.

The present invention will be further described hereinafter with reference to the following detailed description and the accompanying drawings, in which:

Fig.1 is a schematic diagram illustrating the system configuration of a bar code printer according to one. embodiment of the invention; Fig.2 shows a representation of a bar code of type I for which the bar code printer of Fig.1 is intended; Fig.3 shows examples of dot expansion for one row of the bar code of Fig. 2; Fig.4 is a diagram illustrating the format in which a bar code pattern for one row is stored in a ROM in the system of Fig.1; Fig.5 is a diagram illustrating the format in which bit pattern for one row of a bar code is stored in a RAM in the system of Fig.1; Fig.6 is a program flow chart for the general operation of the bar code printer of Fig.1; Fig.7 is a schematic diagram illustrating the system configuration of a bar code printer according to another embodiment of the invention; - 11 1 Fig.8 shows an example of a print program flow chart in the bar code printer of Fig-7; Fig.9 illustrates examples of commands that the bar code printer of Fig.7 receives from an external device; Fig.10 is a diagram illustrating the format of information which is stored in a RAM in the system of Fig.7; Fig.11 is a diagram illustrating how an ITF bar code pattern, i.e. type II, is constructed in the system of Fig.7; Fig.12 is a table showing ITF bar code pattern configuration; Fig.13 is a schematic diagram illustrating the system configuration of a bar code printer in a further embodiment of the invention; Fig-14 shows an example of a program flow chart for creating and printing a WPC bar code, of type III, in the embodiment of Fig.13; Fig.15 shows an example of the bar code creation command that the bar code printer of Fig.13 receives from an external device; Fig.16 illustrates an example of a bar code pattern created by the bar code printer of Fig.13 and the format in which the information on the bar code pattern is stored in a RAM; Fig.17 shows an example of the print command that the printer of this invention receives from an external device; Fig.18 is a diagram showing a module configuration of a standard version WPC bar code; Fig.19 is a diagram showing a module configuration of a shorter version WPC bar code; Fig.20 is a specific example of a WPC bar code symbol structure; Fig.21 is a table showing WPC bar code pattern configuration; Fig.22 is a table of flag assignments in WPC bar code; Fig.23 illustrates a method of calculating a cheek digit in a WPC bar code; Fig.24 is a schematic diagram illustrating a system configuration of a still further embodiment of the invention; Fig.25 shows the contents of a RAM area 12 for bar code in the system of Fig.24; and Fig.26 shows the contents of a ROM area 8 for bar code in the system of Fig.25.

The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Fig.1 is a schematic diagram illustrating the system configuration of a bar code printer according to one embodiment of the invention. In Fig.1, an external device 1 such as a personal computer is shown as well as a bar code printer 2. The bar code printer 2 includes a bus 3, an input/output interface 4, a CPU 5, and ROMs 6 - 8. The ROM 6, the first ROM, is for generating character patterns, and the ROM 7, the second ROM, contains data editing programs, print control programs, etc. The ROM 7 also contains the program shown in Fig.6 for the general operation of the printer.

The ROM 8, the third ROM, contains patterns for designated bar codes of type I such as CODE 39 and NW-7; more specifically, individual alphanumeric character patterns of typical dimension ratios are stored in the form of bit patterns each for one row (examples shown in Fig.3), and the designated bar codes are assigned, for example, code numbers 1 to 7. When printing a particular bar code, the required patterns are quickly read out using the code number and other information so that the desired bar code can be created promptly.

The bar code printer 2 also includes a RAM 9 for storing various kinds of print information and other data. The RAM 9 is divided into five areas 10 to 14. The area 10 is a print information storage area for storing such print information as print formats, print data per page, etc.

area 11 is an external character storage area for storing optional characters, etc. The area 12 is an optional bar code storage area for storing one-row patterns of characters other than those of typical dimensions contained in the ROM 8. The area 12 is subdivided into a code pattern storage area 12a and a bit pattern storage area 12b. The patterns are stored for bar codes of various kinds, as required (for example, bar code numbers 8 and higher), and are selected as specified when printing. The bar code patterns stored in the optional bar code storage area 12 can be replaced by other patterns, or additional patterns can be added, as required. The area 13 is an input buffer for temporarily storing the print information of code pattern received from the external device 1. The area 14 is an output buffer into which print information expanded to bit patterns is sequentially read for printing, and a print head 15 is controlled by the print control programs stored in the second ROM 7.

