Installation manual

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Software setup | NSO-II Installation Manual
Diagnostics
The NMEA 2000 tab on the diagnostics page can provide information useful for identifying an
issue with the network.
Bus state simply indicates whether the bus is powered, but not necessarily connected to any
data sources. However if bus shows as ‘off ’, but power is present along with an increasing error
count, it is possible that termination or cable topology is incorrect.
Rx Overfl ows: The CAN driver got too many messages for its buff er before the application
could read them.
Rx Overruns: The CAN hardware got too many messages for its buff er before the CAN driver
could read them.
Rx/Tx Errors: These two numbers increase when there are error messages, and decrease
when messages are received successfully. These (unlike the other numbers) are not a
cumulative count. Under normal operation these should be at 0. Values around 96 upwards
indicate a heavily error prone network. If these numbers go too high for a given device, it will
automatically drop off the bus.
Fast Packet Errors: Cumulative counter of any fast packet error. This could be missed frame, or
frame out of sequence etc. NMEA 2000 PGNs are made of up to 32 frames. The entire message
will be discarded when a frame is missed.
¼ Note: The above information may not always indicate an issue that can be simply resolved
with minor adjustment to network topology or connected devices and their activity on the
network. However Rx and Tx errors are most likely indicating issues with the physical network,
which may be resolved by correcting termination, reducing backbone or drop lengths, or
reducing the number of network nodes (devices).
Ethernet setup
No special setup is required for establishing an ethernet network, it is all ‘plug and play’ .
An NEP-2 connected between an NSO-II and another network module (e.g. BSM-1) will
automatically start working, and relay data between the two devices.
Diagnostics
The UDB (User Data Base) tab on the diagnostics page, provides information on Ethernet
activity, which is presented in two tables as shown below.
Databases
The upper table gives an account of the various automatically synchronised databases that
ensure Simrad display units (NSO-II, NSS, NSE plus B&G Zeus, and Zeus Touch) are all using
the same user settings and data. Each unit stores the database locally, so that all information
is available if the device is run in standalone. Databases can become unsynchronised when
one or more displays in a multi display network are not powered up while other displays are
being operated. Creation of waypoints, routes, tracks, and altering global settings all aff ect
databases. When the tick box ‘Dirty’ is ticked, the unit has identifi ed that its database is older
than that of another device on the network. The tickbox should clear within seconds of
both devices being powered up, and the databases synchronising. If it does not clear, it is
recommended that all devices have the power cycled.
NSO-II_IM_EN_988-10392-001.indd 23 9/07/2013 3:54:23 p.m.