TERSUS Precis-BX305 User manual
]
TERSUS-GNSS I
Proprietary Notice
All Information in this document is subject to change without notice and does not reflect the
commitment on Tersus GNSS. No part of this manual may be reproduced or transmitted by all
means without authorization of Tersus GNSS. The software described in this document must be
used in terms of the agreement. Any reverse software engineer or modification without permission
from Tersus GNSS is not allowed.
Revision History
Date
Major change
Version
2015-10-29
Initialization
1.0
2016-02-01
Revision
2.0
2016-07-21
Revision
3.0
2016-08-29
Revision
4.0
© Copyright 2015-2016 Tersus GNSS,
All rights reserved
]
TERSUS-GNSS II
Table of Content
1. Introduction...........................................................................................................................1
1.1. Overview......................................................................................................................1
1.2. Receiver Features.........................................................................................................1
1.3. System overview..........................................................................................................2
1.4. Electronic Characteristics.............................................................................................3
1.4.1. Absolute Maximum Ratings ....................................................................................3
1.4.2. Operation Ratings ....................................................................................................4
1.4.3. Port Description (Precis-BX305 V1.1 & V2.0) .......................................................5
1.4.3.1. Micro_USB Power Supply Port...............................................................................8
1.4.3.2. COM1/COM2 Port...................................................................................................8
1.4.3.3. LED Indicator ........................................................................................................10
1.4.3.4. SMA1 Port.............................................................................................................10
1.4.3.5. SMA2 Port.............................................................................................................10
1.4.3.6. USB Port................................................................................................................11
1.5. Accessories and connection .......................................................................................11
1.5.1. UART_To_USB Converter Module.......................................................................11
1.5.2. Data Logger Module and Cable.............................................................................12
1.5.3. Pixhawk Cable .......................................................................................................13
1.5.4. Radio Module and Cable........................................................................................14
1.5.5. Bluetooth Module and Cable .................................................................................15
2. Setting up the Receiver .......................................................................................................17
2.1. Connect to Computer .................................................................................................17
2.2. Connect to Antenna....................................................................................................18
2.3. Connect to Base Station .............................................................................................19
2.3.1. Connect to Base Station with UHF radio module..................................................20
2.3.2. Connect to CORS with external Bluetooth module and mobile phone..................22
2.4. Integration with Autopilots.........................................................................................25
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TERSUS-GNSS III
2.5. Set up Base Station.....................................................................................................27
2.5.1. Obtain the coordinate of the base station...............................................................27
2.5.2. Antenna installation ...............................................................................................28
2.5.3. Observation environment.......................................................................................28
2.6. Log Data to SD Card..................................................................................................28
2.6.1. Hardware and software required............................................................................29
2.6.2. Configuring raw observation output ......................................................................29
2.6.3. Connect to data logger ...........................................................................................30
2.6.4. Export logged data and format conversion ............................................................31
2.7. Installation and Operation Guideline .........................................................................31
2.7.1. ESD protection.......................................................................................................31
2.7.2. Avoid signal inference............................................................................................32
3. Commands description........................................................................................................33
3.1. Overview of Command System .................................................................................33
3.2. Serial Port Control Commands ..................................................................................33
3.2.1. Configuring serial port baud rate (COM)...............................................................33
3.2.2. Configuring serial port mode (INTERFACEMODE) ............................................34
3.2.3. Display current serial port configuration (LOG COMCONFIG)...........................34
3.3. Satellite Control Commands ......................................................................................35
3.3.1. Controlling satellite system (SYSCONTROL)......................................................35
3.3.2. Set elevation mask (ECUTOFF) ............................................................................35
3.4. Station Coordinate Control Commands .....................................................................35
3.4.1. Fix base station coordinate (FIX POSITION)........................................................36
3.4.2. Cancelling fixed coordinate (FIX NONE).............................................................36
