Ublox EVK-M101 User manual


EVK-M101, EVK-M101C
Evaluation kit
User guide
Abstract
This document describes the structure and use of the EVK-M101
and the EVK-M101C evaluation kits and provides information for
evaluating u-blox M10 positioning technology.
www.u-blox.com
UBX-21003949 - R04
C1-Public

EVK-M101, EVK-M101C-User guide
Document information
Title EVK-M101, EVK-M101C
Subtitle Evaluation kit
Document type User guide
Document number UBX-21003949
Revision and date R04 23-Sep-2022
Disclosure restriction C1-Public
This document applies to the following products:
Product name Type number FW version IN/PCN reference
EVK-M101 EVK-M101-00-01 SPG 5.10 UBX-22013432
EVK-M101C EVK-M101C-00-01 SPG 5.10 UBX-22024090
u-blox or third parties may hold intellectual property rights in the products, names, logos and designs included in this
document. Copying, reproduction, or modification of this document or any part thereof is only permitted with the express
written permission of u-blox. Disclosure to third parties is permitted for clearly public documents only.
The information contained herein is provided "as is" and u-blox assumes no liability for its use. No warranty, either express
or implied, is given, including but not limited to, with respect to the accuracy, correctness, reliability and fitness for a
particular purpose of the information. This document may be revised by u-blox at any time without notice. For the most recent
documents, visit www.u-blox.com.
Copyright © 2022, u-blox AG.
UBX-21003949 - R04

Page 2 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
Contents
1 Product description.............................................................................................................. 5
1.1 Overview.................................................................................................................................................... 5
1.2 Kit contents..............................................................................................................................................5
1.3 System requirements.............................................................................................................................5
2 Specifications......................................................................................................................... 6
2.1 Safety precautions..................................................................................................................................6
2.2 Approvals...................................................................................................................................................6
3 Getting started...................................................................................................................... 7
3.1 u-center 2 installation............................................................................................................................7
3.2 Hardware installation............................................................................................................................. 7
3.3 Interface default configuration............................................................................................................ 7
4 Device description.................................................................................................................8
4.1 Interface connection...............................................................................................................................8
4.1.1 Interface switch.............................................................................................................................. 8
4.1.2 14-pin connector............................................................................................................................ 9
4.1.3 USB..................................................................................................................................................10
4.1.4 UART...............................................................................................................................................10
4.1.5 SPI....................................................................................................................................................11
4.1.6 I2C....................................................................................................................................................11
4.2 GNSS input signal................................................................................................................................ 11
4.2.1 Antenna connector...................................................................................................................... 11
4.3 Time pulse.............................................................................................................................................. 12
4.4 Reset button..........................................................................................................................................12
4.5 Safe boot button...................................................................................................................................12
4.6 LED...........................................................................................................................................................12
4.7 Flash memory........................................................................................................................................ 12
4.8 Super capacitor.....................................................................................................................................12
4.9 External interrupt................................................................................................................................. 13
5 Current measurement....................................................................................................... 14
5.1 GNSS current.........................................................................................................................................14
5.2 Backup current...................................................................................................................................... 14
6 Block diagram.......................................................................................................................15
7 Board layout..........................................................................................................................16
8 Device configuration.......................................................................................................... 17
8.1 Communication ports.......................................................................................................................... 17
8.1.1 UART baud rate configuration.................................................................................................. 19
8.2 GNSS configuration..............................................................................................................................20
8.3 Navigation update rate........................................................................................................................20
8.4 Internal LNA mode configuration......................................................................................................21
8.5 Power modes..........................................................................................................................................22
8.5.1 Backup modes.............................................................................................................................. 23
UBX-21003949 - R04

Contents Page 3 of 30
C1-Public

9 Troubleshooting...................................................................................................................24
10 Common evaluation pitfalls.......................................................................................... 26
Related documents................................................................................................................ 27
Revision history.......................................................................................................................28
Appendix.................................................................................................................................... 29
A Glossary......................................................................................................................................................29