For the RAM 9, a battery 16 or the like is provided so that its contents can be retained after the main power supply is cut off.

Among the types of bar code, type I can be classified as an independent type wherein individual bar code character patterns are defined independently of adjacent characters, and type II and type III as a dependent type - 1 wherein each individual character pattern cannot be defined by itself but depends on adjacent characters.

In type I, the shape and dimensions of bar code are determined by the number of dots assigned to each of the wide dark element M), narrow dark element (NB), wide light element (WS), and narrow light element (NS), and the size of one dot. These parameters vary from one bar code symbol to another.

CODE 39, which is currently most widely used, and NW-7, which was once widely used, are typical examples of this type of bar code. MSI, 2 of 5, and CODE 27 also belong to this type of bar code.

As an example, a representation of '15" in CODE 39 is illustrated in Fig. 2.

In CODE 39, typical dot assignments for the respective elements are as follows:

WB = 5 dots (625gm) NB = 2 dots (25Ogm) WS = 5 dots (6251Am) NS = 2 dots (250,gm) GAP = 2 dots (250pm) With the above dot assignments, "511 in CODE 39 is represented by an array of 29 effective dots, "V's and 9'0"s, as shown in Fig.3(a). This converts to F983E660 in hexadecimal notation.

r As shown, a typical pattern in CODE 39 has a dot ratio of N:W:G = 2:5:2, where N is the number of dots for the narrow element, W is the number of dots for the wide element, and G is the number of dots for the gap. This pattern is stored, for example, under the bar code number 3 in the ROM 6.

On the other hand, a typical pattern in NW7 has a dot ratio of N:W:G = 2:6:6. This pattern is stored, for example, under the bar code number 4 in the ROM 6. T.o print patterns in MSI, 2 of 5, CODE 27, etc., a typical dot pattern for each is to be registered as an optional bar code in the RAM 12.

Thus, other patterns than the typical patterns for CODE 39 and NW7 or patterns for other bar code formats in type I can be stored in the RAM 12 with any desired dot assignments. The patterns stored in the RAM 12 can be handled in the same manner as those contained in the ROM 6. The optional bar codes are registered, for example, under the bar code numbers 8 and 9, so that each bar code can be handled as an independent one.

Fig.3(b) shows a code assignment with a different ratio than that of the typical pattern.

Suppose that a bar code format whose typical pattern is stored in the ROM 6 is to be printed with different dot assignments, for example, 8 dots for WB, 8 dots for WS, 3 1 dots for NB, 3 dots for NS, and 3 dots for GAP. With these dot assignments, 11511 in CODE 39 will be represented as shown in Fig.3(b), i. e. by an array of 45 effective dots which converts to FF1C03FC71D0 in hexadecimal notation.

Figs.4 and 5 respectively show the format of print information stored in the third ROM 8 and the optional bar code storage area 12 of the RAM 9 according to the system of Fig.l. As in Figs.2 and 3, 11511 in CODE 39 is taken as an example.

A) In the ROM 8, the print information is stored in the form of a bit pattern as shown in Fig.4. For printing, the address at which the memory is to be read is determined according to the kind of bar code specified, and the bit pattern for each of the alphanumeric characters constituting the bar code is read out. The thus readout patterns are constructed into a bit pattern extending along the entire length of the bar code, and the bit pattern is copied the required number of times in the bar height direction to produce the desired bar code. IIESC" indicates the escape code represented by hexadecimal 1B in ASCII code representation.

B) In the optional bar code storage area 12 where other bar code patterns for type I than the typical patterns are stored, the number of effective bits and a pattern for one row are registered for each code, as shown in Fig.5, according to the kind of bar code. The one-row pattern is not a bit pattern but in encoded form as shown.

When power is turned on to the printer, each one-row code pattern is expanded to a bit pattern and stored in the area 12. For printing, the address at which the memory is to be read is determined according to the specified kind of bar code and the height thereof, and the readout bit patterns for the alphanumeric characters are constructed into a pattern extending along the entire length of the bar code. This pattern is copied in the bar height direction as many times as required to produce the desired bar code.

