For reading bar codes into an Access application, you have two
choices.
Most bar code readers are available with one of two output options.
The first option is called "Keyboard Wedge" output where you unplug
your keyboard, plug the bar code reader into the keyboard port on your
PC and then plug your keyboard into the bar code reader. This
arrangement makes the bar code reader appear as it it were simply a
second keyboard. Your original keyboard continues to work as normal
however when you read a bar code, the data encoded in the bar code
appears to any application running on your PC as if it were typed in.
The keyboard wedge interface is extremely simple however it has a few
drawbacks. If you scan a bar code, the cursor has to be in the correct
input field in the correct application otherwise you end up reading
bar code data into whatever application has the focus. This can cause
all sorts of potential problems if the cursor is not in the right
place when the bar code is scanned. The keyboard output also is
limited in that you cannot modify the data in any way before sending
it into the program that is to receive the data. For example, if you
needed to parse a bar code message up into pieces or remove some of a
bar code message or add in a date or time stamp you would not be able
to with a normal keyboard wedge reader.
The other possible output option is to get a bar code reader with an
RS232 or "Serial" interface. With these types of bar code readers, you
connect the reader to an available serial port on the back of your PC.
You would then need a program called a "Software Wedge" to take the
data from the bar code reader and feed it to the application where you
want the data to go. The disadvantage to this approach is that it is a
little more complex however you gain much more control over how and
where your data ends up when you read a bar code. With a Software
Wedge, you can control exactly where the data goes in the target
application and you can also perform all sorts of modifications on the
data before it is sent to the application.
TAL Tehchnologies sells a product called WinWedge which is a Software
Wedge for Windows.
Visit:
http://www.taltech.com/products/winwedge.html
for more information about WinWedge.
TAL also sells a very high quality line of bar code laser scanners at
very reasonable prices. All their scanners are available with either
the keyboard wedge output or RS232 output. For scanners see:
http://www.taltech.com/products/bc_reader.html
This web site is also an extremely good place to obtain information
about bar coding in general be sure to look in the Resources section
of the site for a bar code tutorial.
For printing bar codes from Access, you would be best off using a bar
code ActiveX control like the one fromTAL Technologies at the
following URL:
http://www.taltech.com/products/activex_barcodes.html
If you need to print bar codes, I would recommend that you download
the demo of the TAL Bar Code ActiveX control from the above URL and
take a look at the sample Access database that is provide with the
demo.
You can also use bar code fonts to do the job and many are available
for free on the web however you will definitely want to test your bar
codes by printing them to the particular printer that you will be
using and then scanning them with the bar code scanner that you
purchase. Fonts are notorius for producing very poor quality bar codes
that are difficult to read. They also offer very little flexibility in
size. Three things that you should always do when using bar code fonts
are to test, test, and test again.
