ZKTeco White LCD Series, Руководство пользователя

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ZKTECO White LCD Serials User Manual
Bit 2 is MSB ( most significant bit)
CC
(bit10-bit 25) Card code, (0-65,535), bit10 is MSB (most
significant bit)
Odd parity bit, OP is definite by over bit 13 to 26, if
there are odd “1”, opposition it is 0.
OP
Pyramid Wiegand Format
Several alternatives exist for customers who require more codes. The
first is to switch to Keri's standard 39 bit Pyramid format. This 39 bit
Wiegand format contains 17 bits for the facility code field and 20 bits
for the ID number field. Mathematically these 17 facility code bits allow
for a total of 131,072 (0 to 131,071) facility codes, while the 20 ID
number bits allow for a total of 1,048,576 (0 to 1,048,575) individual
ID's within each facility code. Since there are so many facility codes in
the Pyramid format, a new facility code may be selected for each project.
Additionally the large number of ID's per facility code makes the
Pyramid format ideal for very large projects. For added security, Keri
Systems tracks credential coding to ensure that no duplication occurs.
Table 3: Pyramid Wiegand Format
Bit Number Purpose
Bit 1 Even parity over bits 2 to 19
Bits 2 to 18 Facility code (0 to 131,071); Bit 2 is MSB
Bits 19 to 38 ID Number (0 to 1,048,575); Bit 19 is MSB
Bit 39 Odd parity over bits 20 to 38
Custom Wiegand Formats
The second alternative is to create a custom Wiegand format. Typically,
up to 64 bits are available for creating a custom Wiegand format. With
certain limitations, formats with greater than 64 bits may be created. If a
customer currently has a custom Wiegand format from Wiegand or from
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