Civintec CN56 Series, User Manual

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CN56X0B-X Reader User Manual
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5.5.2 Protocol
A 10-Digit BCD number transmits the 32 bit Code with a Start and Stop sentinel and Longitudinal
Redundancy Check (LRC) checksum defined as follows:
BCD 0 BCD 1 to 10 BCD 11 BCD 12
Start 32 bit code as BCD Stop LRC Checksum
B (Hexadecimal) NNNNNNNNNN F (Hexadecimal) X
Where N = 0 to 9
Each BCD Digit has an odd-parity bit appended:
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4
LSB of BCD MSB of BCD Odd Parity
1 0 0 1 1
The LRC checksum is calculated by XOR the BCD Digits including the Start and Stop Sentinel but
excluding the parity bits. The parity of the LRC checksum is also set to odd-parity, For example:
BCD Binary Parity
B 1011 0
5 0101 1
7 0111 0
0 0000 1
1 0001 0
9 1001 1
3 0011 1
5 0101 1
1 0001 0
F 1111 1
LRC 1001 1
The 24 bit Code is transmitted by a 8 Digit BCD number with a Start and Stop sentinel and
Longitudinal Redundancy Check (LRC) checksum defined as follows:
BCD 0 BCD 1 to 8 BCD 9 BCD 10
Start 24 bit code as BCD Stop LRC Checksum
B (Hexadecimal) NNNNNNNN F (Hexadecimal) X
Where N – 0 to 9
Each BCD Digit is appended with an odd-parity bit as defined above. The LRC checksum is
calculated as above.
The 13-Digit or 11-Digit BCD number is transmitted serially on the Data signal line starting with
BCD-O’s LSB.If a bit is equal to a One the Data signal line is at GND. If the bit is equal to a Zero