Fig.6 illustrates a program flow for the general operation of the bar code printer of Fig.l. The following describes the outline of the program flow.

a) In steps al to a3, power is turned on and it is determined whether the bar code number 8 or 9 is already registered in the RAM area 12.

b) If any bar code is already registered in the RAM area 12, the bar code registered in the RAM area is expanded to a dot pattern in step a4 and stored into the area 12b, and when a print command is given, the specified bar code is printed in step a5.

c) If there are no bar codes previously registered in the RAM area 12, it is determined in step a6 whether any bar code is registered in the RAM area 12 after power on. If 1 a yes, then the registered bar code is expanded to a bit pattern in step a4 and is stored into the area 12b, and in step a5, the specified bar code is printed according to the print command.

d) If no bar codes are registered in the RAM area 12 after power on, the process proceeds to step a7. If the bar code specified for printing is contained in the ROM area 8 (bar code number other than 8 and g), the bar code is printed in step a5 when the print command is given. - e) If the bar code specified for printing is not contained in the ROM area 8, it is determined in step a8 whether any bar code contained in the ROM area 8 should be substituted. A switch for selecting the decision may be provided and may be preset to YES or NO, or the decision may be made interactively when it is determined that the bar code specified is not contained in the ROM area 8.

f) If it is determined to substitute the bar code contained in the ROM area 8, the specified bar code is printed in step a5 when the print command is given.

g) If it is determined not to substitute any bar code contained in the ROM area 8, error processing is performed in step ag as the specified bar code is not registered.

h) The processing is terminated in step a10.

Fig.7 is a schematic diagram illustrating the system configuration of a bar code printer according to another 1 embodiment of the invention. In Fig.7, an external device 1 such as a personal computer is shown as well as a bar code printer 2. The bar code printer 2 has a system bus 3 to which are connected such units as a CPU 5 and an input/output interface 4 through which print information is directly entered from a keyboard or is transferred from the external device 1.

The numerals 6, 7, and 8 designate a first, a second, and a third fixed memory, respectively, each construc'ted from a ROM or the like. The first fixed memory 6 is for character generation and used for printing, under the bottom of a bar code, footnote characters corresponding to the data characters in the bar code. The fixed memory 6 contains routine programs for generating characters, symbols, etc. of various styles and sizes as in an ordinary printer.

The second fixed memory 7 contains control programs including control programs for printing characters as an ordinary printer.

The third fixed memory 8 contains control programs for printing ITF bar codes, etc. The control programs include the program the flow of which is hereinafter described with reference to Fig.8 and other programs for various processes necessary for printing ITF bar codes.

A read-write memory 9 for storing other print patterns and print information is constructed, for example, from a 1 RAM. The RAM 9 has an input buffer area 13 for storing code type print information (including commands) received through the input/output interface 4 from the external device 1, a print information storage area 10 for storing print formats, an external character storage area 11, an ITF bar code storage area 12 which constitutes an essential part of this invention, and an output buffer area 14 for storing print information expanded to dot patterns for printing. Thus the hardware configuration of this embodiment is analogous to that of the foregoing embodiment illustrated in Fig.l.

ITF is an abreviation for Interleaved Two of Five in which the oddnumbered digits are constructed only of the bars and the even-numbered digits are constructed only of the spaces, five bars and five spaces being interleaved together to form a pattern representing two digits. Therefore, there is no need to provide a gap between patterns of adjacent digits.

In addition to general information on the ITF bar code, the standard or most frequently used dot count values (hereinafter called the standard values) for the ITF bar code, for example, N = 3 and W = 9 (N for the narrow element and W for the wide element), are stored under the bar code number 5 in the ITF car code information storage area 13. It is preferable to construct the system so that these values can be altered as desired by keying in new values to the external device I and transferring them to theprinter 2 or by entering new values directly to the printer 2 from the keyboard.

The storage area 13 also stores such data as the dot count values (e.g., N = 2, W = 6) received from the external device 1, the start and stop codes of the ITF bar code, and 100 different patterns for the two-digits numbers "00" to "99" created based on the specified dot counts.

