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VIII. LED Signals
Signal
Meaning
Repeated very short
(25 milliseconds) signals
Normal operation. It is indicator of periodical messages sending
(see Table 2 in chapter V). Interval between flashes is 500 milliseconds
by default, but can be changed by user.
Six half-second signals,
once after power on
Chart plotter presence indicator. This sentence is produced on first receiving
of
“
Datum” (PGN 129044) or “Magnetic Variation” (PGN 127258) messages.
Usually it happens within 20 seconds after chart plotter loading.
Three second signal, once
or repeatedly
Programming signals. See chapter VII for details.
Repeated 2.5 second signal
with 0.5 second interval
Device cannot claim NMEA 2000 address. Possible under special
factory tests only.
Signals with length
of 1 second or more,
from time to time
Cable is located near refrigerators, alternators or other sources of strong
electromagnetic interference. See note 1.
Constant LED signal
Sensor cable and/or sensor are damaged. See note 1.
Note 1:
Communications with the sensor are digital, data integrity is protected by a check
sum. When the Device cannot get response from the sensor, or data are invalid,
the Device turns on an LED for one second and makes the next attempt after a small
delay (less than second). If communication fails, signal time is set to 1 second again.
Therefore, communication errors produce signals of variable length, but not less than
1 second. Cable or sensor damage causes a constant LED signal.