EVK-M101, EVK-M101C-User guide
1 Product description
1.1 Overview
The EVK-M101 and the EVK-M101C evaluation kits make evaluating the high performance and low
power consumption of u-blox M10 positioning technology simple (see an overview of u-blox M10
features on www.u-blox.com/m10).
The built-in USB interface provides both power supply and USB-to-Serial communication to the
receiver, keeping the possibility to also connect through a 14-pin connector or a dedicated RS-233
port. The versatile interfaces and measurement points enable advanced evaluation needs.
u-blox evaluation kits are compact, and their user-friendly interface and power supply make them
ideally suited for use in laboratories or vehicles. Furthermore, they can be used with a desktop or a
laptop, making them the perfect companion through all stages of design-in projects.
Evaluation kit Description Related products
EVK-M101 u-blox M10 evaluation kit with TCXO u-blox UBX-M10050-KB chips [1]
MAX-M10S module [2]
MIA-M10Q module [3]
EVK-M101C u-blox M10 evaluation kit with crystal u-blox UBX-M10050-KB chips [1]
MAX-M10M module
MIA-M10C module
Table 1: EVK-M101/C supported products
1.2 Kit contents
The delivered package contains:
• Compact 105 x 64 x 26 mm EVK-M101/C unit
• Active GNSS antenna with 3 m cable
• USB 2.0 cable (Type-C)
• EVK Welcome card
1.3 System requirements
• PC with USB interface (compatible with USB 2.0) or RS-232 interface
• Operating system: Microsoft Windows 8.1 onwards (x86 and x64 versions)
• Internet connection for the first-time use in order to download the required Windows drivers.
See section u-center 2 installation for details.
UBX-21003949 - R04

1 Product description Page 5 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
2 Specifications
Parameter Specification
Serial interfaces 1 USB 2.0 Type-C
1 UART, max baud rate 921600 baud
RS-232 +/- 5.0 V level
14 pin, 3.3 V logic
1 I2C, max 400 kHz
1 SPI, max SPI CLK 5.5 MHz
Timing interfaces 1 time pulse output
Dimensions 105 x 64 x 26 mm
Power supply 5.0 V via USB or powered via external power supply pin 14
(5V_IN) and pin 1 (GND)
Normal operating temperature -40 °C to +65 °C
Table 2: EVK-M101/C specifications
2.1 Safety precautions
EVK-M101/C must be supplied by a PS1 class limited power source. See section 6.2.2.4 of IEC
62368-1:2018 [4] for more information on the PS1 class.
In addition to a limited power source, only ES1 class circuits are to be connected to the EVK-M101/C,
including interfaces and antennas. See section 5.2.1.1 of IEC 62368-1:2018 [4] for more information
on the ES1 class.
2.2 Approvals
The EVK-M101/C is designed for the presumption of conformity with the essential requirements
and other relevant provisions of Radio Equipment Directive (RED) 2014/53/EU.
The EVK-M101/C complies with the Directive 2011/65/EU (EU RoHS 2) and its amendment Directive
(EU) 2015/863 (EU RoHS 3).
The Declaration of Conformity (DoC) is available at u-blox website within Support > Product
Resources > Conformity Declaration.
UBX-21003949 - R04

