User manual

Chapter Three Operation
Page 47 March 2010
Enable RS-232 PPP Server Check this box to enable the PPP network server on the RS-232 port.
Enable RS-485 Serial
Gateway
Check this box to enable the Serial Gateway Server on the RS-485 port.
Data Rate The serial data rate desired. Serial data rates available range from
110bps to a maximum of 38,400 b/s.
Data Bits Parity Stop Bits The data format desired. Data formats of 8N1, 7E1, 7O1, 7E2, 7O2 are
supported.
Character Timeout Enter the maximum delay (in msec) between received serial characters
before packet is sent via network.
Server When configured as Server, the module will wait for a connection to be
initiated by a remote client
Listen Port Server Only. Enter the TCP port number on which the server must listen
for incoming connections. The standard TELNET port is 23.
Client When configured as Client, the module will automatically attempt to
connect to the specified remote server
Remote Device Port Client only. Enter the TCP port number of the remote server (i.e. the
remote port to automatically connect to).
Remote Device IP Address Client only. Enter the IP Address of the remote server (i.e. the remote IP
Address to automatically connect to).
3.12.3 ModBus TCP to RTU Server
The ModBus TCP to RTU Server allows an Ethernet ModBus/TCP Client (Master) to
communicate with a serial ModBus RTU Slave. The WI-MOD-9-E makes this possible by
internally performing the necessary protocol conversion. The conversion is always performed by
the WI-MOD-9-E which is directly connected to the ModBus serial device (i.e. only this module
needs to have ModBus TCP to RTU Server enabled).
The above example demonstrates how a ModBus/TCP Client (Master) can connect to one or
more ModBus RTU (i.e. serial) Slaves. In this example the WI-MOD-9-E Access Point is
configured with the “RS232 ModBus/TCP to RTU Gateway” enabled. Once enabled, the
gateway converts the ModBus/TCP queries received from the Master into ModBus RTU queries
and forwards these over the RS232 port to the Slave. When the serial response to the query
arrives from the Slave, it is converted to a ModBus/TCP response and forwarded via the network