Xeos Alert Geomatics Resolute, Руководство пользователя

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Resolute User Manual Version 2.5 15
Device Theory of Operation
The Resolute at its heart is an embedded peripheral control unit. All enabled peripherals,
including the GNSS are controlled by a scheduler, which can be controlled by the user. Each
peripheral has three separate timer settings using the scheduler: duration, interval and offset.
Duration is the length of time the peripheral is on. Interval describes how often the device comes
on. Offset offsets the interval by the specified amount of time. Using these three parameters, the
timing of powering the peripherals can be controlled. A peripheral can be set to always on by
setting the duration to 0.
GNSS Receiver Theory of Operation
The GNSS receiver operates on the scheduler like all other peripherals. The GNSS outputs
configurable Septentrio Binary Format (SBF) blocks at a configurable rate. The Resolute can
subdivide these outputted blocks into four file ‘streams’. Individual streams are recorded to their
own files, and have the ability to record SBD blocks at different rates across streams. The files
produced from steams are individually configurable in length.
SD Cards Theory of Operation
Data written to the SD cards is initially written to circular buffers in SRAM as of firmware version
5200. SRAM buffering allows for higher data recording rates, and greater data verification. Data
is assigned a buffer based on the configuration of the data streams, with Stream 1 and 3 writing
to card 1, and Stream 2 and 4 writing to card 2.
If you wish to upgrade to firmware version 5200+ from a lower version number, please
verify you have SRAM installed on your unit by contacting Alert Geomatics.
An SRAM buffers will empty its contents to its respective SD card when the buffer reaches 70 %
full. While the file is being written to, the file is ‘open’ on the device, this makes it important to
notify the device when you are shutting it down.
Proper shut down etiquette is to either send the device a $resetnow command or to hold the
test button for 3+ seconds. Failure to do so will cause the file to be left open. Open files are
partially recoverable on a computer provided they are not written over. Files are written to the
SD card use a naming convention with an ASCII representation of BASE-36 characters with the
following name format:
SS F YY M D H.sbf
SS Two-character representation of device serial number
F Stream Source (1-4, D (Diagnostics))
YY Two-character representation of year
M Month of year
D Day of Month