A Code 93i symbol can be structured one of two ways, with two check digits or with error correction.

Symbol Structure with Check Digits

The symbol comprises the following elements:

• Leading quiet zone

• Start character

• One or more characters that represent the data and special characters

• Two check digits

• Stop character

• Trailing quiet zone

Symbol Structure with Error Correction

The symbol comprises the following elements:

• Leading quiet zone

• Start character

• Three error correction characters

• One or more characters that represent the first part of the data and special characters

• A special features flag character that is followed by a symbol length indicator character

• Zero, one, or more characters that represent the rest of the data and special characters

• Three error correction characters

• Code 93 stop character

• Trailing quiet zone

Each character in a Code 93i symbol is made up of three bars and three spaces, each of which can be one to four modules wide. These six elements are spread out over a space that is nine modules wide.

Different combinations of Code 93 and Code 93i start and stop characters yield different versions of the symbologies:

• Code 93 start and Code 93 stop: Code 93

• Code 93 start and Code 93i stop: Code 93i-Regular

• Code 93i start and Code 93 stop: Code 93i-EC (error correction)

• Code 93i start and Code 93i stop: Code 93i-Composite

This symbology supports the following characters:

• All numeric digits (0-9)

• All uppercase letters (A-Z)

• The following symbols:

  • Percent sign (%)

  • Plus sign (+)

  • Dollar sign ($)

  • Slash mark (/)

  • Period (.)

  • Hyphen (-)

• Space character

• Shift and special function characters

The shift and special function characters are used as needed to encode other characters from the 128-character ASCII set.

Additionally, Code 93i uses mode characters, which indicate that groups of characters have been combined in a certain way to save space or to represent certain types of data. They can also be used to indicate a switch between modes or between a mode and the base character set. The mode characters are Numeric (used to compress numeric strings), Word (used to encode Unicode data), and Byte (used to compress byte data strings).

Code 93i contains either two mandatory check digits that immediately follow the data message or a special features flag character that is inserted in the center of the code to signal error correction.

The check digits version of Code 93i uses the modulo 53 (mod 53) algorithm. The error correction version of Code 93i uses the Reed-Solomon algorithm.

The recommended minimum symbol height for manual scanning is 5.0 mm or 15 percent of the symbol width (excluding quiet zones), whichever is greater. The quiet zones must be at least 10 modules wide.