User's Manual

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Appendix 2 - ISO 7811/2-1995 - Track 2 Data clock format
Compliant with ISO07811/2-1995 - Track 2.
Data encoding table
Value Bit pattern Meaning
0 0 0 0 0-1 "0"
1 1 0 0 0-0 "1"
2 0 1 0 0-0 "2"
3 1 1 0 0-1 "3"
4 0 0 1 0-0 "4"
5 1 0 1 0-1 "5"
6 0 1 1 0-1 "6"
7 1 1 1 0-0 "7"
8 0 0 0 1-0 "8"
9 1 0 0 1-1 "9"
10 (A
hex
) 0 1 0 1-1 unused character
11 (B
hex
) 1 1 0 1-0 start sentinel (start character)
12 (C
hex
) 0 0 1 1-1 unused character
13 (D
hex
) 1 0 1 1-0 eld separator
14 (E
hex
) 0 1 1 1-0 unused character
15 (F
hex
) 1 1 1 1-1 end sentinel (stop character)
The least signicant bit of every digit is sent rst; the fth bit is
an odd parity bit for each group of four data bits.
The complete message always looks as follows:
left
edge
start data
characters
end LRC right
edge
The LRC is calculated by the following procedure: each of the
4 bits in the LRC character is an even parity bit of the equivalent
bits in the telegram including start and stop sentinel.
The fth bit is the odd parity of the four LRC bits (it is not
calculated over all the parity bits).
Appendix 2