If necessary, the 100 different two-digit unit dot patterns may be created beforehand based on the aforementioned standard dot counts and stored in the storage area 13.

Referring now to Fig.8, the following describes how the bar code is produced in this embodiment.

A) In steps bl to b2, the printer 2 is set ready to receive information from the external device 1. When print information is received in encoded form from the external device 1, the information in that encoded form is stored into the input buffer 10 of the RAM 9. To print ordinary characters or the like, the print contents are expanded to dots in the output buffer 14 by a page-by-page basis or in blocks of a suitable number of lines, the thus expanded dot patterns being sequentially output for printing.

B) To print a bar code, commands such as shown in Fig. 9 are given from the host computer 1 when setting the dot - 23 counts or when starting the print operation. When the dot counts are given, the 100 different two-digit unit dot patterns are promptly created and stored in the RAM g.

C) When the printer is started in bar code print mode, the number of dots (dot count) to form the narrow and wide elements is determined. That is, in step b3, it is determined whether the number of dots is already given before power on. If yes, since the dot patterns are already stored in the RAM 9, it is decided to adopt these dot patterns and the process proceeds to E) below.

If the number of dots to form the narrow and wide elements is not given yet, it is determined in step b4 whether the number of dots is given thereafter (after power on), and the following processing is performed according to the result.

a) If the narrow dot count N and the wide dot count W are given from the external device, these values, for example, N = 2 and W = 6, are set in step b5.

b) If no values are given from the external device, the values internally stored in the printer, for example, N = 3 and W = 9, are adopted and set in step U.

D) In step b7, based on the condition determined in the above C), the start and stop codes of the ITF bar code and the two-digit unit dot patterns for one row are stored in the RAM 9 (storage area 13). Fig.10 shows the information - 24 as stored in the RAM 9 when the dot counts, N = 2 and W = 6, are specified from the external device. As shown, at respective addresses in the RAM 9, the narrow dot count, the wide dot count, the start code, and the stop code are stored along with the two-digit unit dot patterns for 110011, 110111,...' 119811, 1199", each with effective dot count. Codes such as CC, FCC, etc. are hexadecimal codes.

In the lower part of Fig.10, a one-row pattern for 110111 is shown as an example. This pattern is constructed.by combining an odd-numbered digit pattern for "0" and an even-numbered digit pattern for "I", as shown in Fig.11.

Fig.11 shows an example of how a two-digit unit dot pattern is constructed. In the example shown, the elements of the odd-numbered digit pattern for 11011 are interleaved alternately with the elements of the even-numbered digit pattern for 111" to form the pattern for "Ol". Fig.12 shows a pattern assignment table.

E) In step b8, it is determined whether the information on the bar code height and the print contents are given. When these are given, the process proceeds to step b9, where the concatenated one-row patterns are copied the required number of times in the bar height direction and expanded in the output buffer 14 to produce the desired bar code.

The narrow and wide dot counts on the basis of which the bar code is produced can be set to any desired values by keying in the values to the host computer 1 and transferring them to the printer 2 or by entering the values directly to the print-er 2 from the keyboard. The bar code print contents and the height of the bar code to be printed can also be entered to the printer through the host computer or directly from the keyboard. In accordance with the thus entered information, the required patterns are selected in the specified order from the 100 two-digit unit patterns '100" to "99" stored in the RAM 9, to construct a one.row pattern extending along the entire length of the bar code, the one-row pattern then being copied the required number of times to produce the desired bar code dot pattern. Any desired ITF bar code can thus be produced efficiently by entering the required values from the keyboard.

It will be appreciated that various modifications may be made to the configuration of this embodiment. For example, for the standard dot counts for the narrow and wide elements stored internally in the printer, the 100 different two-digit unit dot patterns 110011 to 119911 may be created beforehand for storage in the RAM 9. In such configuration, if no specification of the dot counts is given from the external device, the bar code pattern for one row can be created promptly when the bar code print contents and the height of the bar code are given. This serves to further speed up the bar code printing process.

