Campbell NL240, Инструкция по эксплуатации

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Appendix C. NL240 Settings
unacceptable, set this setting to “Always On” to keep the RS-232 port
always on.
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’s 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.”
RS-232 PakBus Beacon Interval
This setting, in units of seconds, governs the rate at which the NL240 will
broadcast PakBus® messages on the associated port in order to discover any
new PakBus neighboring nodes. It will also govern the default verification
interval if the value of the Verify Interval setting for the associated port is zero.
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 NL240 will attempt to start a hello
transaction with a neighbor if no other communication has taken place within
the interval.
Neighbors Allowed RS-232
Example: (129,129) (1084,1084)
In the example above, nodes 129 and 1084 are assigned as neighbors to the
NL240.
This setting specifies, for a given port, the explicit list of PakBus node
addresses that the NL240 will accept as neighbors. 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's 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
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