Power Down Port when Inactive
The device will power down RS-232 when the port is inactive. If the device is configured for
Serial Server mode, the inactivity timeout is 40 seconds. If configured for PakBus, the device
can use the PakBus protocol link-state to do a more intelligent and effective inactivity timeout.
If communications are received on the port after it has been powered down, there is a wake-up
latency and the first few bytes will be missed. PakBus has a built-in mechanism to deal with
this, but if the device is not configured for PakBus communications, the user must decide if the
application can accept this behavior. If this behavior is unacceptable, set this setting to Always
On. The power savings that the device is able to achieve by powering down the RS-232 port are
significant as the processor is also able to go to a deeper sleep mode. In an idle state with Low
Power Mode enabled, an additional ~0.12W savings are observed by setting RS-232 Always On
to Power Down Port when Inactive.
B.3.7 RS-232 PakBus Beacon Interval
This setting, in units of seconds, governs the rate at which the NL241 will broadcast PakBus
messages on the RS-232 port in order to discover any new PakBus neighboring nodes. It will also
govern the default verification interval if the value of the RS -232 PakBus Verify Interval setting
for the associated port is 0.
B.3.8 RS-232 PakBus Verify Interval
This setting specifies the interval, in units of seconds, that will be reported as the link verification
interval in the PakBus hello-transaction messages. It will indirectly govern the rate at which the
NL241 will attempt to start a hello transaction with a neighbor if no other communications has
taken place within the interval.
B.3.9 Neighbors Allowed RS-232
This setting specifies the explicit list of PakBus node addresses that the NL241 will accept as
neighbors on the RS-232 port. If the list is empty (the default value), any node will be accepted as
a neighbor. This setting will not affect the acceptance of a neighbor if that neighbor address is
greater than 3999. The formal syntax for this setting follows:
neighbor : = { "(" range-begin "," range-end ")" }.
range-begin : = pakbus-address. ;
range-end : = pakbus-address.
pakbus-address : = number. ; 0 < number < 4000
Example: (129,129) (1084,1084)
In the example above, nodes 129 and 1084 are assigned as neighbors to the NL241.
NL241 Wireless Network Link Interface
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