symbology. However mod 10/3 checksum is most common. Example for the first 6 digits 123456: 10 - ((3*1 + 2 + 3*3 + 4 + 3*5 + 6) mod 10) = 1. Check digit is 1. Result: 1234561 barcode Datalogic 2 of 5 Data Logic 2 of 5 (also known as Code 2 of 5 Datalogic, China Post Code) is proprietary Chinese version of Matrix 2 of 5 symbology developed by Datalogic. It has difference from Matrix 2 of 5 code only in start/stop patterns usage and, in this way, it has all advantages and issues of Matrix 2 of 5. Datalogic 2 of 5 was used mostly in Chinese Postal Services. Some readers currently still support this symbology N - narrow black bar or white space. W - wide black bar or white space. See also Automated identification and data capture (AIDC) Barcode Code 2 of 5 Datalogic Interleaved 2 of 5 References External links Datalogic 2 of 5 description Matrix 2 of 5 and Datalogic 2 of 5 generator Matrix 2 of 5 structure Automatic identification and data capture Barcodes Encodings