L76 Series
EVB User Guide
GNSS Module Series
Version: 2.1
Date: 2021-08-05
Status: Released
GNSS Module Series
Our aim is to provide customers with timely and comprehensive service. For any assistance,
contact our company headquarters:
Quectel Wireless Solutions Co., Ltd.
Building 5, Shanghai Business Park Phase III (Area B), No.1016 Tianlin Road, Minhang District, Shanghai
200233, China
Tel: +86 21 5108 6236
Email: info@quectel.com
Or our local office. For more information, visit:
http://www.quectel.com/support/sales.htm.
For technical support, or to report documentation errors, visit:
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Or send an email to support@quectel.com.
General Notes
Quectel offers the information as a service to its customers. The information provided is based upon
customers’ requirements. Quectel makes every effort to ensure the quality of the information it makes
available. Quectel does not make any warranty as to the information contained herein, and does not accept
any liability for any injury, loss or damage of any kind incurred by the use of or reliance upon the information.
All information supplied herein is subject to change without prior notice.
Disclaimer
While Quectel has made efforts to ensure that the functions and features under development are free from
errors, it is possible that these functions and features could contain errors, inaccuracies and omissions.
Unless otherwise provided by valid agreement, Quectel makes no warranties of any kind, implied or
express, with respect to the use of features and functions under development. To the maximum extent
permitted by law, Quectel excludes all liability for any loss or damage suffered in connection with the use
of the functions and features under development, regardless of whether such loss or damage may have
been foreseeable.
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for any noncompliance with the above requirements, unauthorized use, or other illegal or malicious use of
the documentation and information.
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Copyright
The information contained here is proprietary technical information of Quectel. Transmitting, reproducing,
disseminating and editing this document as well as using the content without permission is forbidden.
Offenders will be held liable for payment of damages. All rights are reserved in the event of a patent grant
or registration of a utility model or design.
Copyright © Quectel Wireless Solutions Co., Ltd. 2021. All rights reserved.
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GNSS Module Series
Safety Information
The following safety precautions must be observed during all phases of operation, such as usage, service
or repair of any terminal incorporating Quectel L76-LB module. Manufacturers of the terminal should send
the following safety information to users and operating personnel, and incorporate these guidelines into all
manuals supplied with the product. Otherwise, Quectel assumes no liability for customers’ failure to comply
with these precautions.
Ensure that the product may be used in the country and the required environment,
as well as that it conforms to the local safety and environmental regulations.
Keep away from explosive and flammable materials. The use of electronic products
in extreme power supply conditions and locations with potentially explosive
atmospheres may cause fire and explosion accidents.
The product must be powered by a stable voltage source, while the wiring must
conform to security precautions and fire prevention regulations.
Proper ESD handling procedures must be followed throughout the mounting,
handling and operation of any devices and equipment that incorporate the module
to avoid ESD damages.
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GNSS Module Series
About the Document
Document Information
Title
L76 Series EVB User Guide
Subtitle
GNSS Module Series
Document Type
EVB User Guide
Document Status
Released
Revision History
Version
Date
Description
1.0
2013-02-25
Initial
1.1
2013-03-26
Optimized the contents of Chapter 3.
2016-05-03
1. Changed the document name from Quectel_L76_EVB_User_Guide to
Quectel_L76_Series_EVB_User_Guide.
2. Incorporated the related information of L76-L.
2021-08-05
1. Added the applicable module L76-LB.
2. Updated the overall structure of the document, including but not limited
to the adding of Chapters 4, 5 and 6.
