B.3.3 RS-232 Baud Rate
This setting specifies the baud rate of the RS-232 port. The connected device must be set to
communicate at the same baud rate.
B.3.4 RS-232 RTS
The NL241 asserts the RTS and DTR lines when doing RS-232 communications. This setting allows
the user to disable the RTS line if needed so that it will not be asserted. Some hardware will not
function if the RTS line is asserted, but typically it is not necessary to change this setting from its
default (enable).
B.3.5 RS-232 TCP Timeout
This setting will determine how fast the device will time out on the open TCP connection. For
Serial Server and MODBUS/TCP gateway configurations, the device will close the TCP connection
if no activity is detected for the timeout period. For the TCP Client configuration, the device will
close the TCP client connection if no activity is detected and then immediately open another
connection with the remote server. This behavior helps to ensure that the connection is
functional as the device does not know the frequency or nature of the expected data. Set to 0 for
no timeout (not recommended) (range 0 to 999 seconds).
B.3.6 RS-232 Always On
This setting controls whether the device is allowed to shut down the RS-232 port when it is not in
use in order to conserve power. Typically, it is not necessary to change this setting from its default
(Auto).
Auto
Based on the RS-232 port configuration, the device will decide which of the following two
modes is more likely to be desired and will operate in the according manner. If the port is
configured to TCP Serial Client, the device will choose RS-232 Always On. Otherwise, the device
will choose Power Down Port When Inactive, and it will allow the RS-232 port to power down
when not in use in order to conserve power.
Always On
The device will not power down the RS-232 port. The port will remain active always. As a result,
the processor cannot enter its lowest power state. Keeping the port Always On may be
necessary because when the RS-232 port is powered down, there is a wake-up latency and the
first few bytes that come in on the port will be missed. If this behavior is unacceptable, set this
setting to Always On to keep the RS-232 port always on.
NL241 Wireless Network Link Interface
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