2 Specifications Page 6 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
3 Getting started
3.1 u-center 2 installation
u-center 2, the u-blox interactive evaluation software tool is required for configuration, testing,
visualization and data analysis of u-blox GNSS receivers as well as EVKs. The EVK user guide
together with the u-center 2 evaluation tool provide useful assistance during all phases of a system
integration project. To install the u-center 2 evaluation software tool, follow the steps available on
www.u-blox.com/product/u-center. For more information on how to use the u-center 2 evaluation
software tool, refer to the u-center 2 User guide [5].
The required Windows drivers for the FTDI FT4232H USB-to-UART converter that is used in the EVK
are available from the Microsoft Windows Update service. To ensure that the latest FTDI drivers
are installed automatically from Windows Update, check and uninstall the previously installed
FTDI drivers. The Windows system driver search mechanism will download and install the FTDI
drivers automatically from the Microsoft Windows Update service. If the automatic installation fails,
contact u-blox support to get the FTDI drivers and install manually.
3.2 Hardware installation
1. Connect the EVK-M101/C to a PC running Microsoft Windows. The available interfaces are
listed below. Refer to section Device description for more information on the interfaces.
•USB-C: Connect via USB-C port that is connected internally to an FTDI USB-to-UART
converter. Set interface switch to UART (option 0) or I2C/UART (option 2).
•UART: Connect via RS-232 or through the 14-pin connector. Set interface switch to UART
(option 0) or I2C/UART (option 2).
•SPI, I2C: Connect via corresponding pins on the 14-pin connector. Set interface switch
accordingly to SPI (option 1) or I2C/UART (option 2). Refer to Figure 2 to see these
interface positions.
Use UART (option 0) if the internal SPI flash memory is in use.
Press the RST button after changing the switch setting.
2. The device must always have power, either via USB on the back panel or through the 5V_IN
input on the front panel of the EVK.
3. Connect the provided GNSS antenna to the evaluation unit and place the antenna in a
location with clear sky view.
4. Start the u-center 2 evaluation tool and select corresponding COM port and baud rate.
3.3 Interface default configuration
Parameter Description Remark
UART, Input UBX and NMEA protocol at 38400 baud
UART, Output UBX and NMEA protocol at 38400 baud Only NMEA messages are activated by default
SPI / I2C, Input UBX and NMEA protocol
SPI / I2C, Output UBX and NMEA protocol Only NMEA messages are activated by default
Table 3: Default configuration
The SPI, I2C and UART interfaces on the 14-pin connector are available for debugging and
design-in purposes.
UBX-21003949 - R04

3 Getting started Page 7 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
4 Device description
EVK-M101/C evaluation kit contains u-blox M10 GNSS receiver, RTC, SPI flash memory, DC-DC
converter, LNA, SAW filter, and external TCXO or crystal depending on the EVK variant. In addition,
the EVK includes I2C current sensors that provide an option for current measurements through the
on-board FTDI USB-to-I2C interface as shown in Figure 4.
4.1 Interface connection
The EVK-M101/C supports UART, I2C and SPI communication interfaces. For connecting the EVK
to a PC, use a standard SUBD-9 cable or the included USB Type-C cable depending on the interface
in use. The EVK also includes an on-board USB-to-Serial converter for USB-to-UART communication
with the receiver. For current measurements and to evaluate the available digital interfaces,
additional measurement equipment and devices can be connected to the 14-pin connector on the
front panel of the EVK unit.
Do not drive any of the IO pins when the EVK is not supplied.
Figure 1: Connecting the EVK-M101/C unit for power supply and communication
Figure 2 shows the front and the back panel of the EVK-M101/C evaluation unit.
Figure 2: EVK-M101/C front and back panels
4.1.1 Interface switch
Use the interface switch on the front panel to choose between I2C/UART, SPI communication with
the receiver and using the internal SPI flash memory. You must reset the EVK unit by pressing the
RST button after the interface switch setting is changed.
The interface switch setting should only be changed after the EVK unit is powered off,
otherwise changing the slide switch position while the EVK is still powered on could damage
the GNSS receiver chip.
UBX-21003949 - R04

