ZKTeco White LCD Series, Руководство пользователя

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ZKTECO White LCD Serials User Manual
About Wiegand
The device pursuant the Wiegand standard specified by the Security
Industry Association's (SIA) Access Control Standard Protocol for the
26-Bit Wiegand Reader Interface document. Manufacturers have
adopted the Wiegand standard to establish a common Wiegand interface.
This provides a level of compatibility and interoperability for readers
and control panels that can be used by consultants, specifies, and end
users when setting product design or system installation criteria.
Data Signals
The figure below displays the timing pattern for data bits sent by the
reader to the access control panel. This timing pattern falls within the
Wiegand guidelines as proscribed by the SIA's Access Control Standard
Protocol for the 26-Bit Wiegand Reader Interface (a Pulse Width time
between 20
μ s and 100 μ s, and a Pulse Interval time between 200 μ s and
20ms). The Data 1 and Data 0 signals are held at logic high level (above
the Voh level) until the reader is ready to send a data stream. The reader
places data as asynchronous low-going pulses (below the Vol level) on
the Data 1 or Data 0 lines to transmit the data stream to the access
control panel. The Data 1 and Data 0 pulses will not overlap or occur
simultaneously. Table 1 provides the minimum and maximum allowable
pulse width times (the duration of a pulse) and pulse interval times (the
time between pulses),
Table 1: Pulse
Symbol Description Reader typical Time
Tpw Pulse Width Time 100 μ m
Tpi Pulse interval time 1ms
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