25
If you choose the
WIEGAND
protocol 1,2,3,6,7 and 9 (pages 20…22) it is possible that the
Mor-
pheus
transceiver code exceeds the maximum code length that can be represented by the avail-
able bits. With jumper "
J1
" not inserted, no
WIEGAND
output will occur, code information on the
RS232
line will however be available.
Inserting jumper "
J1
" activates the "
code truncation
" function which eliminates the most signifi-
cant bits which cannot be represented by the chosen
WIEGAND
format.
E.g. 1
:
If you choose the 26 bit
WIEGAND
protocol with site code (limit
65’535
) and the transmitter code is
356’890
, the truncation function will cancel the first bit and the code effectively sent in
WIEGAND
output will now be
56’980
(A number less than
65’535
).
E.g. 2
:
If you choose the 37 bit BCD
WIEGAND
protocol with site code (limit
542’287
) and the transmitter
code is
18’436’500
, the truncation function will return the code
436’500
.
Attention!
Activating the "truncation function" (jumper "
J1
" inserted) it is possible that two
transmitters (even though they have different codes) send an identical sequence of bits to
the interface output.
For example in the case of the
WIEGAND
26 bit protocol with site code the codes
138’612
and
238’612
will activate the same bit sequence in output,
38’612
.
CODE TRUNCATION
Содержание MORPH433W01
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