4 Device description Page 8 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
1. UART (option 0) – In this selection, the EVK communicates with the receiver through the
UART interface and allows the use of the internal SPI flash memory.
2. SPI (option 1) – In this selection, the EVK communicates with the receiver only through the
SPI interface. RS-232 is switched off.
3. I2C / UART (option 2) – In this selection, communication via 3.3 V I2C interface is available
and the EVK can also communicate with the receiver through the UART interface (via USB or
RS-232 – back panel or the 3.3 V level TXD/MISO, RXD/MOSI pins at the front panel).
4.1.2 14-pin connector
The EVK-M101/C front panel has a 14-pin connector that provides PIO, communication interfaces
and supply options. All these pins are ESD protected. The 14-pin connector can be used for
communicating with the receiver through UART, SPI, and I2C interfaces. In addition, the 14-pin
connector provides flexibility for evaluating other advanced scenarios.
Pin no. Pin name I/O Level Description
14 5V_IN I 4.75 - 5.25 V Power input – can be used instead of USB.
13 GNSS I2 O 3.3 V Supply current measurement (total current) node 2. See pin
12 description.
12 GNSS I1 O 3.3 V Supply current measurement (total current) node 1. Current
measured from voltage over a 0.1 Ω 1% resistor between
pins 12 (GNSS I1) and 13 (GNSS I2). Pin 12 (GNSS I1) is
at higher potential. NOTE: the total current includes the
V_CORE, V_RF, and V_IO current consumption 1.
11 BCKP I1 O 3.3 V Backup supply current measurement node 1. Connected to
backup supply (super capacitor). Current measured from
voltage over a 100 Ω 1% resistor between pins 11 (BCKP I1)
and 10 (BCKP I2). Pin 11 (BCKP I1) is at higher potential.
10 BCKP I2 O 3.3 V Backup supply current measurement node 2. See pin 11
description.
9 VBCKP I 3.3 V Backup power supply input – optional input for testing
backup operation.
8 TIMEPULSE O 3.3 V Time pulse signal (50 ohms output). Can also be used as
generic input/output (PIO4). The time pulse signal can be re-
assigned as LNA_EN signal for controlling the external LNA.
In this configuration, the LNA_EN jumper on the EVK board
should be left open (i.e. not connected).
7 EXTINT I 3.3 V External interrupt signal. Can be used for time mark feature,
time aiding, and wakeup from power save modes.
6 LNA_EN I/O 3.3 V LNA enable signal that controls the external LNA.
When this pin is used as an input, the LNA_EN jumper on the
EVK board should be left open (i.e. not connected).
When this pin is used as an output, the LNA_EN jumper on the
EVK board can be open or connected.
5 SDA/CS I/O 3.3 V If the interface switch slide is on I2C (option 2), then the I2C
interface is selected; Function: data input / output.
If the interface switch slide is on SPI (option 1), then the
SPI interface is selected; Function: chip select input (ACTIVE
LOW).
4 SCL/SCK I 3.3 V Clock input for I2C and SPI interfaces.
3 TxD/MISO O 3.3 V Serial port transmit or SPI slave transmit, operation selected
by interface switch.
1V_IO is connected to 3.3 V supply. V_CORE and V_RF power domains are connected to 1.0 V. See section GNSS current
for more details.
UBX-21003949 - R04

