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Appendix A
Appendix A
Appendix A
Appendix A –
–
–
– Error Handling
Error Handling
Error Handling
Error Handling
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3M Toll RFID Reader 6204
3M Toll RFID Reader 6204
3M Toll RFID Reader 6204
3M Toll RFID Reader 6204
User’s Guide
User’s Guide
User’s Guide
User’s Guide
A
Using the Wiegand Interface
A.1.
Overview
Overview
Overview
Overview
The 3M Wiegand Interface Module (WIM)
is a serial (RS-232) to 4-channel
Wiegand module designed to interface
with the 6204 reader. Currently, 2
Wiegand channels are used,
corresponding to the 2 antennas
available on the 6204. Channel 1 is
associated with the internal antenna.
Channel 2 is associated with the
External antenna.
Channels 3 and 4 can be configured to
act as open-collector, digital pulse outputs under software control. This
requires an additional custom script file to define the output function.
Contact your local 3M Representative for further information.
A.2.
Wiegand Protocol
Wiegand Protocol
Wiegand Protocol
Wiegand Protocol
The Wiegand communication protocol is a 3-wire communications scheme
comprising:
Data One line
Data Zero line
Ground line
These three lines constitute a Wiegand Channel.
Data is transmitted in a serial manner over these lines by pulsing the Data
One line low for a logic
1
, and pulsing the Data Zero line low for a logic
0
.
Two parameters define the behavior of bit-wise transmission:
Pulse Width Time (Tpw) is the duration of the pulse.
Pulse Interval Time (Tpi) is the interval between the end of a pulse and
the start of the next pulse.
Based on this, the total bit time is Tpw + Tpi.
Summary of Contents for 6204
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