An older code still popular in some industries, the Plessey code supports numbers and the characters X, B, C, D, E and F, plus a two character crc check.
Plessey
It is common practice in some industries using Plessey barcodes to separate the barcode characters from their checkdigits. This can be done by setting the EXTRA2 flag in applications or setting the flags parameter bit DL_FLAG_EXTRA2 (bit 5 of the flags variable), or by manually including a space character at the end of the barcode data.
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