Siemens Cerberus GW-21, Technical Manual, Page: 9 / 44

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Siemens Building Technologies
Cerberus Division
E1481b
06.2000
2.3 The connection board
The connection board has two connectors to insert the CPU and I/O board in.
All the UARTs, from 1 to 6, are accessible through screw connectors located on the
right side of the connection board. Only the TX, RX and GND signals are available.
UARTs 5 and 6, if the expansion board is installed, are accessible on the same con-
nector.
In the lower right corner of the connection board there is the power supply block with
two pins and -. You must connect here the voltage source (10 to 30 V d.c.).
GND
RX6
TX6
GND
RX5
TX5
GND
RX4
TX4
GND
RX3
TX3
GND
RX2
TX2
GND
RX1
TX1
+
-
Vdc
Expansion board
CPU board
Fig. 3 The connection board
2.4 The assembled gateway
The three components (the CPU board, the Expansion board, the Connection board)
can be assembled in two different ways.
The following table shows these configurations:
CPU board Expansion board Connection Board
GW-21.06 x x x
GW-21.04 x x
Tab. 2