3.4.3. Choose undulation (UNDULATION)....................................................................36
3.5. Output Control Commands ........................................................................................37
3.5.1. NMEA talker configuration (NMEATALKER) .....................................................37
3.5.2. Configuring NMEA output (LOG NMEA)............................................................37
3.5.3. Configuring raw observation output (LOG RANGECMPB).................................37
3.5.4. Configuring GPS ephemeris output (LOG GPSEPHEMB)...................................38
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TERSUS-GNSS IV
3.5.5. Configuring GLONASS ephemeris output (LOG GLOEPHEMRISB).................38
3.5.6. Configuring Beidou Ephemeris output (LOG BD2EPHEMB)..............................38
3.5.7. Configuring RTCM2 output (LOG RTCM)...........................................................39
3.5.8. Configuring RTCM 3 output (LOG RTCM3)........................................................39
3.6. Version Information Commands (LOG VERSION) ..................................................40
3.7. Configuration Management Commands ....................................................................40
3.7.1. Saving configurations (SAVECONFIG)................................................................40
3.7.2. Reset to factory mode (FRESET) ..........................................................................41
3.7.3. Check logged message types..................................................................................41
3.8. Configuring PPS output .............................................................................................42
3.9. Output Cancellation Commands ................................................................................42
3.9.1. Cancelling particular output (UNLOG) .................................................................42
3.9.2. Cancelling all output (UNLOGALL).....................................................................43
4. Specifications......................................................................................................................44
4.1. Performance Specification .........................................................................................44
4.2. Physical Specification ................................................................................................45
5. Output Format.....................................................................................................................46
5.1. NMEA Sentences.......................................................................................................46
5.1.1. General sentence format.........................................................................................46
5.1.2. GGA sentence ........................................................................................................46
5.1.3. RMC sentence........................................................................................................47
5.1.4. VTG sentence.........................................................................................................48
5.1.5. GSA sentence.........................................................................................................48
5.1.6. GSV sentence.........................................................................................................49
5.2. RTCM Messages........................................................................................................49
5.2.1. RTCM 2 messages .................................................................................................49
5.2.2. RTCM 3 messages .................................................................................................50
6. RTK Configure Example.....................................................................................................52
7. Trouble Shooting.................................................................................................................53
8. Terminology........................................................................................................................54
]
TERSUS-GNSS V
]
TERSUS-GNSS VI
List of Figures
Figure 1 Outlook of Precis-BX305 Board.........................................................................................1
Figure 2 System block diagram.........................................................................................................2
Figure 3 Port Description of Precis-BX305......................................................................................5
Figure 4 Identify Precis-BX305 V1.1 & V2.0 and Pin Definitions ..................................................6
Figure 5 Identify Precis-BX305 V1.1 & V2.0 by Printed Labels.....................................................7
Figure 6 Schematic of Internal Micro_USB Connector....................................................................8
Figure 7 Back Panel View of Precis-BX305 Board..........................................................................8
Figure 8 Labels of Precis-BX305 V1.1 & V2.0 UART_To_USB Converter Cables......................11
Figure 9 Connection between Precis-BX305 and UART_to_USB Converter................................12
Figure 10 Labels of Precis-BX305 V1.1 & V2.0 Data logger Cables.............................................12
Figure 11 Connection between Precis-BX305 and UART_to_Data Logger...................................13
Figure 12 Labels of Precis-BX305 V1.1 & V2.0 Pixhawk Cables .................................................13
Figure 13 Connection between Pixhawk and Precis-BX305 ..........................................................14
Figure 14 Labels of Precis-BX305 V1.1 & V2.0 Radio Cables......................................................14
Figure 15 Connection between Pixhawk and Precis-BX305 ..........................................................15
Figure 16 Labels of BX305 V1.1 & V2.0 Bluetooth Cables...........................................................15
Figure 17 Connection between Bluetooth module and Precis-BX305............................................16
Figure 18 Demonstration of wired connection to computer............................................................17
Figure 19 Demonstration of Precis board in Window device manager...........................................18
Figure 20 Recommended GNSSAntenna for Precis-BX305..........................................................19
Figure 21 Three ways to connect to the base station data stream: wired connection (upper), UHF
connection (middle) ........................................................................................................................19
