You can enable symbology identifiers in most scanners. For example, if you enable the GS1 Code 128 identifier and scan a Code 128 symbol that encodes F1 0123456, where F1 is a 128 function 1 code, the scanner will output “]C10123456”. The left square bracket precedes the symbology type, the letter indicates the symbology, and the number after the letter is the specific parameter for that code.
These identifiers are used by programs to ensure that he correct symbology and type is being used. A quick listing of the important codes and modifiers:
A Code 39
0 = No check digit
1 = Check digit, transmitted
3 = Check digit, not transmitted
4 = Full ASCII, no check digit
5 = Full ASCII, check digit transmitted
7 = Full ASCII, check digit not transmitted
C Code 128
0 = Standard Code 128
1 = GS1 Code, Function 1 in the first position
2 = Function 1 in second position
4 = Concatenated according to ISBT rules
d Datamatrix
0 = ECC 0 – 140
2 = ECC 200, Function 1 in position 1 or 5
3 = ECC 200, Function 1 is position 2 or 6
4 = ECC 200, Extended Channel Interpretations implemented
5 = ECC 200, Function 1 in position 1 or 5, ECI implemented
6 = ECC 200, Function 1 in position 2 or 6, ECI implemented
E UPC
0 = Standard code, except for EAN-8
1 = Two digit supplemental code
2 = Five digit supplemental code
3 = Combined UPC and supplemental code
4 = EAN-8