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Chapter 3 Bar Codes
Modulo-103 Check Digit
A modulo-103 check digit is automatically calculated and inser ted in the bar
code symbol immediately in front of the stop code, in the same manner as the
C128 bar code. The check digit verifies accurate scanning. The start code is
included in the check digit algorithm. The modulo-103 check digit is not
displayed in the readable data field.
Modulo-10 Data Field Check Digit for SSCC-18 and SCC-14
AI 00 (called the Serial Shipping Container Code, or SSCC-18) takes
eighteen additional numerical data bytes. The last data byte is a modulo-10
check digit on the preceding seventeen data bytes. Counting the two zeros of
the application identifier, the modulo-10 check digit is the twentieth byte in the
data field.
AI 01 (called the Shipping Container Code, or SCC-14) takes fourteen
additional numerical data bytes. The last data byte is a modulo-10 ch eck digit
on the preceding thirteen data bytes. Counting the zero and the one of the
application identifier, the modulo-10 check digit is the sixteent h byte in the
data field.
The modulo-10 data field check digit for both SSCC-18 and SCC-14 is printed
in the bar code as the second half of the last number pair using subset C. It is
displayed in the human-readable data field as the twentieth byte for SSCC-18
or the sixteenth byte for SCC-14.
IGP/PGL automatically calculates the modulo-10 check digit for SSCC-18 if
only 17 data digits are provided following the application identifier of 00.