Figure 22 Overview of Tersus GNSS RTK Systems.......................................................................20
Figure 23 Establish Serial Connection with Tersus GNSS Center..................................................21
Figure 24 Text Console Window of Tersus GNSS Center ..............................................................22
Figure 25 Demonstration of connecting Precis BX305 to CORS Network....................................23
Figure 26 Demonstration of connecting Bluetooth module, mobile phone, Precis-BX305 and
supply supplier................................................................................................................................24
Figure 27 Example of NTRIP Settings............................................................................................25
Figure 28 Demonstration of Connection Status..............................................................................25
Figure 29 Demonstration of Integration with Pixhawk autopilot....................................................26
Figure 30 Precis-BX305 board is recognized by Pixhawk and Mission Planner............................27
Figure 31 Demonstration of antenna height measurement..............................................................28
Figure 32 External data logger........................................................................................................29
Figure 33 Enter commands for logging raw observation and broadcasting ephemeris data...........30
Figure 34 Connection of Precis-BX305, external data logger and power supplier.........................31
]
TERSUS-GNSS VII
List of Tables
Table 1 Description of Absolute Maximum Ratings.........................................................................3
Table 2 Description of Operation Ratings.........................................................................................4
Table 3 Description of Precis-BX305 Electronic Interfaces .............................................................7
Table 4 Pin list of Precis-BX305 V1.1 COM1 and COM2 Port........................................................8
Table 5 Pin definition of Precis-BX305 V1.1 COM1 and COM2 Port.............................................9
Table 6 Pin list of Precis-BX305 V2.0 COM1 and COM2 Port........................................................9
Table 7 Pin list of Precis-BX305 V2.0 COM1 and COM2 Port......................................................10
Table 8 Definition of LED indicators..............................................................................................10
Table 9 PPS signal Description.......................................................................................................11
Table 10 Default Serial port parameter of Precis-BX305 COM1 and COM2.................................18
Table 11 Pin definition of Pixhawk GPS port (from left to right)...................................................26
Table 12 Configuring serial port baud rate command.....................................................................33
Table 13 Change serial port mode...................................................................................................34
Table 14 Serial port mode...............................................................................................................34
Table 15 Display current serial port configuration..........................................................................34
Table 16 enable/disable satellite system..........................................................................................35
Table 17 Set elevation mask............................................................................................................35
Table 18 Fix the coordinate of the base station...............................................................................36
Table 19 Cancel the fixed coordinate..............................................................................................36
Table 20 Sets ellipsoid-geoid separation.........................................................................................36
Table 21 change the NMEAtalker during NMEA output...............................................................37
Table 22 log nmea message.............................................................................................................37
Table 23 Log compressed binary version of observation data........................................................38
Table 24 Configuring GPS ephemeris output..................................................................................38
Table 25 Configuring GLONASS ephemeris output ......................................................................38
Table 26 Configuring Beidou Ephemeris output.............................................................................39
Table 27 log observations in RTCM2.X format..............................................................................39
Table 28 log observations in RTCM3 information..........................................................................39
Table 29 Display version information.............................................................................................40
Table 30 Save current configuration ...............................................................................................41
Table 31 reset to factory mode........................................................................................................41
Table 32 Check logged message types............................................................................................41
Table 33 Check logged message types............................................................................................42
Table 34 Cancel a particular output.................................................................................................42
Table 35 Cancell all output .............................................................................................................43
Table 36 Performance specification of Precis-BX305 ....................................................................44
Table 37 Physical Specification of Precis-BX305 ..........................................................................45
]
TERSUS-GNSS 1
1. Introduction
1.1. Overview
The Precis-BX305 board provides millimeter level carrier phase observation as well as centimeter
level RTK positioning accuracy. It also supports chip level multi path mitigation, RTK positioning
and instant heading technology, especially suitable for high accuracy navigation and positioning
used in moving objects like cars, unmanned aerial vehicles(UAV) etc. it also applies for the control
of agriculture machinery, engineering machinery and port machinery, as well as displacement
measurement and GIS etc.
