Printronix ThermaLine Series - Manual (Page 167)

5–29 Bar Codes
Quiet Zone
Both ends of the bar code structure require blank quiet zones. The quiet
zones must be at least 0.25 inches wide and completely blank to ensure
accurate reading of the start/stop codes and to prevent adjacent bar codes
from overlapping. Be sure to provide sufficient space on the form for the
quiet zones.
Start/Stop Codes
The start/stop codes identify the leading and trailing end of the bar code.
Code 93 Data Field
The bar code symbol uses a series of varying width bars and spaces to
represent an extensive character set. The bars and spaces vary in width
from one to four modules. Each character consists of three bars and three
spaces that total 11 modules.
Readable Data
The optional readable data field provides a readable interpretation of the
bar code data. It can be printed above or below the bar code symbol.
Check Digit
The modulo–103 check digit is automatically calculated and inserted in the
bar code symbol. The check digit verifies accurate scanning. The start code
is included in the check digit algorithm.