Bar Code Scanner Details...                Version 1.1.22

(Version 1.1.22 corrects one error in coupon value codes from version 1.1.21)

The scanner firmware decodes many of the common 1D (1-dimensional) bar code
symbologies. It has been tested with the following symbologies...

     UPC A
     UPC A + 2 digit supplemental
     UPC A + 5 digit supplemental
     UPC E  (Shown both compressed and expanded)
     EAN 13  (European Article Numbering)
     EAN 13 + 2 digit supplemental
     EAN 13 + 5 digit supplemental
     EAN 8
     JAN 13  (Japanese Article Numbering)
     JAN 13 + 2 digit supplemental
     JAN 13 + 5 digit supplemental
     ISBN  (International Standard Book Number)
     ISBN + 2 digit supplemental
     ISBN + 5 digit supplemental
     ISSN  (International Standard Serial Number for periodicals)
     ISSN + 2 digit supplemental
     ISSN + 5 digit supplemental
     ISMN  (International Standard Music Number)
     ISMN + 2 digit supplemental
     ISMN + 5 digit supplemental
     Code 39
     Code 128
     Interleaved 2-of-5
     Codabar

     cue:Cat scanner proprietary (CC!)
     cue:Cat scanner proprietary (CC^)

The scanner provides a 3-character code for the bar code type. I provide a
spelled-out description of the symbologies listed above, and just the 3-
character code for any others. If you see another 3-character code, let me
know and I'll try to determine what symbology it is and add it to the program. 

The cue:Cat scanner's own proprietary bar codes, seen in some magazine ads
and some electronics stores' catalogs (in 2000) had 3-letter codes which
began with 'CC'. So far, I've seen 'CC!' and 'CC^' ... there may be others.

For symbologies where the data is typically printed in groups of digits under
the bar code (UPC, EAN, etc.) the display of the data has spaces inserted to
group the decoded digits in a similar fashion for readability.

UPC A bar codes on coupons contain a code defining the value of the coupon.
This is displayed by the program using data from the Uniform Code Council
which is current as of July 2001.

The first two or three digits of an EAN-13 barcode identify the country
in which the manufacturer's identification code was assigned (not necessarily
the country in which the goods were manufactured). This information is
displayed from data which is current as of 2002.

UPC E is a special case, smaller footprint version of the UPC bar code where
for certain kinds of data containing many zeros, the zeros may be removed,
with the last digit determining the method of restoring the missing zeros to
produce the equivalent full-sized UPC A value. (All UPC E bar codes represent
a 'zero-suppressed' version of a legitemate UPC A code.) The display of a
scanned UPC E bar code will be shown compressed and expanded.

The scanned data is also placed in the Windows Clipboard (without added
spaces) so that it may be pasted into other Windows applications. 

The scanner is a 'keyboard wedge' device - the encrypted scan data enters the
PC as though it had been typed in on the keyboard. This program receives that
input in the text-entry area at the bottom of the window and decrypts and
processes the data when the last character from the scanner, a Carriage-Return
character, 'pushes' the [Input:] button in the lower-left corner of the
window, which is the window's 'default' button (thicker black border than the
other button). The program works when the text-entry area has the 'focus' and
the [Input:] button is the default botton. (The program starts this way.) You
can 'Tab' to the [Quit] button, and both the focus and the default will shift
to that button allowing you to exit without using the mouse. Tab again, and
the focus returns to the text-entry area while the default returns to the
[Input:] button - and you are ready to scan again.

This program must be the currently-selected Windows foreground program when
scanning. If you click on another program's window then it will become the
foreground program and it will receive all keyboard input. Therefore, if you
are scanning and pasting data into, say, a word processor, then be sure to
click on this program's window (or Alt-Tab to switch programs) to get back to
this program, or the next scan's raw encrypted data will be 'keyed into' the
other program.


The 'Always on Top' selection of the Options menu will cause the scanner
window to remain visible in front of other windows when checked.

The 'Append to Clipboard Data...' selection of the Options menu controls
adding a tab character, a Carriage-Return/Line-Feed sequence, or nothing (the
default) to the end of the data in the clipboard to aid in using the pasted
data in a data entry setting. 


Scanner defficiencies...

ISBN and ISSN are actually EAN 13 bar codes beginning with 977 (ISSN) and 978
or 979 (ISBN). The scanner correctly recognizes ISSN and the 978-style ISBN
but identifies the 979-style ISBN an ordinary EAN 13. I check the first three
digits of EAN 13 bar codes and correctly identify the 979-style ISBN codes.


JAN is actually EAN beginning with 45 or 49 (the EAN country codes for Japan).
The scanner correctly recognizes 49 as JAN but identifies 45 as an ordinary
EAN 13. I check the first two digits of EAN 13 bar codes and correctly identify
the 45-style JAN codes.

The scanner does not decode the check digit in a UPC E bar code. A UPC E bar
code has a start code, six data characters, and a stop code. The check digit
is encoded in the choice of odd-parity and even-parity characters used for the
six data characters. I provide what the checksum SHOULD be, and a message to the
effect that the check sum character is not decoded by the scanner when a UPC E
is scanned. (The 'Number System' character for UPC E is always zero, and is not
encoded, but rather is assumed to be present. The scanner does correctly invent
the zero and place it at the beginning of the decoded data.)

The scanner does not decode which of the five possible start and stop
characters (A, B, C, D, or E) was used in a Codabar bar code. Codabar is a
numeric bar code symbology, and the choice of start and stop characters can be
used to encode additional information. I provide a message to the effect that
the start and stop codes used were not decoded.


Other information...

This program enables the use of the cue:Cat scanner as a general-purpose
bar code scanner and symbology-identifying tool.

This program provides no functionality related in any way to the scanning of
the proprietary (type 'CCx') bar codes in connection with Web browsing
technology for purposes of going to the scanned advertizer's web site or
collecting demographic information about the visitor to such a web site - a
technology for which Digital:Convergence® Corporation holds a patent.
Therefore, this software also cannot be used to defeat the collecting of such
demographic information, as it contains no means to implement the visiting of
the scanned advertizer's sites, and it makes no attempt to hide or scramble
the unit serial number which is returned from the unit on every scan.


This program, the source code, and the VisualBasic® 6.0 Project files are
placed in the Public Domain.

The original source for the Visual Basic project I started with is in
'meow.zip' available on several Internet sites. It has the basic symbol
decoding. Thanks to that (anonymous) author for coding the decryption, and for
showing me the technique of making a 'default button' to catch the enter-key
at the end of the scanner string. I used my own several years' experience
working with bar codes to flesh out the program to clarify the symbology
types, format some types for readability, and to identify the three scanner
defects described above.

Having looked at most of the available Windows programs for this scanner, I
believe this to be the most full-featured program with regard to using this
device as a general-purpose bar code scanner.

The latest version may be found at my web site...

    http://ChuckSomerville.com/

...and you can E-mail questions or comments to...

    chucksomer@gmail.com