4 Device description Page 9 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
Pin no. Pin name I/O Level Description
2 RxD/MOSI I 3.3 V Serial port receive or SPI slave receive, operation selected by
interface switch.
1 GND I – Recommended common ground pin.
Table 4: EVK-M101/C 14-pin connector pin description
Figure 3: EVK-M101/C 5.0 V DC power supply example
When using the 3.3 V digital interfaces with your application (e.g. SPI or I2C), a cable length
less than 25 cm is recommended.
4.1.3 USB
The USB Type-C connector in the evaluation kit can be used for both power supply and
communication. The easiest way to evaluate the EVK-M101/C operation is to connect the EVK
to a PC with the USB-C 2.0 cable and then to use the u-center 2 tool to configure and monitor
the GNSS functions. The USB connector is internally connected to a USB-to-Serial converter that
connects to the UART interface of the u-blox M10 receiver, which allows the USB connector to be
used for communication as well. Interface switch (option 0) and (option 2) can be used for USB
communication with the receiver.
When the EVK is connected to the PC, Windows creates a virtual COM port to the PC. This newly
created virtual COM port needs to be selected in the u-center 2 evaluation tool for communicating
with the receiver. EVK-M101/C supports USB-to-UART communication speeds up to 921600 baud.
4.1.4 UART
The EVK unit includes two options for the UART connection, one is an RS-232 port for serial
communication with the PC and the other one is through the 14-pin connector. By default, the UART
communication speed is set to 38400 baud and EVK-M101/C supports speeds up to 921600 baud.
The following Interface switch options are available for UART communication:
•Option 0: when the internal SPI flash memory is used.
•Option 2: when the internal SPI flash memory is not used.
4.1.4.1 RS-232
Connect to the RS-232 port on the PC using a straight RS-232 serial cable with male and female
connectors. The maximum cable length is < 3.0 meters. To configure the RS-232 port, use the UBX-
CFG-VALSET command and select CFG-UART1 Configuration group in the u-center 2 evaluation
tool. The maximum operating baud rate is 921600 baud. Note, if a USB-to-RS-232 adapter cable
is used, it can be connected directly to the RS-232 port of the evaluation kit. The RS-232 port also
UBX-21003949 - R04

4 Device description Page 10 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
provides TIMEPULSE output signal and supports evaluation of EXTINT functions such as time mark,
time aiding, and wakeup from power save modes.
The 9-pin RS-232 female connector is assigned as listed below:
Pin no. Assignment
1 & 6 Time pulse
2 TXD/SPI_MISO (GNSS Transmit Data, serial data to external device)
3 RXD/SPI_MOSI (GNSS Receive Data, serial data from external device)
4 EXTINT
5 GND
7, 8 & 9 not connected
Table 5: EVK-M101/C RS-232 connector pin description
4.1.4.2 UART through 14-pin connector
The EVK also provides UART communication through the 14-pin connector on pins TxD and RxD,
see section 14-pin connector for more information.
4.1.5 SPI
The SPI interface pins are available on the 14-pin connector, see section 14-pin connector for more
information.
If the SPI interface is used for communication with the receiver, the Interface switch must
be set to SPI (option 1).
4.1.6 I2C
The 14-pin connector contains pins for evaluating I2C bus communication. If the I2C interface is
used, the Interface switch must be set to I2C (option 2).
By default, the optional I2C pull-up resistors are not populated on the EVK board. The u-blox M10
GNSS receiver already contains internal pull-up resistors for normal use. If fast communication
speed with long cable length is needed, the optional pull-up resistors can be placed to the reserved
location on the EVK board.
4.2 GNSS input signal
To evaluate the GNSS reception, the GNSS signal must be supplied to the antenna input SMA
connector of the evaluation kit. EVK-M101/C evaluation kit includes a GPS / Galileo / GLONASS /
BeiDou antenna with a 3.0 m cable. It is possible to connect various active and passive GNSS
antennas with SMA connectors or provide a signal from a recorded or simulated GNSS RF source
to the antenna input. Also, an external SAW filter can be connected to the RF input connector, for
evaluating an SAW-LNA-SAW improved immunity performance.
4.2.1 Antenna connector
For connecting an active or a passive antenna, an SMA female connector is available on the front
panel of the EVK unit (see Figure 2). The RF path on EVK-M101/C contains an LNA and an SAW filter
having 3.3 V DC voltage in the RF input. The EVK provides 3.3 V bias supply for the external antenna
and the recommended maximum antenna supply current for active antennas is 30 mA. This pin is
also ESD protected.
Avoid having a short at the RF input because there is no short circuit detection or antenna
supervisor feature on the EVK-M101/C.
UBX-21003949 - R04

