ProSoft Technology 5201-MNET-ASCII - Manual (Page 14)

Functional Overview MNET ♦ ProLinx Gateway
Driver Manual Modbus TCP/IP Interface Module
Page 14 of 78 ProSoft Technology, Inc.
September 1, 2010
The Server driver is able to support multiple concurrent connections from several
Clients. Up to five (5) Clients can simultaneously connect on Service Port 502
and five (5) more can also simultaneously connect on Service Port 2000. Service
Port 2001 is used by the MNET driver to pass Encapsulated Modbus commands
through from the Ethernet port to the gateway’s serial port (Modbus pass-through
support is available on 5201-MNET-MCM and 5202-MNET-MCM4 models only).
When configured as a Server, the internal database of the MNET gateway is
used as the source for read requests and the destination for write requests from
remote clients. Access to the database is controlled by the command type
received in the incoming message from the Client. The following table defines the
relationship of the gateway’s internal database to the addresses required in the
incoming Modbus TCP/IP requests:
Database Address Modbus Address
0 40001
1000 41001
2000 42001
3000 43001
3999 44000
The following virtual addresses are not part of the normal gateway user database
and are not valid addresses for standard data. However, these addresses may
be used for incoming commands that are requesting floating-point data. To use
addresses in this upper range requires you to set the Float Flag to Yes, the Float
Start to a database address in the range below, and the Float Offset to a
database address in the gateway user memory area shown above. Remember
that, once you do this, all data above the Float Start address must be floating-
point data.
Database Address Modbus Address
4000 44001
5000 45001
6000 46001
7000 47001
8000 48001
9000 49001
9999 50000
The MNET gateway must be correctly configured and connected to the network
before you attempt to use it. Use a network verification program, such as the
command prompt PING instruction, to verify that the gateway can be seen on the
network. Use ProSoft Configuration Builder to confirm proper configuration of the
gateway and to transfer the configuration files to and from the gateway.