THE CMX-24I BOARD
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Data and design subject to change without notice. Supply subject to availability
© Copyright by CERBERUS AG, CH-8708 Männedorf, Switzerland 1995
01.96
E1110A.DOC
4 The CMX-24I board
The CMX-24I is the CMX board with 24 inputs and no outputs. The CMX-24I is composed of a CPU board (marked
CD91201) and an I/O board (marked CD91200), connected together (see Fig. 4.1) for board layout and assembly).
The important features to be detected on the CPU board are:
•
the reset pushbutton
•
the switch block marked SW1
•
the switch block marked SW2
Although the CPU board layout is the same for all the CMX models, the boards are configured and operate differently in
the three CMX models. The CPU board contains all the hardware and software needed for communications and
interfacing. You can easily recognize the big CPU chip, and next to it the quartz crystal (XTAL) in its metal case. If you
look at the board with the CPU chip at right, you can detect at the right of the quartz a small black pushbutton. This is
the reset pushbutton, that starts the CMX diagnostics routines and reset the field status. This pushbutton has to
pressed only when the CMX needs a full restart. When it is pressed, the status of all inputs is re-read.
I/O BOARD
CPU BOARD
FRONT
VIEW
I/O 1
I/O 23
I/O 2
I/O 24
TX
POWER ON
RX
BT
Fig. 4.1
At the right of the CPU chip, at the upper and lower side, there are two switch block, used to set:
−
the baud rate (SW2-6, SW2-7, SW2-8) : see Annex A, Table A.1;
−
the I/O status (normal/inverted) (SW2-1, SW2-2, SW2-3): see Annex A, Table A.2;
−
the board network address (SW1-4, SW1-5, SW1-6, SW1-7, SW1-8) : see Annex A, Table A.3;
−
the board type (SW1-1, SW1-2, SW1-3): see Table 4.1.
Five switches on the SW1 are used to set the board address (see Annex A, Table A.3). Five binary switches allow 2
5
=
32 addresses, but remember that only 16 CMX can actually be addressed on a single communication line. Never use
addresses above 15 (0F Hex); the
SW1-4 setting must be always ON
.
