General controls record

The general controls record sets general GPS operating parameters for the receiver, including the elevation mask, measurement rate, PDOP (Position Dilution of Precision) mask, and the positioning mode.

The following table shows the additional records provided when the general controls record is included with Command Packet 64h.

Byte

Item

Type

Value

Notes

0

RECORD TYPE

1 (Char)

01h

General controls record

1

RECORD LENGTH

1 (Char)

08h

Number of bytes in record, excluding bytes 0 and 1

2

ELEVATION MASK

1 (Char)

00h–5Ah

Elevation mask in degrees (0 to 90)

3

RESERVED

1 (Char)

00h

Reserved (set to zero)

4

PDOP MASK

1 (Char)

00h–FFh

Position Dilution of Precision Mask (0 to 255)

5

RESERVED

1 (Char)

00h

Reserved (set to zero)

6

RESERVED

1 (Char)

00h

Reserved (set to zero)

7

RTK POSITIONING MODE

1 (Char)

00h–01h

0 = Synchronous
1 = Low latency

8

POSITIONING SOLUTION SELECTION

1 (Char)

00h–03h

Controls use of DGPS and RTK solutions:

0: Use best available solution (recommended)
1: Produce DGPS and Autonomous solutions
2: Produce DGPS, RTK Float, and Autonomous solutions. On-the-fly RTK initialization is disabled, therefore no RTK Fix solutions are generated.
3: Produce RTK Fix, DGPS, and Autonomous solutions (no RTK Float solutions)

9

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

10

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

11

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

12

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

13

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

14

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

15

RESERVED

1 (Char)

FFh

Reserved (set to FFh)

16-19

RESERVED

4 (Float)

3Eh 99h 99h 9Ah

Reserved (set to 0.3)

20-23

RESERVED

4 (Float)

3Eh 99h 99h 9Ah

Reserved (set to 0.3)

24

RESERVED

1 (Char)

01h

Reserved (set to 01 h)

25

RESERVED

1 (Char)

00h

Reserved (set to zero)

26-27

DGNSS GPS Correction Age

2 (Short)

00h 01h – 01h 2Ch

Maximum age of correction for GPS in DGNSS solutions, valid range 1 to 300 seconds

28-29

DGNSS GLONASS Correction Age

2 (Short)

00h 01h – 01h 2Ch

Maximum age of correction for GLONASS in DGNSS solutions, valid range 1 to 300 seconds

30-31

DGNSS Galileo Correction Age

2 (Short)

00h 01h – 01h 2Ch

Maximum age of correction for Galileo in DGNSS solutions, valid range 1 to 300 seconds

32-33

DGNSS BeiDou Correction Age

2 (Short)

00h 01h – 01h 2Ch

Maximum age of correction for BeiDou in DGNSS solutions, valid range 1 to 300 seconds

34

RESERVED

1 (Char)

00h

Reserved (set to zero)

35

GLONASS Corrections Datum

1 (Char)

00h – 01h

Sets the GLONASS datum for RTCM2 corrections:

0=PZ90
1=PZ90.02

36

RESERVED

1 (Char)

00h

Reserved (set to zero)

37

Autonomous/Differential Engine mode

1 (Char)

00h – 02h

0=least-squares
1=Kalman filter
2=Kalman filter with SBAS+

38

Dynamic model

1 (Char)

??h

Dynamic model, a limited subset may be available for many receivers:

0: Kinematic (no dynamic model)
1: Human portable
2: Mapping vehicle
3: Off-road vehicle (stationary start)
4: Construction heavy equipment
5: Agriculture farm equipment
6: Airborne rotor
7: Airborne fixed wing
8: Marine
9: Rail
11: Automotive
14: Off-road vehicle (moving start)
33: Static (base station, no dynamic model)

39

Add CAN

1 (Char)

00h – 01h

0 = no CAN, COM2 with flow control
1 = add CAN, COM2 with no flow control

Only applicable in BD940 related products

40–41

RTK Propagation Time(s)

2 (Short)

00h 0Ah,
00h 14h,
00h 28h,
00h 3Ch

Low latency RTK propagation time. Current selectable values are 10, 20, 40, 60, and 120 seconds.