Figure 1 Outlook of Precis-BX305 Board
1.2. Receiver Features
■Support GPS L1/L2, GLONASS L1, and Beidou B1/B3;
■Support single satellite system positioning and multi-system positioning;
■Support sub-meter RTD positioning and centimeter level RTK positioning;
■Support log raw observations.
■Support 2 UART(COM)s and 1 PPS(Pulse Per Second accuracy timing); High reliability
and stability even in harsh environment;
■Update rate up to 20Hz;
■Powered by +5V micro USB power supply;
■Onboard 6DOF IMU, support integrated navigation system (INS).
]
TERSUS-GNSS 2
1.3. System overview
Precis block diagram is presented as follows
IO
INS
GNSS
demodulator
Daughter board
MCU
Mother board
RF
Figure 2 System block diagram
RF module: Receives GNSS signals from antenna, sends to baseband module as IF signal after
filtering and low noise amplifying.
Baseband: Demodulates GNSS IF signals into navigation message.
MPU: A microprocessor for PVT calculation, differential position processing, and data transfer to
and from peripherals.
INS: INS integrates an IMU with 3-axis accelerometer, a 3-axis gyroscopes and a 3-axis magnetic
sensor, can provide motion tracking information under obstacles environment where GNSS signal
is lost.
IO: Includes COMs, LED and power supply etc. interface.
]
TERSUS-GNSS 3
1.4. Electronic Characteristics
1.4.1. Absolute Maximum Ratings
Table 1 Description of Absolute Maximum Ratings
Note
damage. These are stress ratings only. The product is not protected against overvoltage or reversed
voltages. If necessary, voltage spikes exceeding the power supply voltage specification, given in
table above, must be limited to values within the specified boundaries by using appropriate
protection diodes.
Parameter
Symbol
Condition
Min
Max
Unit
Power Supply Voltage (From
Micro-USB)
Vin
6
V
Input pin applied DC Voltage
RXD_UART
3.6
V
Vin_USB
3.6
V
Vrfin
0
V
DC current trough any digital
I/O pin (except supplies)
Ipin
10
mA
Input power at RF_IN
Prfin
Source
impedance =
continuous
wave
13
dBm
Antenna bias voltage
V_ANT
6
V
Antenna bias current
I_ANT
100
mA
Storage temperature
Tstg
-40
85
°C
]
TERSUS-GNSS 4
1.4.2. Operation Ratings
Table 2 Description of Operation Ratings
Parameter
Symbol
Condition
Min
Typ
Max
Unit
Power Supply Voltage
(From Micro-USB)
Vin_USB
5
V
Power Consumption
(Total)
Ptol
3.5
W
Digital IO Pin Low
level input voltage
RXD_UART,
TXD_UART
0
0
0.66
V
Digital IO Pin High
level input voltage
RXD_UART,
TXD_UART
2.3
3.3
V
Digital IO Pin Low
level output voltage
RXD_UART,
TXD_UART,
PPS
Iol = 4 mA
0
0.4
V
Digital IO Pin High
level output voltage
RXD_UART,
TXD_UART,
PPS
Iol = 4 mA
2.9
3.3
V
Output Power voltage
(VCC_3V3)
Vout
3.135
3.3
3.465
V
Output Power current
(VCC_3V3)
Iout
200
mA
V_ANT antenna bias
voltage
V_ANT
4.75
5.1
V
Antenna bias voltage
drop
V_ANT_DR
OP
0.1
13
dBm
Antenna bias current
I_ANT
100
mA
RF Input Level
Prf
-105
-85
dBm
RF Signal Type
GNSS
Beido B1/B3, GPS L1/L2, GLONASS L1
Receiver Chain Noise
Figure
NF_tol
3.5
dB
Operation
temperature
Topt
-40
85
°C
Note: All specifications are at an ambient temperature of 25°C. Extreme operating temperatures
can significantly impact specification values. Applications operating near the temperature limits
should be tested to ensure the specification.