2.0
2.1
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GNSS Module Series
Contents
Safety Information ...................................................................................................................................... 3
About the Document .................................................................................................................................. 4
Contents ...................................................................................................................................................... 5
Table Index .................................................................................................................................................. 6
Figure Index ................................................................................................................................................ 7
1
Introduction ......................................................................................................................................... 8
2
General Overview ................................................................................................................................ 9
2.1. EVB Kit Accessories .................................................................................................................. 9
2.2. Connecting Cables and Antenna to EVB ................................................................................. 10
3
Board User Interfaces....................................................................................................................... 11
3.1. EVB Top View............................................................................................................................ 11
3.2. Board User Interfaces ............................................................................................................... 11
4
Using QCOM Tool to Communicate ................................................................................................ 14
4.1. Communication via the Micro-USB Interface........................................................................... 14
5
Using QGNSS Tool to Test............................................................................................................... 16
5.1. COM Port and Baud Rate Setting ............................................................................................ 16
5.1.1. Interface Explanation .................................................................................................... 17
5.2. TTFF Testing ............................................................................................................................ 19
5.3. AGNSS Setting ........................................................................................................................ 21
5.3.1. Assistant GNSS Online ................................................................................................. 21
5.3.2. Assistant GNSS Offline ................................................................................................. 23
6
Using QGPSFlashTool to Upgrade Firmware ................................................................................ 27
7
Appendix References ....................................................................................................................... 30
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Table Index
Table 1: List of Accessories ........................................................................................................................ 10
Table 2: Detailed EVB Interfaces ............................................................................................................... 12
Table 3: J106 Pin Detailed Description ...................................................................................................... 13
Table 4: Explanation of QGNSS Interface ................................................................................................. 17
Table 5: Related Documents ...................................................................................................................... 30
Table 6: Terms and Abbreviations .............................................................................................................. 30
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Figure Index
Figure 1: EVB Kit Accessories ..................................................................................................................... 9
Figure 2: EVB and Accessories Assembly ................................................................................................. 10
Figure 3: EVB Top View ..............................................................................................................................11
Figure 4: USB Port ..................................................................................................................................... 14
Figure 5: COM Port Setting Interface of QCOM ........................................................................................ 14
Figure 6: NMEA Sentences Output by Module – Displayed on QCOM Tool Interface .............................. 15
Figure 7: QGNSS Setting ........................................................................................................................... 16
Figure 8: QGNSS Interface (Connected) ................................................................................................... 17
Figure 9: Static TTFF Testing via QGNSS ................................................................................................. 19
Figure 10: TTFF Test Settings .................................................................................................................... 19
Figure 11: AGNSS Setting .......................................................................................................................... 20
Figure 12: Run or Stop Test ....................................................................................................................... 20
Figure 13: Test Results............................................................................................................................... 21
Figure 14: AGNSS Setting via QGNSS – Assistant GNSS Online ............................................................ 21
Figure 15: Assistant GNSS Online Setting................................................................................................. 22
Figure 16: Connect and Download – AGNSS Online ................................................................................ 22
Figure 17: Download Selected File – AGNSS Online ................................................................................ 23
Figure 18: Successfully Downloaded to the Module – AGNSS Online...................................................... 23
Figure 19: AGNSS Setting via QGNSS - Assistant GNSS Offline ............................................................. 24
Figure 20: Assistant GNSS Offline Setting................................................................................................. 24
Figure 21: Connect and Download – AGNSS Offline ................................................................................ 25
Figure 22: Download Selected File – AGNSS Offline ................................................................................ 25
Figure 23: Successfully Downloaded to the Module – AGNSS Offline...................................................... 26
Figure 24: Firmware Upgrade – Step 1...................................................................................................... 27
Figure 25: Firmware Upgrade – Step 2...................................................................................................... 28
Figure 26: Firmware Upgrade – Step 3...................................................................................................... 28
Figure 27: Firmware Upgrade – Step 4...................................................................................................... 29
Figure 28: Successful Firmware Upgrade ................................................................................................. 29
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GNSS Module Series
1 Introduction
This document provides info on the steps needed to evaluate the Quectel L76 series modules using the
Evaluation Board (EVB). The EVB is a reference tool that allows you to become familiar with the L76 series
modules.
Specifically, the document is divided into several sections:
⚫
⚫
⚫
⚫
⚫
⚫
Chapter 2 provides the general overview of EVB Kit accessories.
Chapter 3 describes the EVB user interfaces.
Chapter 4 describes how to communicate with a module by using the QCOM tool;
Chapter 5 describes how to test the module by using the QGNSS tool;
Chapter 6 describes how to upgrade firmware of the module by using the QGPSFlashTool;
Chapter 7 is an appendix, which summarizes the relevant documents, terms and abbreviations
appearing herein.
In this document, Quectel L76 series includes L76, L76-L and L76-LB modules. For the EVB user guide of
L76-L (L) and L76-LB (L) modules, see document [4].
⚫
NOTE
If you need EVB schematic and PCB layout design files for reference, request them from Quectel Technical
Supports (support@quectel.com).
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GNSS Module Series
2 General Overview
2.1. EVB Kit Accessories
The EVB Kit includes Evaluation Board (EVB), Active GNSS Antenna, Micro-USB Cable, Bolts and
Coupling Nuts. You can download the software tools (QCOM, QGNSS, QGPSFlashTool) from our website
Download Zone or request them from Quectel Technical Supports.
The EVB Kit accessories are shown in the figure below, and check Table 1 for details.
