Astra GAMP-2000, Справочное руководство

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1.2.9 Select Depht data
NMEA standard provides two types of information for the depth measurement:

DBT (Deep Below trasducer) that indicates the depth measured from the sensor;

DPT (Depht) that indicates the relative depth with an offset entered by the user. Usually you add, as an
offset, the immersion of the sensor in order to have the depth from the sea surface, or you can subtract
the distance that exists between the sensor and the bottom of the keel, to get an indication of the depth
below the same.
In this window you can choose what information to display and set the desired offset regardless of the settings
made on-board instrumentation.
1.2.10 Bypass the buffer (Real Time)
The real-time option bypasses the queue for a specific input. During normal operation, all incoming NMEA
sentences are stored in a queue, one for each channel, which can contain a few seconds of NMEA data. In
heavy traffic situations, these queues can be filled quite quickly until an overflow occurs. If it happens, will turn
on the red LED of the multiplexer and overflow indicators to the right of each entry section where an overflow
occurred.
Occasional overflow does not pose an immediate problem, but it just means that sometimes a NMEA
sentence in input is discarded because there is more space in the queue.
However, when a device is connected, that sends NMEA sentences 10 or 20 times per second, the
corresponding input queue in multiplexer fills constantly generating a situation of constant overflow, causing
an unacceptable delay information up to 20 seconds.
By enabling real-time option for fast entry (e.g. Gyro), its tail is bypassed, input and output is sent directly
without buffering delays the first valid NMEA sentence from the input. Some NMEA sentences are discarded
when the multiplexer is working on another entry, but this is far less problematic than having 20 seconds of
delay in information.