]
TERSUS-GNSS 5
Note：The serial port definitions of the serial ports are different for different version of mother
board design. There are two version of mother board: v1.1 and v2.0. The version information has
been marked on the receivers (see Figure 4). The pin definition of the serial port for v1.1 and v2.0
are listed respectively (see Table 4 to 7). Please pay attention to this particular issue if you intend
to use your own cable. If you have any problems in operation, please feel free to contact us at
sales@tersus-gnss.com.
1.4.3. Port Description (Precis-BX305 V1.1 & V2.0)
Figure 3 Port Description of Precis-BX305
Note: The difference between Precis-BX305 V1.1 and Precis-BX305 V2.0 are pin definition in
COM1 and COM2 ports. The pin descriptions of V1.1 and V2.0 COM1 and COM2 are labeled
independently at the back of Precis-BX305 (See Figure 4).
]
TERSUS-GNSS 6
Figure 4 Identify Precis-BX305 V1.1 & V2.0 and Pin Definitions
Note: No labels on Precis-BX305 receivers and accessory cables before August 2016, the product
version could be found on the top left corner of Precis-BX305 (See Figure 5).
]
TERSUS-GNSS 7
Figure 5 Identify Precis-BX305 V1.1 & V2.0 by Printed Labels
Table 3 Description of Precis-BX305 Electronic Interfaces
Interfaces
Descriptions
COM1
5pin PicoBlade receptacle connector with LVTTL voltage level
COM2
5pin PicoBlade receptacle connector with LVTTL voltage level
LED
Indicate running status
Host USB port
Not available
Micro USB
5V DC power supply
SMA1
For GNSS RF Input
SMA2
For PPS output
]
TERSUS-GNSS 8
1.4.3.1. Micro_USB Power Supply Port
BX305 could be powered by three ports. One is Micro_USB port, and the other two are VIN pins
in COM1 and COM2 port. (Note: The VIN pins in the three ports could not be connected to
different power supply contemporary. Or not, the board will be damaged.)
At the Micro_USB port, only VBUS and GND Pin are connected. VBUS Pin is for the whole
Receiver Box power supply. And the supply voltage range is from 4.3V~ 6.0V. The internal circuit
of the port is as Figure 6.
Figure 6 Schematic of Internal Micro_USB Connector
1.4.3.2. COM1/COM2 Port
Please note the difference between Precis-BX305 V1.1 and Precis-BX305 V2.0).
The following are the back panel of Precis-BX305 V1.1/V2.0.
3
4
1
2
COM1 COM2
:pin1
:pin 2,3,4,5 from left to right
Figure 7 Back Panel View of Precis-BX305 Board
■Precis-BX305 V1.1 COM1 and COM2 port pin list and pin definition
Table 4 Pin list of Precis-BX305 V1.1 COM1 and COM2 Port
Pin1
Pin2
Pin3
Pin4
Pin5
COM1
VIN
VCC_3V3
TxD1
RxD1
GND
COM2
VIN
VCC_3V3
RxD2
TxD2
GND
]
TERSUS-GNSS 9
Table 5 Pin definition of Precis-BX305 V1.1 COM1 and COM2 Port
Port
Pin number
Name
I/O
Description
COM1
PIN1
VIN
I
Input Power Supply for the whole BOX. The voltage range is
from 4.3V~6.0V
PIN2
VCC_3V3
O
Output Power Supply for the accessories. The voltage range is
from 3.3V
PIN3
TxD1
O
UART1 Tx. 3.3V LVTTL type.
