NCR 7870 manual Bar Code Type, Common Byte, Unique Identifier

7-36 Chapter 7: Programming

Note: Refer to the ASCII Code Chart for the Hex Characters; however, values of 20 to 7E are recommended. Do not use the same characters as the Terminator Byte or the message may terminate too soon. Also, a Common Byte cannot be 00.

If you are not going to use a Common Byte, you can scan any Hex tag twice except Hex 0 or the Terminator Byte value. The default for Common Byte 1 is 5D (ASCII ]) and the default for Common Byte 2 is 42 (ASCII B). You must scan four tags to go to the next parameter.

Bar Code Type

The Bar Code Type parameter selects the bar code type for entering its associated label identifier information. After entering a Bar Code Type, enter the Common Byte, Unique Identifier, and Version Number if applicable. This procedure repeats until the label identifiers are specified for each bar code type. Scan the Hex 0 through Hex 7 tag to enter the appropriate Bar Code Type. Since you must select each of these individually for your application, there is no default for this parameter.

Common Byte

The Common Byte parameter selects which common bytes, if any, to add to the bar code data message. Each entry is unique to the previously specified Bar Code Type. Scan the Hex 0 tag for no Common Bytes, the Hex 1 tag for Common Byte 1, the Hex 2 tag for Common Byte 2, or the Hex 3 tag for both Common Bytes. The default for this parameter uses Common Byte 2 as a suffix for Code 39, Code 128, and Interleaved 2 of 5 bar code data. UPC and EAN bar codes do not use Common Bytes.

Unique Identifier

The Unique Identifier parameter permits you to specify the data sent to the host terminal in the Unique Identifier field. Each entry is unique to the previously specified Bar Code Type. Enter this data as two Hex characters using recommended values of 20 to 7E (Refer to the ASCII Code Chart). The following are the default values.