User's Manual

I-1
Appendix I
Interleaved 2 of 5 Code
Specifications
Interleaved 2 of 5 Code is a numeric-only, even-number-of-digits bar code.
It is widely used in warehouse and industrial applications. A combination
of five elements, two wide and three narrow represent each character. Odd-
number position digits are encoded in the bars, even-number positions in
the spaces.
Interleaved 2 of 5 Code is so susceptible to partial scans
being interpreted as valid reads that we recommend at least
one of the following safeguards:
• Use one length of I 2 of 5 code. Using one length of data allows
you to tell the RF Terminal to look for one length of I 2 of 5
code only. By default, the RF Terminal is set to look for a 6
digit I 2 of 5 code but you can set the length to something
different using the RF Terminal Setup Menu. Setting the length
to 00 digits allows variable length bar codes scanning. If you
must use the 00 setting, we recommend that you then use the
“Minimum/Maximum” data length field when creating a program
in the RF Terminal to check each field for the proper length.
• Use a check digit. Worth Data's LabelRIGHT printing program
automatically calculates and prints a check digit upon request
using the method below:
Interleaved 2 of 5 Mod 10 check digit calculation
1. Assume that the bar code data is 1987.
2. Starting with the least significant digit (in this case, a 7), label
the digits alternatively even and odd.
7 - even
8 - odd
9 - even
1 – odd
3. Take the sum of the odd digits:
8 + 1 = 9
123456