4 Device description Page 11 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
4.3 Time pulse
u-blox receivers include a time pulse function that provides pulses with a configurable pulse period,
pulse length and polarity (rising or falling edge). The u-center 2 evaluation tool can be used to
configure the time pulse parameters. The time pulse signal is available at the 14-pin and RS-232
connectors. In addition, the time pulse signal is inverted and connected to the LED on the front panel
of the EVK.
The time pulse signal from the 14-pin connector has 50 ohms output and thus, no fast
slope output signal is possible.
4.4 Reset button
The RST button on the front panel resets the u-blox M10 receiver.
4.5 Safe boot button
This button is used to set the receiver into safeboot mode. In this mode, the receiver executes only
the minimal functionality.
The safeboot mode is not recommended in EVK-M101/C because the u-blox M10 receiver is
using a ROM-based firmware and thus, it is not necessary to go into safe boot mode.
4.6 LED
On the front panel of the EVK unit, a single blue LED shows the time pulse signal as well as the status
that the device is supplied. The LED starts flashing one pulse per second during a GNSS fix. If there
is no GNSS fix, the LED will only be lit, without flashing.
4.7 Flash memory
EVK-M101/C has a 16-Mbit SPI flash that is connected to the u-blox M10 receiver. By default it can
be used to:
• Store the current configuration permanently.
• Save data logging results.
•Hold AssistNow™ Offline and AssistNow™ Autonomous data.
Only the UART interface (option 0) is available for communication with the receiver when
the flash is in use. See section Interface switch for more information.
A token is required to be able to download AssistNow™ Offline. Refer to the u-center 2 User
guide [5] for more information.
4.8 Super capacitor
The evaluation kit board includes a 1.0 F super capacitor to supply the backup power domain of the
EVK-M101/C and is charged whenever there is a power supply available, either via USB or through
the 14-pin connector. The super capacitor provides backup power directly to the EVK-M101/C
V_BCKP power input of the GNSS receiver in case no other V_BCKP power supply is provided. The
super capacitor allows more than 12 hours of backup power, when it is fully charged to 3.3 V.
Avoid doing a hot start before having applied the power supply (from USB or from the 14-
pin connector) for few minutes because the super capacitor requires about 200 seconds to
charge to 2.0 V and about 1000 seconds to charge fully to 3.3 V.
UBX-21003949 - R04

4 Device description Page 12 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
The V_BCKP power supply can be used to provide power for any desired period of time while
evaluating for very long backup periods.
4.9 External interrupt
On the EVK-M101/C, the external interrupt (EXTINT) signal is available on the 14-pin connector and
on the RS-232 port. The EXTINT signal can be used for time mark and time aiding features of the
receiver, as well as for waking up the receiver from power save modes. See sections 14-pin connector
and RS-232 for more information.
UBX-21003949 - R04

4 Device description Page 13 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
5 Current measurement
5.1 GNSS current
At startup, the receiver starts in acquisition mode to search for available satellites and to download
GNSS orbital data, i.e., ephemeris and almanac. Once the data has been downloaded, the receiver
enters tracking mode. In continuous operation, the receiver typically remains in tracking mode once
entering it. The current consumption reduces when the receiver enters the tracking mode. The time
required to enter tracking mode can be reduced by downloading aiding data from the AssistNow™
Online service.
On EVK-M101/C, the main supply voltage for the u-blox M10 GNSS receiver is 3.3 V. The EVK
contains an internal 3.3 V to 1.0 V DC-DC converter to reduce power consumption from the V_CORE
and V_RF power domains of the receiver. To measure the total GNSS supply current with EVK-M101/
C, follow these steps:
1. Power up EVK-M101/C.
2. Connect a true RMS voltmeter across GNSS I1 (pin 12) and GNSS I2 (pin 13) of the 14-pin
connector.
3. Read the voltage (and average if necessary) on the voltmeter and convert to current (1 mV
equals 10 mA).
4. Perform the test with good signals and clear sky view to ensure that the receiver can acquire
the satellite signals.
The total GNSS current (IVCC) shows the current consumption from the V_CORE, V_RF, and V_IO
power domains. The IV_IO current includes the contribution from the TCXO current consumption of
around 1.5 mA.
The DC-DC has an average efficiency of 85 %, resulting in a higher power consumption than
the values defined in the M10050-KB data sheet.
The separate current contribution from IV_IO and IV_CORE + V_RF can be measured from
available test points on the EVK board that are connected to the I2C current sensors on the
EVK as shown in Figure 4.
5.2 Backup current
To measure the backup current (IBCKP) with EVK-M101/C, follow these steps:
1. Connect a true RMS voltmeter across BCKP I1 (pin 11) and BCKP I2 (pin 10) of the 14-pin
connector.
2. Remove power supply (USB cable or other external power supply from the 14-pin connector).
3. Read the voltage (and average if necessary) on the voltmeter and convert to current (1 mV
equals 10 µA).
UBX-21003949 - R04