PIN4
RxD1
I
UART1 Rx. 3.3V LVTTL type.
PIN5
GND
-
Ground
COM2
PIN1
VIN
I
Input Power Supply for the whole BOX. The voltage range is
from 4.3V~6.0V
PIN2
VCC_3V3
O
Ouput Power Supply for the accessories. The voltage range is
from 3.3V
PIN3
RxD2
I
UART2 Rx. 3.3V LVTTL type.
PIN4
TxD2
O
UART2 Tx. 3.3V LVTTL type.
PIN5
GND
-
Ground
■Precis-BX305 V2.0 COM1 and COM2 port pin list and pin definition
Table 6 Pin list of Precis-BX305 V2.0 COM1 and COM2 Port
Port
Pin1
Pin2
Pin3
Pin4
Pin5
COM1
GND
RxD1
TxD1
VCC_3V3
VIN
COM2
GND
RxD2
TxD2
VCC_3V3
VIN
]
TERSUS-GNSS 10
Table 7 Pin list of Precis-BX305 V2.0 COM1 and COM2 Port
COM1
PIN1
GND
-
Ground
PIN2
RxD1
I
UART1 Rx. 3.3V LVTTL type.
PIN3
TxD1
O
UART1 Tx. 3.3V LVTTL type.
PIN4
VCC_3V3
O
Ouput Power Supply for the accessories. The voltage range is from
3.3V
PIN5
VIN
I
Input Power Supply for the whole BOX. The voltage range is from
4.3V~6.0V
COM2
PIN1
GND
-
Ground
PIN2
RxD2
I
UART2 Rx. 3.3V LVTTL type.
PIN3
TxD2
O
UART2 Tx. 3.3V LVTTL type.
PIN4
VCC_3V3
O
Outddput Power Supply for the accessories. The voltage range is
from 3.3V
PIN5
VIN
I
Input Power Supply for the whole BOX. The voltage range is from
4.3V~6.0V
1.4.3.3. LED Indicator
The LED indicators show the operational status of Precis-BX305 board. The functions of these
indicators are defined in Table 8. The Precis-BX305 performs self-check and initialization
procedure before it starts work. If you are in trouble, please go to chapter 7 for trouble shooting.
Table 8 Definition of LED indicators
LED1
LED2
LED3
LED4
Reserved
Reserved
Positioning status
Power indicator
1.4.3.4. SMA1 Port
The SMA1 connector receives GNSS RF signal and contemporary supplies 5V voltage for the
LNA in the active GNSS Antenna. The current is limited to 100mA. For details of the RF signal
and Antenna Bias voltage and current, please refer to Table 2.
1.4.3.5. SMA2 Port
PPS output signal from SMA2 connector is 3.3V LVTTL signal. The following table is the details
of the signal description.About the electronics details, please refer to Table 2.
]
TERSUS-GNSS 11
Table 9 PPS signal Description
Signal
Input/Output
Factory
Default
Comment
PPS
Output
Active Low
High voltage is 3.3V and IO type is LVTTL.A time synchronization
output. This is a pulse where the leading edge is synchronized to
receiver-calculated GNSS Time. The polarity, period and pulse width
can be configured using
PPSCONTROL command
1.4.3.6. USB Port
USB port is not available in V_1.1 and V_2.0.
1.5. Accessories and connection
There are two types of cables for Precis-BX305. One is for Precis-BX305 V1.1 and the other is for
Precis-BX305 V2.0. The version and the pin definition are labeled on the cables.
1.5.1. UART_To_USB Converter Module
connector should be connected to BX305 COM1, and the USB type a connector could be inserted
to PC or Laptop. The following are the pin definition of the two versions.
Figure 8 Labels of Precis-BX305 V1.1 & V2.0 UART_To_USB Converter Cables
Other manuals for Precis-BX305
1
Table of contents