Active GNSS antenna
Bolts and coupling nuts
EVB
Micro-USB cable
Figure 1: EVB Kit Accessories
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Table 1: List of Accessories
Items
Description
Quantity
EVB
Evaluation Board
Size: 60 mm × 70 mm
1
USB Cable
Micro-USB Cable
1
GNSS Antenna
Active GNSS Antenna
Request the Antenna Datasheet from Quectel Technical
Supports.
1
Instruction Sheet
A sheet that lists instructions: how to connect the EVB,
details on EVB accessories, and much more.
1
Other
Bolts and Coupling Nuts
4 pairs
2.2. Connecting Cables and Antenna to EVB
The connection between the EVB and its accessories is shown in the figure below. For detailed information
on how to connect the EVB and its accessories, refer to the instruction sheet inside the EVB Kit.
Figure 2: EVB and Accessories Assembly
NOTE
Place the active GNSS antenna where it can detect the satellites with a clear view of the sky.
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3 Board User Interfaces
3.1. EVB Top View
EVB top view is shown in the figure below.
J101
U101
Antenna connector L76 series module
J106
Test points
S101
STANDBY switch
D101
1PPS and TXD
indication LEDS
J301
UART connector
J201
Micro-USB connector
UART
S201
Power switch
S301
USB swicth
Z101
RESET button
Z102
FORCE_ON button
EVB version
Figure 3: EVB Top View
3.2. Board User Interfaces
The EVB interfaces are detailed in the table below.
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Table 2: Detailed EVB Interfaces
Function
Interfaces
Description
Power Supply
J201
Micro-USB
Power supply input:
⚫ DC power supply: 4.5–5.5 V, typ. 5.0 V
⚫ Current capability should be > 100 mA
J201
Micro-USB
NMEA sentence output and command input
J301
UART
NMEA sentence output and command input
J101
Antenna Connector
The antenna in the kit supports:
⚫ GPS L1 C/A
⚫ GLONASS L1
⚫ BeiDou B1I
⚫ QZSS L1 C/A
⚫ SBAS L1
User Interface
RF Input
Signal Indication
Switches and Buttons
Test Points
D101
Indication LEDS
TXD
(Blue LED)
Flash: Data output from UART TXD.
Extinct or Bright: No data output from UART
TXD.
1PPS
(Red LED)
Flash: Successful position fix.
The frequency is 1 Hz.
Extinct: No position fix.
S201
Power Switch
Power the EVB on/off
S101
STANDBY Switch
(ENTER↔EXIT)
Switch to “ENTER”, the module enters the
standby mode.
Switch to “EXIT”, the module exits the
standby mode.
S301
UART↔USB Switch
Switch between USB data transfer and
UART data transfer features.
Z101
RESET Button
Short press the button to reset the module.
Z102
FORCE_ON Button
Short press the button to wake up the
module from the backup mode.
J106
Test Points
Pins are detailed in Table 3 below.
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GNSS Module Series
Test point distribution is shown below:
J106 Pin Assignment:
32K/DRIN
AADET_N
1PPS
STANDBY
GND
TIMER
RESET
TXD1
RXD1
GND
Table 3: J106 Pin Detailed Description
Pin Name
I/O
Description
32K/DRIN
-
NC
AADET_N
-
NC
1PPS
DO
1 pulse per second
STANDBY
DI
Enters or exits the standby mode
GND
-
Ground
TIMER
DO
An open drain output signal which controls the ON/OFF status
of GNSS modules
RESET
DI
Resets the module
TXD
DO
Transmits data
RXD
DI
Receives the data
GND
-
Ground
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4 Using QCOM Tool to Communicate
This chapter illustrates how to use the QCOM tool to communicate with the module via the Micro-USB
interface.
Download the QCOM tool from our website Download Zone.
4.1. Communication via the Micro-USB Interface
Step 1: Connect the EVB and the PC with a Micro-USB cable via the Micro-USB interface.
Step 2: Set the power switch (S201) to ON position to power on the EVB and switch S301 to USB position.
Step 3: Run the provided driver installer to install the USB driver.
Step 4: View the USB port numbers in the Device Manager, as shown in the figure below.
Figure 4: USB Port
Step 5: Install the QCOM tool provided by Quectel. The COM Port Setting interface of QCOM is shown
in the figure below.
Figure 5: COM Port Setting Interface of QCOM
Step 6: Select the correct “COM Port” (USB Port shown in Figure 4 above).
Step 7: Set the correct “Baudrate” (default value: 9600 bps).
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Step 8: Click “Open Port” as shown in Figure 5 above, then the communication with EVB is established
successfully. In this case, the NMEA sentences output by the module will be displayed through
the QCOM tool, as shown in Figure 6 below. For more information about QCOM usage, see
document [1].
