Telepen

with each bar code. The start/stop code structure permits bar code scanning in a left-to-right direction only.

Data Field

The bar code data produces a single field of 30 bars for a 5-digit field, 50 bars for a 9-digit data field, or 60 bars for an 11-digit data field. The bars are grouped in sets of five. Each set of five bars (comprised of two tall bars and three short bars) represents one of the five digits of the zip code, plus the four-digit zip code extension. If the Advanced Bar Code is used, an additional two-digit code is also added to make an 11-digit data field.

Check Digit

The sixth, tenth or twelfth digit represents the automatic check digit character for the 5, 9 or 11-digit data field, respectively. The check digit is added automatically to verify accurate scanning.

Telepen

The Telepen structure is shown in Figure 20 and described below.

 

 

 

OPTIONAL

 

 

 

 

CHECK DIGIT

 

SR, SC

 

 

 

 

POSITION

 

 

 

 

 

 

UPPER GUARD BAND

 

QUIET

START

DATA FIELD

STOP

QUIET

ZONE

CODE

 

CODE

ZONE

HEIGHT

LOWER GUARD BAND

OPTIONAL READABLE DATA FIELD

Figure 20. Telepen Structure

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 code is a unique character identifying the leading and trailing end of the bar code. The start/stop code is automatically produced with each bar code. The start/stop code structure permits bidirectional bar code scanning.

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IBM 4400 manual Telepen