National Instruments NI 9467, Начало работы

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NI 9467 Overview
The NI-9467 is a stationary GPS timing module for C Series platforms. It provides
accurate timing and geographic location information to the C Series host, which
enables synchronization of C Series systems.
Start-Up Behavior
At start-up, the NI-9467 automatically begins determining its location through a
process known as self-survey. During the self-survey, the module computes a
location fix every second and averages the locations at the end to obtain a more
accurate location. After the self-survey, the NI 9467 no longer computes new
location fixes; it uses its known location and satellite signals to generate accurate
timing signals.
Like all GPS receivers, the NI-9467 requires GPS satellite ephemeris and almanac
data to compute accurate time and location. The ephemeris is detailed orbital
information about each satellite (where each satellite is expected to be at a given
time). The almanac data describes the general health of each satellite (for example,
the receiver must not use signals from satellites marked as unhealthy) and contains
coarse orbit information. The GPS satellites broadcast the ephemeris and almanac
data every 30 seconds. Therefore, it usually takes approximately 30 seconds for it to
receive the ephemeris and almanac data and start computing location and timing
fixes.
Status LED
The NI-9467 has a front panel LED to indicate status. The following table describes
the meaning of each LED pattern.
Conditions LED State
Normal operation Solid green
Performing survey Blinking green
Not enough or no satellites Blinking yellow
Antenna error (no antenna or over-current) Solid yellow
Unconfigured Off
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NI-9467 Getting Started