SENA LS110 - Manual (Page 30)

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which means the connection request is being sent. If the remote host accepts the request, the state
will be changed into [Established], which means a session has been opened. For a while, data will be
transferred between the hosts. This is [Data] state. The session will be disconnected due to the
request of one of them, which is its original state, [Closed].
2) Operations
 Serial data transfer
Whenever the serial device sends data through the serial port of the LS110, data will be
accumulated to the serial port buffer of the LS110. If the internal serial port buffer is full or inter-
character time interval reaches to the time specified as inter-character timeout value, it tries to
connect to the user-defined IP address (or domain name) of the remote host, if TCP session is
not established yet (See 4.3 Options for details on inter-character timeout). If the LS110 succeeds
in connecting to the remote host, the data in the serial port buffer will be transferred to the host.
Otherwise, all the data stored in the buffer will be cleared.
 Session disconnection
The connected session will be disconnected when the remote host sends disconnection request
or when no data transfer activity is found through the serial port for certain amount of time, which
is “Inactivity timeout” (See 4.3 Options for details on Inactivity timeout). All the data remained in
the serial port buffer will be cleared when it is disconnected.
 Connection request from remote host
All the incoming TCP connection requests will be rejected in TCP client mode.
 Cyclic Connection
It Cyclic Connection function is enabled, the LS110 will make an attempt to connect to the user-
defined remote host at certain interval even if there’s no incoming serial data from the device. If
the remote host prepares certain data, it will be transferred to the serial device via its serial port
after the connection is established. Eventually, users can monitor the serial device periodically by
making the remote host send the serial command to the LS110 whenever it is connected to the
remote host. This option is useful when users need to gather the device information periodically
even if the serial device does not send its data periodically. Figure 4-3 shows the State Transition
Diagram of the session operations in TCP client mode.