ELPRO 615M-1 User manual

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615M-1 Serial Client & Serial Server
The following application note demonstrates the configuration of the ELPRO 615M-1 modem utilizing the
Serial Client and Serial Server for a point to point RS232 connection. The 615M-1 supports RS232
Serial Client and Serial Server for point to point communications and also with the use of the 605M-R1
Cellular Serial Router it will allow for Point to Multipoint serial communications for up to 50 devices. This
application note only covers the point to point connection without the use of a 605M-R1 Cellular serial
router. It does not show how to provision the Cellular PPP Connection; details on this can be found in the
quick start guide for the 615M-1.
Network Example - Overview
The diagram below depicts a typical connection for a Serial Client and Serial Server connection between 2
x 615M-1 Cellular Modems. All Cellular connections must be Fixed Cellular (PPP) IP Addresses and can
be either Public or Private. This application note will explain the use of Private Fixed Cellular IP
addresses.
When looking at the configuration of the modems a Serial Client will establish a connection to the Serial
Server on a defined port. A Serial Server will never establish a connection, it will only ever accept a
connection. With this in mind typically the Serial Server will be located at a central location in the event
the configuration requires more than 1 serial client device.

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Configuration Overview
The ELPRO 615M-1 Serial configuration is located under the Serial webpage link.
At the central location (Serial Server) navigate to the serial page.
Select RS232 for Electrical Interface
Set Baud Rate, Data/Stop Bits and parity to suit
application, in this example we used 9600,8,1,N
DTR Control was left at AT&D0 which ignores
the DTR, The DTR control is used by the Client
to establish a connection to the server. Since
this modem is selected as Server it can be left
at Default of Ignore DTR.
Under the External PAD Settings select Server
and TCP for the PAD Protocol
Incoming Friendly IP address will be the remote
Modem (Serial Client) Cellular IP address.
Which can be found on the remote modems Unit
Status Page.
Incoming Port. Both the Serial Server and
Serial Client must utilize the same TCP port.
Port 5002 is used for this example.
Once this configuration is complete press
Save button at bottom of the serial webpage.

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At the Remote location this modem will be configured as the Serial Client which will establish the
connection to the Serial Server.
Select RS232 for Electrical Interface
Set Baud Rate, Data/Stop Bits and parity to
suit application, in this example we used
9600,8,1,N
This application note is demonstrating 2
PC’s connecting their terminal sessions
together, When looking at serial
communication devices there are two types
of devices DTE and DCE. PC’s are DTE
devices which by default the DTR line (Pin
4) is ON. For DTE devices change the
DTR drop down menu to be AT&D9 which
will connect to the server when DTR is ON.
When DTR is OFF a connection will not be
made or will close connection if in session.
For DCE Devices such as other Modems or
ELPRO 115S modules, DTR is OFF by
default so the setting would need to be
AT&D8 which will connect when DTR is
OFF and disconnect when DTR is ON.
Further details can be found via the help link
on the serial page.
Under the External PAD Settings select
Client and TCP for PAD Protocol.
Outgoing Port must match that of the Serial
Server. Both the Serial Server and Serial
Client must utilize the same TCP port. Port
5002 is used for this example.
Configure the Remote Host IP address with the Serial Servers Cellular IP address, which can be found on
the Unit Status page.
Enable the TCP Client Keep Alive, which will send an Alive Packet from the Client to the Server
periodically in order to detect a broken connection. The modem will automatically try to re-establish the
connection if necessary.
When the configuration is completed press the save button at the bottom of serial webpage.

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Serial Communication tests:
When both modems have been programmed confirm
under the Unit Status page of the modems that the PPP
status is UP. This indicates that there is a Cellular
connection. The PPP IP Address is the Cellular IP
Address provided from the Carrier and is the IP address
used in the Serial Page Configuration for the Incoming
Friendly IP Address and the Remote Host IP Address.
At both Serial Server and Serial Client Modems connect a straight through serial cable with
minimum Pins 2,3,4 & 5 connected. Pin 4 is the DTR Line which is required in the Client modem to
establish a connection.
When serial cables have been connected, open up a Terminal session on both PC’s, connect to
the modems and serial data should be able to be passed from one end to the other.