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Funk-Electronic Piciorgros GmbH
TGW-100/TGW-100R
V2.71 - Page 42 of 59
3.1.6
Using the TGW-100 as Slave Device
A TGW-100 used as slave modem need not be configured for handling a specific serial
data communication protocol. Basically, the modem passes on each data record that it
receives from a master modem out through its serial interface. When this happens, it
tags the ISSI of the master modem from which data is received, so that when it gets a
response to this data record from its local terminal equipment, it sends that response
data back to the ISSI of the master modem. Because of this procedure, a slave modem
can receive data from several master modems provided that such communications from
multiple masters does not occur at the same time.
The return address refers the slave modem to the data record of the master modem. The
response data record from the local terminal equipment is always sent back to the ISSI
of the master modem from which the last communication was received. Alternatively,
the ISSI of a specific master modem can be set in the slave modem, so that all data
received from local terminal equipment is sent only to this ISSI.
3.1.6.1
Routing SDS Data to the Primary (COM) or Secondary (AUX) Interface
The TGW-100 is equipped with two serial ports, “COM” and “AUX”. For each of these
ports, a destination port can be configured and so it can be determined whether the data
is feed from the source COM or AUX to the destination COM or AUX
If the COM routing is set to AUX, data received at the COM port will be sent to the
AUX port of the destination device.
Also if the AUX routing is set to COM, data received at the AUX port will be sent to
the COM port of the destination device.
As factory default, COM is routed to COM and AUX is routed to AUX. This feature of
using two different serial ports at the same time provides the ability to use one port for
data communication and the second port for configuration or for a second protocol if
different devices (PLC and Meter or Filed bus device) are connected to the Outstation.
Another application can use two different ports of the same device from different master
units placed also on different location.
The AUX interface is restricted, as it can not be used for RS-422, only RS-232 or RS-
485.