- 26 Fig.13 is a schematic diagram illustrating the system configuration of a bar code printer according to a further embodiment of the invention. In Fig.13, an external device 1 such as a personal computer is shown as well as a bar code printer 2. The bar code printer 2 has a system bus 3 to which are connected a CPU 5 and an input/output interface 4 through which print information is transferred from the external device 1. The numerals 6, first, a second, and a third fixed 7, and 8 designate a memory, respectively, each constructed from a ROM or the like. The first fixed memory 6 is for character generation and contains routine programs for generating characters, symbols, etc. of various styles and sizes as in an ordinary printer.

The second fixed memory 7 contains control programs including basic print control programs for printing characters, etc. as an ordinary printer, for example, a data editing program, a paper feed program, a print head control program, etc.

The third fixed memory 8 contains control programs for printing WPC bar codes, etc. The control programs include the program the flow of which is hereinafter described with reference to Fig.14, programs for performing the processes shown in Figs.15 to 17, and other programs for performing various processes according to various rules, hereinafter described, necessary for printing WPC bar codes.

4 A read-write memory for storing other print patterns and print information is constructed, for example, from a RAM 9. The RAM 9 has a print information storage area 10 for storing print formats and other print information, an external character pattern storage area 11 for storing optional characters, etc., a WPC bar code information storage area 12, an input buffer 13 for temporarily storing code print information entered through the input/output interface 4, and an output buffer 14 for storing patterns for all digits to supply to the print head. The storage area 11 also stores patterns of OCR-B font for printing, under the bottom of a bar code, characters corresponding to the data characters and modular check characters in the bar code. The memory contents of the RAM 9, such as, the format information, etc. stored in the area 10, the external character information, etc. stored in the area 11, and the WPC bar code information stored in the area 12, can be altered, or supplemented with additional data, as desired by keying in new values to the external device 1 and transferring them to the printer 2 or by entering new values to the printer 2 directly from the keyboard. A memory backup feature using a battery 6 or the like is provided so that the entire contents of the RAM 9, especially the contents of the areas 10 - 12, can be retained after the main power is cut off. The WPC bar code information storage p i area 12 stores the flag. module. and one-row pattern. A thermalhead or other type of print head 15 is used for printing.

Referring now to Figs.18 - 23. the rules for Printing WPC bar codes will be described below. WPC is an abreviation for World Product Code.

A standard version WPC symbol (Fig.18) consists of a left guard bar 31. a six-character lefthand character 32. a center bar 33, a five-character righthand character 34'. a check digit 35. a right guard bar 36. and a left edge and a right edge margin (white space) of a minimum width of the combined widths of seven modules. In this embodiment. the bar code number 6 is assigned to this type of bar code symbol.

A shorter version WPC symbol (Fig.19) consists of a left guard bar 41. a four-character lefthand character 42. a center bar 43. a three-character righthand character 44, a check digit 45, a right guard bar 46, and a left edge and a right edge margin of a minimum width of the combined widths of seven modules. In this embodiment. the bar code number 7 is assigned to this type of bar code symbol.

in the standard WPC version, a separate digit called a flag to identify the country of origin is Provided preceding the items 32. 34, and 35 in Fig.18, but the flag digit 51 is not printed in the form of bars (Fig.20). Bars of four different widths are used. and the bar of the smallest width 4 is called the m-inimum module M by which the other three widths are automatically determined.

In WPC. three tables called SET-A. SET-B, and SET-C are provided for the ten digits "0" to "9" (three patterns for each digit) as shown in Fig.21. Selection of the Pattern assignment table for each digit in a bar code depends on the selection of the flag M that indicates the country of origin. In the standard WPC version. a representation of the flag will be as described below.

For example, when 114" is set as the flag. the six-characters in the lefthand character (32 in Fig.18) are respectively made to correspond to the table sets A. B. A, A, B. B in this order from left to right (see Fig. 22). In WPC. the flag "411 indicates that the code is the Japanese Article Number (JAN) adopted in Japan and provided for by JIS-B9550. When the flag is "0". the code is the Universal Product Code (UPC) adopted in the U.S.A.

In the standard WPC version. the five characters in the righthand character (34 in Fig.18) and the check digit (35 in Fig.18) are all represented using the Pattern assignments of SET-C.

In the shorter WPC version. the flag is also represented by a printed bar Pattern and included in the four-character lefthand character (42 in Fig. 19).