Figure 6: NMEA Sentences Output by Module – Displayed on QCOM Tool Interface
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5 Using QGNSS Tool to Test
This chapter provides a brief explanation on the QGNSS software tool which can be used to verify the
status of GNSS modules. For more information about QGNSS usage, see document [2].
Download the QGNSS tool from our website Download Zone.
5.1. COM Port and Baud Rate Setting
Step 1: Assemble the EVB Accessories.
Step 2: Set the power switch (S201) to ON position in order to power on the EVB and switch S301 to
USB position.
Step 3: Start the QGNSS and click “Setting” and “Serial Port Configuration” (the L76 series supports
9600 bps by default), as shown in the figure below.
Figure 7: QGNSS Setting
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Step 4: Click the “Connect or disconnect” button. After connecting the module, the interface as
shown in the figure below.
Figure 8: QGNSS Interface (Connected)
5.1.1. Interface Explanation
You can view GNSS information, such as CNR info, time, position, speed, and precision in the QGNSS
interface. To find out more about these parameters, see the following table.
Table 4: Explanation of QGNSS Interface
Icon
Explanation
This sky view interface shows the satellite position of the satellites
in use. The left column icons show the satellites in use and their
numbers.
⚫ BDS (BeiDou): 4
⚫ GLO (GLONASS): 0
⚫ GPS: 11
⚫ GAL (Galileo): 0
⚫ QZSS: 0
⚫ NavIC: 0
⚫ SBAS: 0
The grid map on the right shows the position of the satellites in
use.
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GPS satellite
BeiDou satellite
GLONASS satellite
Galileo satellite
QZSS satellite
NavIC satellite
⚫
⚫
⚫
⚫
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PRN 30 CNR is 39 dB/Hz.
Column in bright red means that the navigation data of the
satellite is in use.
PRN 1 CNR is 21 dB/Hz.
Column in light red means that the navigation data of this
satellite is not in use.
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
Longitude (unit: degree)
Latitude (unit: degree)
Altitude (MSL) (unit: m)
Altitude (EPH) (unit: m)
Receiver speed (unit: km/h)
Horizontal dilution of precision
Position dilution of precision
Fix Mode
UTC date and time
Total duration (unit: second)
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
Last TTFF (unit: second)
Quality Indicator
Total Times
Fixed Points
RTK Float
RTK Fixed
CEP 95 (unit: m)
RMS (unit: m)
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5.2. TTFF Testing
The QGNSS tool allows you to execute TTFF (Time to First Fix) testing under the following testing
conditions:
⚫
⚫
⚫
⚫
Full cold start
Cold start
Warm start
Hot start
QGNSS configuration steps for TTFF testing:
Step 1: Click the “Tools” menu, and select the “Static TTFF Testing” as shown in the figure below.
Figure 9: Static TTFF Testing via QGNSS
Step 2: Select “Restart type”, set the “Number of tests” and “TTFF Time-out (Sec)”, as shown in the
figure below.
Figure 10: TTFF Test Settings
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Step 3: AGNSS is optional when testing TTFF with QGNSS 1, as shown in the figure below. Click “Set
AGNSS” button to set up online AGNSS. For more information, see Chapter 5.3.1.
Figure 11: AGNSS Setting
Step 4: Click on the “Run” button to start the test. OR
Click on the “Stop” button to stop the test.
Figure 12: Run or Stop Test
1
You can set AGNSS either in this step, or before the TTFF setting through the ways illustrated in Chapter 5.3.
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Step 5: View the test results displayed visually in charts as shown in the figure below. The test results
are stored in the directory where the tool is installed.
Figure 13: Test Results
5.3. AGNSS Setting
There are two ways to use AGNSS to improve the TTFF.
5.3.1. Assistant GNSS Online
Step 1: Click the “AGNSS” menu, and select the “Assistant GNSS Online” as shown in the figure below.
Figure 14: AGNSS Setting via QGNSS – Assistant GNSS Online
Step 2: In the “Assistant GNSS Online” interface, fill in the FTP server information, and set “Time”,
“Position” and “Restart type” according to your needs.
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GNSS Module Series
Figure 15: Assistant GNSS Online Setting
Step 3: After clicking the “Connect” button, select online AGNSS files according to your needs and then
click “Download selected file” to download the files from the server.
Figure 16: Connect and Download – AGNSS Online
Step 4: Click the “Select file” button to select the files to be downloaded to the module, and then click
the “Reset and Transfer” button to start downloading, as shown in the figure below.
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Figure 17: Download Selected File – AGNSS Online
Step 5: When the download is successful, the progress bar will indicate 100 % and there will be a green
rectangle on the screen, as shown in the figure below.
