Zebra CPCL Programming Manual - Step 2:

P5-10

Mobile Printer CPCLProgramming Manual

acter in the code which ensures that data remains intact.

Code 128 can use the entire ASCII 128 character set

as well as other subsets available in the universal sym-

bology specification.  The three start and stop characters

determine which character set to use.  The checksum for

this bar code is located immediately before the stop

character.  The bar code symbology specification con-

tains all the information on calculating this checksum.

For a short example, we desire to encode “BAR128” in a

bar code.  We will use “A” as our start and stop character

in this example.

Step 1: The symbology specification assigns a numeri-

cal value for each character.  Find the values of all the

characters in the data.

Step 2:

Add the value of the start character and all the

data characters multiplied by its position in the bar

code.  For our example, the calculation would be 103

+ (34 x 1) + (32 x 2) + (50x 3) + (17x 4) + (18x 5) +

(24 x 6) = 672.

Step 3:

Divide this number by 103.  The remainder or

modulo, 54, is the checksum.  The character that

assigned to 54 in the specification is “V”.  Our final

code will look like “ABAR128V” where “A” is the start

character, “BAR128” is the data, and “V” is the

checksum.

The UCC-128 Shipping Standard is part of a document

called 

Application Standard for Shipping Container Codes

available from the Uniform Code Council.  This 90-page

guide contains the entire specification on marking any

shipment sent anywhere in the United States. Seventeen

pages are dedicated to the technical considerations of

using, placing, and printing these bar codes.  We highly

recommend getting this information if your application

involves shipping.