In the shorter WPC version. the four characters in - 30 lefthand character (42 in Fig.19) are all represented using the Pattern assignments of SET-A (Fig.21). while the three characters in the righthand character (44 in Fig.19) and the check digit (45 in Fig-19) are all represented using the Pattern assignments of SET-C (Fig.21).

The check digit in the standard WPC version is calculated as illustrated in Fig.23.

The check digit in the shorter WPC version can be calculated by substituting 11011 for the high-order fiv45 digits (character positions 9 to 13) in Fig.23.

The above has described the rules for printing WPC bar codes. These rules are controlled by the third ROM 8 for WPC bar code Print control, and the edited patterns in each set and the dot Patterns of the right and left guide bars and center bar are stored in the RAM 9 for one row.

Based on the bar code height information. the full digit Pattern is copied the required number of times in the bar height direction, and the thus created pattern is stored in the output buffer 14 for printing.

When no information on the flag and minimum module dot count is transferred from the external device, the following values. for example, are automatically adopted as the typical pattern. based on which the bar code dot pattern is created.

Flag "411 .. Indicates Japan.

- 31 Minimum module "3"... Closest to the typical size when printed using an 8 dots/mm print head. (1.14 times the typical size) The flag value, minimum module dot count, etc. are contained in the WPC bar code information storage area 12. These values can be supplemented with additional data or altered as required. When the information is altered, the contents of the RAM 9 relating to the bar code number 6 or 7 will also be altered accordingly.

Referring now to the flowchart of Fig.14, the operation of the bar code printer of this embodiment will be described below.

A) In steps cl to c2, the printer is set ready to receive information from the external device 1. The print information, including commands, transferred from the external device 1 in encoded form is stored in that encoded form in the input buffer 13.

The commands specify the flag setting and the minimum module dot count, as shown in Fig.15, but in some cases, these values are not specified. (When these two values are specified, the print contents are expanded to dots.) B) When the printer is started for printing, it is determined in step c3 whether the flag and the minimum module are already given before power on. If they are not given, it is determined in step c4 whether these two values have been given from the external device after power on. If these values have been given from the external device, the specified flag and minimum module are set in step c5; if they are not given eventually, the internally preset values, for example, 4 for the flag and 3 for the minimum module, are automatically adopted in step c6.

C) In step c7, based on the values set in the above B), each pattern of the WPC bar code is expanded to dots for one row and stored in the area 12 of the RAM 9 as shown in Fig.16, for example.

D) Next, in step c8, it is determined whether the print contents and the bar code height information are given. When these are given, the check digit is calcutated in step cg, and the check digit bit pattern is appended and stored in the same manner as described in the above C).

E) In step c10, based on the bar code height information, the required number of rows are added and expanded in the output buffer for printing.

F) In the above process C), the standard version or the shorter version is already specified by an external command (see Fig.17), in accordance with which SET-A, SET-13, or SET-C (see Figs.21, 22) is selected for each digit of the bar code. Each pattern is expanded to dots based on this selection. Thus, the standard version or the shorter version can be selected as desired by a command, etc. to a f print a bar code in the desired version.

Fig.24 is a schematic diagram illustrating a system configuration of a bar code printer according to a still further embodiment of the invention. According to this embodiment, any bar code, type 1, type II, or type III, can be printed. To achieve this, data such as shown in Fig-25 is stored in a bar code RAM area 12 of a RAM 9. A ROM 8 contains data and programs as shown in Fig.26. The operation for printing the bar code of each type is the same as in the foregoing embodiments of Figs.1, 7, and 13.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

34 - k

Claims (22)

1. A bar code printer comprising:

means for storing a bar code pattern for one row in the form of bits or codes; and means for copying the bar code pattern in the bar height direction by the required number of rows to print the bar code.

2. A bar code printer as claimed in claim 1, wherein the storing means stores one row of bar code in which individual character patterns in a bar code are defined independently of adjacent characters, as bit patterns of typical density.

3. A bar code printer as claimed in claim 1 or 2, further comprising means for storing optional bar code patterns of two or more systems in encoded form.

4. A bar code printer as claimed in claim 3, wherein the optional bar code patterns are of different densities from the typical density.

