Information on ABC fonts

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Trial Font Info

The latest version of this file can be viewed on the ABCfont.com web site by clicking here

The font you downloaded is a demonstation font. Some characters are disbled. Details on how to purchase a fully working font may be found on the ABCfont web site

Details of scanners capable of reading this 'Code 39' font may be found on the BarcodeMan web site

Code 39

This text relates to the following ABC (Altek Barcode) TrueType fonts...

Filename

If you have a font where the last letter of the filename is X (example ABC3912X) then the font is a demo, restricted use, evaluation copy only. Some barcode characters have been removed from the font and the fontname will have an x character after the ABC (example ABCx C39 Tall). These demo fonts may be removed from your system in favour of 'full copy' fonts listed above.

The fonts are suitable for use with a computer running any version of the Microsoft Windows operating system.

Contact Details

All enquiries related to this font should be directed to...

Copyright notice

The fonts to which this text refers and all associated files including this one are copyright material. All rights are reserved by the copyright owner. The fonts and other files may not be distributed, copied or installed on a computer system other than as defined in a license agreement between a licensee and Altek Instruments Ltd, UK.

How to install a font

Each barcode font is installed in the same way as a regular text font. Procedures vary slightly from system to system. You should refer to your Windows documentation or Windows Help file. If you are installing this font as a replacement or upgrade for an earlier version of the same font name or file name you should first uninstall the existing font.

Warning: DO NOT attempt to install or remove a font from your system by directly copying a file to or deleting a file from the C:/Windows/Fonts directory. DO NOT attempt to install (or remove) a font from a remote machine across a network by direct file copying or deleting. Follow the procedures given here.

In case of difficulty contact our Support Desk at ABCfont.com by phone or email (contact details can always be found on our web site).

Most Windows users may follow this route to install a font...

How to un-install a font

Transferring documents using these fonts

Documents using these fonts will display and print correctly only if the font is installed on the machine used for viewing or printing (or your Application Program supports 'font embedding- See below)'. If a document using a particular font is loaded onto a computer system where that font is not installed the Application Program will usually substitute an alternative font. This will probably be a regular text font, typically Courier or Arial. Copying the barcode font to another machine to view the document is not permitted unless that machine is covered by your existing license or an additional license is purchased. Please contact us at ABCfont if you have any questions relating to use or need help with any other license issues.

Font Embedding

Altek have taken a policy decision to permit font embedding where the application supports it. Our fonts are enabled for 'read only font embedding' which enables viewing and printing of documents containing a font even if the font is not installed on the computer. However it will not be possible to edit the document unless the font is actually installed on the computer.

Code 39 Barcode Character set

The Code 39 barcode character set consists of 43 regular characters plus an additional character used as a start and stop character.

Notice that the alphabetic characters are all upper case and that the number of symbols available is limited to a subset of those available in the full ASCII set. If you wish to use lower case letters or other ASCII characters then 'Extended Code 39' must be used (see later).

Start and Stop characters

In any 'Code 39' barcode the start/stop character must always be present as the first and last character in the barcode character string. If they are not present the barcode scanner will not be able to recognise the barcode.

The start/stop character is generally represented in the human readable text as the * character.

Code 39 Font Character Mapping

In this font the 43 regular barcode patterns are mapped to the expected ASCII/ANSI characters. The start/stop bar pattern is mapped to the * (star/asterisk) character.

The 'SPACE' character problem

The 'space' character is mapped to the _ (underscore) character. This is to avoid the problem where many Windows applications do not use the space character from the font but generate their own internal spacing. If you need to encode the 'space' character in a barcode you should use the underscore character.

Invalid Code 39 Characters

All invalid barcode characters produce a 'box' character on the screen. This is an easily recognised method to alert you to the use of an invalid barcode character.

Text Justification

If your applications program includes the ability to justify text (most word processors) it should be disabled for the barcode text. Otherwise the application may insert extra space between the bars which is likely to result in bad scanning performance.

