Data interfaces
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Siemens Building Technologies
Fire Safety & Security Products 07.2008
13 Data interfaces
The Reader Interface offers a choice of Wiegand or Magnetic Stripe data output to
communicate with a host system. You select the interface you require by pro-
gramming a 63-bit configuration card and presenting it to the Reader, see chapter
12 Reconfiguring the function.
13.1 Electrical characteristics of outputs from the Reader
The Wiegand and Magnetic Stripe interfaces use the data lines D0, D1 and DA.
The D1 and DA outputs are driven by open drain drivers which can each sink up to
250mA. When a driver is off, its output is pulled up to +5V (the regulated logic volt-
age on the board) by a 10k resistor (and also by whatever is connected at the host
end). D0 is not pulled up - it can be driven high or low by the Reader, and can also
float in a high impedance state as shown in the diagram below.
The diagram below shows the logical implementation of the data outputs:
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