5. A bar code printer as claimed in claim 3 or 4, further comprising means for automatically expanding the codes to one-row bit patterns when power is turned on and for storing the bit patterns.

6. A bar code printer as claimed in claim 1 or 2. further comprising means for expanding codes of an optional bar ratio to one-row bit patterns and for storing the bit patterns.

7. A bar code printer as claimed in claim 5 or 6, wherein the optional bar code patterns are retained after power of the printer is turned offi

8. A bar code printer comprising:

means for creating and storing dot Patterns in a plurality of combinations, each combination representing two 36 characters. one being constructed of a prescribed number of odd- numbered bars preceded by a start code and the other being constructed of the same number of spaces adjacent to the respective bars in interleaving fashion; and means for forming a bar code pattern for one row extending along the entire length thereof by sequentially selecting combinations of the dot patterns according to the supplied information on the bar code to be printed.

9. A bar code printer as claimed in claim 8, wherein, when the number of dots to form a narrow element and a wide element is provided from an external device, the bar code pattern forming means creates automatically a dot pattern for the start code and 100 different dot patterns for twodigit units from 110011 to 919919, stores the thus created patterns into an internal memory of the printer, and constructs an ITF bar code by connecting, in blocks of two digits, an even number of digits entered from the external device or from a keyboard on the external device with the stored patterns.

10. A bar code printer as claimed in claim 8 or 9, wherein, when the number of dots for either the narrow or the wide element is not specified from the external device, the bar code pattern forming means automatically adopts values predetermined for the respective elements.

11. A bar code printer as claimed in claim 10, further comprising means for altering the set values for the narrow and wide elements.

12. A bar code printer as claimed in claim 8, 9, 10 or 11 wherein, when the height of the bar code is specified from the external device, the bar code pattern forming means copies - 37 the bar code pattern in the bar height direction by the required number of rows to print the bar code of the specified height.

13. A bar code printer as claimed in any one of claims 8 to 12. further comprising memory backup means for retaining, after power is turned off to the printer, information on the number of dots for the narrow and wide elements specified from the external device and the dot patterns expanded in accordance with the specified number of dots and stored in the internal memory.

14. A bar code printer comprising:

means for internally creating dot patterns to represent one row for each digit of a bar code when a flag code and the number of dots for a minimum module are specified from an external device; and means for holding the thus created dot patterns.

15. A bar code printer as claimed in claim 14, further comprising means which, when the height of the bar code is specified from the external device, copies each one-row dot pattern in the bar height direction by the required number of rows to produce the bar code of the specified height.

16. A bar code printer as claimed in claim 14 or 15, further comprising means which, when the flag code and the number of dots for the minimum module are not specified from the external device. automatically adopts values predetermined for the flag code and the minimum module.

17. A bar code printer as claimed in claim 14, 15 or 16, further comprising means for altering the set values for the flag code and the number of dots for the minimum module.

18. A bar code printer as claimed in claim 14, 15, 16 or 17 further comprising means for performing control so that, when the flag code and the number of dots for the minimum module are specified from the external device, the values thus specified are adopted to create the bar code, and so that, when these values are not specified from the external device, a dot pattern for one row for each digit of the WPC bar code, including a left guard, a centre bar, a right guard bar, and a check digit, is created and held within the printer in accordance with values predetermined for the flag code and the minimum module.

19. A bar code printer as claimed in any one of claims 14 to 18, further comprising means which, when information on digits other than a check digit is given from the external device, automatically calculates the check digit and appends it to the last digit.

20. A bar code printer as claimed in any one of claims 14 to 19, wherein the dot pattern creating means is so constructed as to enable the bar code to be printed in either a standard WPC version or a shorter WPC version as desired.

21. A bar code printer as claimed in any one of claims 14 to 20, further comprising means for retaining, after power is turned off to the printer, the externally supplied information on the flag code and the number of dots for the minimum module and the dot patterns for the left guard bar. centre bar. right guard bar, and characters expanded to dots in accordance with the information.

22. A bar code printer constructed and arranged to operate substantially as hereinbefore described with reference 1 - 39 to and as illustrated in Figures 1 to 6 or 7 to 12 or 13 to 23 or 24 to 26 of the accompanying drawings.