HIKVISION DS-2CD7A26G0/P-IZHSWG, Руководство по эксплуатации, Страница: 7 / 20

Wiegand Camera
·
Operation Manual
5
The front
parity bit
(even parity
bit)
8-bit
（
To express the site
code ID, if the site
code ID is less than
8 digits, 0 will be
added before the ID
until it is 8-digit
number.
）
16-bit
（
To express the card
ID, if the card ID is
less than 8 digits, 0
will be added before
the ID until it is
16-digit number.
）
The rear
parity bit
(odd parity
bit)
Coding Process:
1. Card number is made up of card ID and site code.
2. Convert card ID A to binary format, as C.
3. Covert site code B to binary format, as D.
4. The combination of site data and card data is D + C.
5. The front parity bit is the even parity bit of the first half of D + C.
6. The rear parity bit is the odd parity bit of the second half of D +C.
7. The return result: front parity bit + D + C + rear parity bit.
Note the order of the combination of site data and card data is D + C.
Example:
Card number: 12345 011
The coding process are show as below.

Split the card number as the card ID (12345) and site code (011).

Convert 12345 to binary format, as: 0011000000111001.

Convert 011 to binary format, as: 00001011.

Site data and card data as: 00001011 0011000000111001

Bit 1 is an even parity bit for the following 12 bits (bit 2 to bit 13), as 1.

Bit 26 is an odd parity bit for the previous 12 bits (bit 14 to bit 25), as 1.

According to the converting mode(Even parity bit + site data + card data +
odd parity bit), you can get a binary code as: 1 00001011
0011000000111001 1.