Cameron NUFLO 1141C, User Manual

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Appendix D: Input/Output Expansion Board
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Figure D.2 illustrates the position and orientation of this I/O termination connector as well as the serial
port, pulse input, and analog output configuration switches.
1 2
Serial Interface Select
RS232C
RS422
RS485
1 2 3 4 5 6
Pulse Input
Mode Select
422/485
Termination
Iout Vout
Analog Out
Select
OFF
ON
Figure D.2—I/O termination connector
Configuration Switches
As illustrated above, the board provides configuration switches for serial port, the pulse input and the
analog output. A brief description of each of the switches is given below:
Status Input/Output and Pulse Output Circuits
All settings are software-selected. Hence, there are no switches to set.
Serial Port Switches
The serial port’s configuration is controlled by both a 2-bit DIP switch and a multi-pole slide switch
(see dotted area of Figure D.2). The slide switch selects between an RS-232C interface (left-hand
position) and an RS-422/RS-485 interface (right-hand position).
DIP switch #1 selects between RS-422 ( open - OFF ) and RS-485 ( closed - ON ) interfaces when the
slide switch is in the RS-422/RS-485 position). DIP switch #2 connects a 100
Ω
termination and
should be closed ( ON ) for an RS-422 interface or if the MIO2 board is the last device on a multi-drop
RS-485 network.
Pulse Input Switches
The six-position DIP switch is used to configure the pulse input circuitry to interface with a variety of
pulse-producing devices. The function of the switches is the same as that of the switches on the