
17
Appendix B. Wiegand Specification
Data Pulses
The Data One and Data Zero signals are normally held at a logic high level until the data is ready to be sent. Data is sent as below on
Data1 or Data0 lines. The following timing parameters shall be observed:
D ata One
D ata Z ero
Tpw
Tpw
Tpw
Tpi
Tpi
Voh
Voh
Vol
Vol
Tpw Pulse Width Time -- 20
µ
Sec (minimum) to 100
µ
Sec (maximum)
Tpi
Pulse Interval Time -- 200
µ
Sec (minimum) to 20
m
Sec (maximum)
Wiegand interface
(26-bit format):
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
P S S S S S S S S C C C C C C C C C C C C C C C C P
P E E E E E E E E E E E E
O O O O O O O O O O O O P
Summed for even parity (E)
Summed for odd parity (O)
Wiegand interface
(30-bit format):
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
P S S S S S S S S C C C C C C C C C C C C C C C C C C C C P
P E E E E E E E E E E E E E E
O O O O O O O O O O O O O O P
Summed for even parity (E)
Summed for odd parity (O)
Wiegand interface
(34-bit format):
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
P S S S S S S S S S S S S S S S S C C C C C C C C C C C C C C C C P
P E E E E E E E E E E E E E E E E
O O O O O O O O O O O O O O O O P
Summed for even parity (E)
Summed for odd parity (O)