Microchip Technology GPS-2700, User Manual

Page: 39 / 77

SCPI-Control Quick Start Instructions
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2020 Microchip Technology Inc. DS50003016A-page 39
3.3.18 GPS:DYNAM:MODE 8 (Automatic Dynamic Mode)
Automatic Dynamic Mode allows the GPS-2700 firmware to automatically configure the
GNSS receiver Kalman filter parameters based on actual mission velocities and motion
profiles. The unit will try to set the GNSS receiver to the optimal setting for any given
velocity. The unit is able to set 7 different modes, as shown in
Section 3.3.17 “GPS:DYNAM:MODE <int> [0,7]” .
The following table shows the Dynamic mode the unit will program into the GNSS
receiver when Automatic Mode is selected (Dynamic Mode 8).
TABLE 3-3: AUTO DYNAMIC MODE SWITCHING RULES
Velocity Threshold Selected Dynamic Model Fallback to Lower Setting
0 – 2 knots Stationary None
>2 knots Pedestrian <1 knots
>10 knots Automotive <8 knots
>60 knots and >400 Feet/min
climb/descent
Airborne 1g <50 knots
>150 knots Airborne 2g <130 knots
>240 knots Airborne 4g <210 knots
In this Automatic mode, the unit will configure the GNSS receiver based on the actual
vehicle-velocity:
Please note that in order to switch from the Automotive mode into the first Airborne (1g)
mode, both a vehicle velocity greater than 60 knots as well as a climb/descent rate
greater than 400 feet per minute are required. Alternatively, a vehicle velocity of greater
than 100 knots will also initiate a switch into airborne-1g mode.
Without an appropriate climb/descent, the unit will remain in Automotive mode.
The following command returns the setting of the GNSS dynamic model:
GPS:DYNAM:MODE?
The actual state chosen by the firmware for the GNSS receiver based on vehicle veloc-
ity can be obtained with the command:
GPS:DYNAM:STAT?
A value between 0 and 7 is then returned depending on vehicle dynamics.
The dynamic state is always set to STATIONARY if one of the Position Hold Auto Sur-
vey stationary modes is selected using the command GPS:TMODE, as the Position
Hold mode setting overrides any dynamic state user setting.
Settings will be applied immediately to the GNSS receiver, and are stored in Non Vol-
atile memory.
3.3.19 GPS:DYNAM:STAT?
This query returns the actual state of the dynamic model, chosen by the firmware to be
applied to the GNSS receiver depending on vehicle velocity. It returns a value between
0 and 7, which correspond to one of the dynamic models defined in
Table 3-3 .
This state can be different from the user-selected Dynamic model mode for two rea-
sons:
• If the dynamic mode is set to 8 (Automatic mode), the state will reflect the
dynamic model being applied to the GNSS receiver depending on actual vehicle
dynamics.
• If the GNSS Timing Mode is set to ON or to RSTSURV, the dynamic state will
always be set to 1 (Stationary).