Bar Coding Keystrokes
- TAL Bar Code ActiveX Control
- TAL Bar Code ActiveX PLUS
- TAL Bar Code ActiveX Demo
- TAL Bar Code DLLs
- TAL Bar Code DLL Demo
- B-Coder Pro
- B-Coder Lite
Bar Codes can only contain ASCII Characters. Certain Keystrokes
have corresponding ASCII Characters, such as Tab (ASCII 9), ESC
(ASCII 27) and Enter (ASCII 13), while others do not - for example
Function Keys F1-F12. Furthermore, certain bar code symbologies
have restrictions on the kind of data that can be encoded - UPC
codes can only contain numerical data, so encoding a tab character
after the numbers would not be possible.
For those keystrokes that cannot be encoded, or for symbologies
that do no support those which do have ASCII equivalents, you must
add the extra keystrokes another way.
Most Bar Code scanners have options to add a prefix and/or suffix
of keystrokes or ASCII characters. For Example, using the Metrologic
Eclipse Scanner you can add up to 10 configurable prefix characters
and 10 configurable suffix characters by scanning special bar codes
in the manual to identify the prefix or suffix based on the ASCII
value. Other codes Enable and Disable commonly used characters
like carriage returns.
BC-Wedge allows you to
add a single keystroke as a suffix to the data transmitted by an
RS-232 Scanner (Enter, Tab, Left, Right, Up or Down. WinWedge allows
you to add a ANY keystroke(s) or ASCII character(s) before your
data, after your data or even in the middle of your data. WinWedge
also supports DDE (Dynamic Data Exchange) which allows you to write
code in applications such as Excel or Access that will give you
full control over where the data goes and how it is parsed and
filtered.
For keystrokes that do have an ASCII Character and can therefore
be encoded into a bar code it is possible to create a bar code
for each keystroke. Simply select a bar code symbology like Code
39 Full ASCII or Code 128 and select the character from the ASCII
Chart that represents your keystroke. You can print out a number
of Bar codes that perhaps have a comment above them telling you
what they are: Enter, Esc, Tab, Space, etc. Then you simply scan
the bar codes in order e.g. Tab, UPC Code, Enter.
Special considerations when using this technique
- You must select a bar code symbology that supports the ASCII
Characters you are trying to encode.
- You must make sure the symbology you selected is enabled on
your scanner. If you select Code 39 Full ASCII but do not enable
it on your scanner, the scanner will decode the bar code using
regular code 39, in which case your Tab Keystroke may become
something like "$I".
- Make sure that the "Minimum Symbol Length" (if you
scanner has such a setting) is set to 1 character. The Metrologic
Eclipse Scanner has a default minimum symbol length of 3
characters. Thus it will not read a single character bar code
unless you reconfigure using the manual. To Reconfigure the Eclipse
scanner follow these steps:
- Scan the Enter/Exit Configuration Mode symbol on P.2 of the
manual.
- Scan the ~Minimum Symbol Length symbol on P.13.
- Scan the Code byte 0 on P.84.
- Scan the Code byte 0 on P.84.
- Scan the Code byte 1on P.84. (this sets the minimum length
to 001).
- Scan the Enter/Exit Configuration Mode symbol on P.2 of the
manual.
|