Figure 18: Successfully Downloaded to the Module – AGNSS Online
5.3.2. Assistant GNSS Offline
Step 1: Click the “AGNSS” menu, and select the “Assistant GNSS Offline” as shown in the figure below.
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Figure 19: AGNSS Setting via QGNSS - Assistant GNSS Offline
Step 2: In the “Assistant GNSS Offline” interface, fill in the FTP server information, and set “Time”,
“Position” and “Restart type” according to your needs.
Figure 20: Assistant GNSS Offline Setting
Step 3: After clicking the “Connect” button, select the offline AGNSS files according to your needs and
then click “Download selected file” to download the files from the server.
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Figure 21: Connect and Download – AGNSS Offline
Step 4: Click the “Select file” button to select the files to be downloaded to the module, and then click
the “Download to module” button to start downloading, as shown in the figure below.
Figure 22: Download Selected File – AGNSS Offline
Step 5: When the download is successful, the progress bar will indicate 100 % and there will be a green
rectangle on the screen, as shown in the figure below.
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Figure 23: Successfully Downloaded to the Module – AGNSS Offline
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6 Using QGPSFlashTool to Upgrade
Firmware
Quectel L76 series module supports firmware upgrade via UART interface by using the QGPSFlashTool.
Download the QGPSFlashTool from our website Download Zone.
Before you start the firmware upgrade process:
First: Connect the EVB to a PC using a Micro-USB cable.
Second: Set the power switch (S201) to ON position to power on the EVB and switch S301 to USB.
Firmware upgrade steps:
Step 1: Open QGPSFlashTool. Click “Config”, then select “Options” as shown in the figure below.
Figure 24: Firmware Upgrade – Step 1
Step 2: In the Options popup, set the number of channels to be used. In the “Tool Options” drop-down
list, select “L76” 2, then click “OK” as shown in the figure below.
2
Select “L76” for all L76 series modules including L76, L76-L and L76-LB.
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Figure 25: Firmware Upgrade – Step 2
Step 3: Double click the “ROM file” field to select the ROM file, e.g. “L76LBNR03A01SCV03_GLN.bin”,
then
double
click
the
“DA
File”
field
to
select
the
DA
file,
e.g.
“MTK_AllInOne_DA_MT3333_MP.bin”, as shown in the figure below.
Figure 26: Firmware Upgrade – Step 3
Step 4: Confirm the “Serial Port” and “Baudrate”, and then then click “Start” to download, as shown in
the figure below.
The setting of the baud rate will affect the download speed. Based on Step 2, the baud rate will
be automatically selected.
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Figure 27: Firmware Upgrade – Step 4
Step 5: When the firmware upgrade is successful, the progress bar will indicate 100 % and there will be
a green rectangle on the screen, as shown in the figure below.
Figure 28: Successful Firmware Upgrade
⚫ NOTE
Make sure the module is in continuous mode before firmware upgrading.
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7 Appendix References
Table 5: Related Documents
Document Name
[1] Quectel_QCOM_User_Guide
[2] Quectel_QGNSS_User_Guide
[3] Quectel_QGPSFlashTool_User_Guide
[4] Quectel_L76-L(L)&L76-LB(L)_EVB_User_Guide
Table 6: Terms and Abbreviations
Abbreviation
Description
2D
2 Dimension
3D
3 Dimension
BeiDou
BeiDou Navigation Satellite System
COM Port
Communication Port
CEP
Circular Error Probable
CNR
Carrier-to-Noise Ratio
DI
Digital Input
DO
Digital Output
EPH
Ellipsoidal Height
ESD
Electrostatic Discharge
EVB
Evaluation Board
GND
Ground
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GNSS
Global Navigation Satellite System
GPS
Global Positioning System
I/O
Input/Output
LED
Light Emitting Diode
LNA
Low-Noise Amplifier
Micro-USB
Micro Universal Serial Bus
MSL
Mean Sea Level
NMEA
NMEA (National Marine Electronics Association) 0183 Interface Standard
PC
Personal Computer
PI
Power Input
PMTK
MTK Proprietary Protocol
PO
Power Output
PPS
Pulse Per Second
PRN
Pseudorandom Noise
RMS
Root Mean Square
RTK
Real-Time Kinematic
RXD
Receive Data (Pin)
SBAS
Satellite-Based Augmentation System
SPS
Standard Positioning Service
SV
Satellite Vehicle
TTFF
Time to First Fix
TXD
Transmit Data (Pin)
USB
Universal Serial Bus
UTC
Coordinated Universal Time
WGS84
World Geodetic System 1984
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