'Extended Code 39'

The 'Extended Code 39' format enables you to encode all the 128 ASCII characters but the cost is a barcode of increased length. For this reason barcode systems employing 'Code 39' are often designed to use just the regular character set. This is clearly a compromise but one that is acceptable in most situations. However if you have a special application need that necessitates use of the whole ASCII set then 'Extended Code 39' must be used. Note that Barcode Scanners cannot differentiate automatically between regular 'Code 39' and 'Extended Code 39'. The scanner has to be programmed to decode either Regular or Extended versions. Therefore it is not possible to mix regular and extended 'Code 39' in any one application without some thought and planning.

'Extended Code 39' obtains the additional characters by combining two regular 'Code 39' characters. A suitably programmed barcode scanner interprets the character pair as a single ASCII character. The table at the end of this file lists the pairs required to encode the whole 128 ASCII character set.

For example if you wished to encode the ASCII BEL character you would use the $G pair. The barcode scanner will interpret $G as a BEL if it has been pre-programmed to read 'Extended Code 39'.

Many characters retain their original encoding- SPACE, all numerics and all Capital Alpha characters.

Lower case Alpha, control and most symbol characters MUST be encoded.

The 4 characters % $ / + NEED not be encoded UNLESS they are followed by an alphabetic character. However it is better to encode these characters to avoid potential errors in decoding where subsequent editing of the character field might produce an ambiguous combination.

If the 4 characters % $ / + can be GUARANTEED always to be 'double character encoded' then the barcode application can be optimised for both barcode length and the ability to encode all the ASCII character set providing the Barcode Scanner is set to recognise 'Extended Code 39'.

Font sizing and scaling

Most barcode fonts will produce satisfactory barcodes providing the barcode is printed large enough. Altek barcode fonts are better. Altek fonts use proprietary information to include a factor designed to compensate for the barwidth errors introduced by the physical printing process.

These techniques have been developed over a period exceeding 15 years experience in the barcode printing field. The result is a font that will print reliably at sizes smaller than most other fonts using the same paper stock and printing process. This can provide a useful increase in the density of information in the barcode.

The minimum barcode size will depend on many factors and may have to be determined ultimately by experimentation if you wish to achieve the maximum possible data density. The paper, ink, printing process and of course the barcode scanner resolution all have to be considered.

Using this font with a 300 dpi inkjet or laser printer and good quality paper you should be able to achieve consistent barcodes printed at a density of up to about 10 characters per inch (0.4 chars per mm) and this will be achieved by selecting a 12 point font size. Under good conditions it may be possible to print smaller. However few barcode scanners will be capable of reading such ultra high density barcodes. Below 12 points a 300 dpi printer will suffer from aliasing problems and sometimes smaller sizes give better results than larger. In tests we found 7 and 9 point sized barcodes were better than 8 and 10 point sizes. We found 7 point barcodes to be about the smallest to print clearly and this is beyond the resolution range of most barcode scanners.

Most applications do not need such high densities and it is good practice to print at larger sizes so any barwidth errors introduced by the printing process are minimised. A good size to aim for is about 24-26 points. Many barcode scanners of the CCD type have a maximum barcode width of about 2.3 inches (60mm) so it is a good rule of thumb to print up to this width but not beyond it. Particularly if you do not know how the barcode will be scanned. The following table shows the approximate barcode size alongside the selected point size. The suggested optimum size barcode for regular work is 24 or 26 points.

Colors

Barcode fonts need to be printed with a certain minimum contrast between the bars and spaces. This is best achieved by printing in black ink on a white background. Other color combinations may be suitable particularly if the bars are printed in dark colors towards the blue end of the spectrum and the background is a light color towards the red end of the spectrum. More information and examples of good and bad color combinations may be found on our web site.

Related Web Sites

Altek Instruments maintains a number of web sites containing much useful information about barcode identification and showing our range of barcode and auto ID related products.

Trademarks

Trademarks mentioned in this text are acknowledged

EXTENDED CODE 39 CHARACTER TABLE