[log in to unmask] (CValdes) wrote:
 
>I have the need to print barcodes(CODE128)  to Laserjet III's and 4's
from
>a legacy Cobol program running in my 3k.
 
>I would like to somehow download a file with the font to the printer, and
>then select to print specific lines with the barcodes.
 
>Does anyone know of a "free" or cheap font barcode fileand how I can get
a
>hold of it?
 
I have created a downloadable Code 128 PCL-5 soft font for HP laser
printers.  It's not free, but I think it would fall under the cheap
category.  Send me an e-mail message if you would like more info.
 
The way you download a font is to simply copy the font file to the printer
(binary copy).  The file contains the necessary control codes so the
printer will store it in memory.  I usually tag the font with a
'permanent' flag so that it won't be erased by printer resets.  The only
way to remove the font is to copy in a new one or power down the printer.
The font is selected with a PCL-5 font selection command; the ID number of
the font is embedded in the font file.
 
Code 128 has a lot of capability and, therefore, a few complexities.
There are 103 characters in the set plus start codes for 3 subsets (A, B,
and C) and a stop character.  By selecting 1 of the 3 subsets, you can
encode any ASCII character (printable or control).  Subset A contains
standard ASCII characters  and control codes, but no lower case.  Subset B
contains ASCII characters, upper and lower case.  Subset C compresses
numeric-only data by squeezing two digits into each barcode character.
 
After you have built the barcode with the required start characters and
data (you can change subsets within a barcode), you have to append a
Modulo 103 checksum.
 
Code 128 has two distinct benefits:  1) Complete range of characters and
control codes, and 2) very dense printing of numeric-only data.  If you
don't need either of those features, you might want to consider Code 39.
It has a more limited range of characters, but it is a 'self-checking'
code and needs no checksum.  You can download a Code 39 font to the print,
change fonts, and print your data enclosed within asterisks.  That's it.
 
Good luck; drop me a note if you need more info.
 
 
Bob Lounsbury
MEC Software
bar code specialists