User manual

905U-G Wireless Gateway User Manual
Page 33 ©September 2004
All eight of the 105G DIO terminals may also be used as discrete outputs. The digital
outputs are transistor switched DC signals, FET output to common rated at 30VDC 500 mA.
Digital outputs may be configured to individually turn off if no command message is
received to that output for a certain period. This feature provides an intelligent watch dog for
each output, so that a communications failure at a transmitting site causes the output to revert
to a known state. See Chapter 4 Configuration for further details.
The output circuit is connected to the appropriate “DIO” terminal. Each digital output circuit
includes a LED indicator which is lit when the digital output is active.
3.5 Serial Port
3.5.1 RS232 Serial Port
The serial port is a 9 pin DB9 female and provides for connection to a terminal or to a PC for
configuration, field testing and for factory testing. It is also used by the Modbus/DF1 version
for fieldbus connection.
This port is internally shared with the RS485 - ensure that the RS485 is disconnected before
attempting to use the RS232 port. Communication is via standard RS232 signals. The 905G
is configured as DCE equipment with the pinout detailed below.
DB9 Connector Pinout:
Pin Name Direction Function
1DCD Out
Used for "active" signal.
2 RD Out Serial Data Output
3 TD In Serial Data Input
4DTR In
Data Terminal Ready - may be used by Host Protocol
Driver
5 SG Signal Ground
6 DSR Out Data Set Ready - always high when unit is powered on.
7 RTS In Request to Send - may be used by Host Protocol Driver
8 CTS Out Clear to send - may be used by Host Protocol Driver
9 RI Ring indicate - not connected
_
+
DC
Load
Max 30VDC
0.5A
DIO
DIO
GND
105U-G