5 Current measurement Page 14 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
6 Block diagram
EVK-M101/C block diagram providing an overview on supply voltages, current measurement and
communication interfaces is shown in Figure 4.
Figure 4: EVK-M101/C block diagram
UBX-21003949 - R04

6 Block diagram Page 15 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
7 Board layout
Figure 5: EVK-M101/C board layout
Figure 6: EVK-M101/C PCB
UBX-21003949 - R04

7 Board layout Page 16 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
8 Device configuration
This section shows how to configure and evaluate some important receiver features on EVK-M101/
C related to power modes, GNSS constellations, navigation rate, and internal LNA modes of the
receiver. In addition, the receiver can be configured with the Advanced Configuration View of the u-
center 2 evaluation tool as shown in Figure 7.
Figure 7: EVK-M101/C receiver configuration view
The receiver configuration can be saved to the receiver RAM, or to the battery-backed RAM
(BBR), or to the available SPI flash memory. The RAM content is cleared after the power supply is
disconnected or in software standby mode and the off state of On/Off power save mode (PSMOO).
Therefore, it is recommended to save the receiver configuration to RAM and BBR or permanently in
Flash. The BBR content is maintained as long as the backup battery supply is available. The content
of the flash memory is preserved between power cycles and thus, it is the preferred option for long-
term storage of the receiver configuration.
8.1 Communication ports
The FTDI USB-to-UART converter generates four virtual communication (COM) ports as shown in
Figure 8. The third COM port based on the COM port ID is the correct port to use. For example, if the
generated COM ports are COM1, COM2, COM3, and COM4, then the port to use is COM3.
If the RS-232 port is also connected to the same PC, there will be an additional COM port for
the RS-232 serial connection.
UBX-21003949 - R04

8 Device configuration Page 17 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
Figure 8: EVK-M101/C communication ports
The identification of EVK-M101/C on Windows machines has been improved to provide descriptive
names to each virtual communication (COM) port as shown in Figure 9.
•EVK-M101 current sensors: Do not use this COM port.
•EVK-M101 I2C: Do not use this COM port.
•EVK-M101 UART: Use this COM port for UART communication with the receiver via the FTDI
USB-to-UART interface.
•EVK-M101 port D: Do not use this COM port.
The COM ports may appear differently on old Windows compared to current Windows
version.
UBX-21003949 - R04

8 Device configuration Page 18 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
Figure 9: EVK-M101/C communication ports identification on Windows
8.1.1 UART baud rate configuration
The baud rate for the UART communication to the receiver can be configured in the CFG-UART1-
BAUDRATE configuration key or in the CFG-UART2-BAUDRATE configuration key depending on the
UART interface that is in use. The default baud rate is set to 38400 as shown in Figure 10, and the
maximum baud rate is 921600.
UBX-21003949 - R04

8 Device configuration Page 19 of 30
C1-Public

EVK-M101, EVK-M101C-User guide
Figure 10: EVK-M101/C UART baud rate configuration
Setting a different baud rate will interrupt communication. If other configuration keys
were set after, these will not be applied. Therefore, the new baud rate needs to be selected
manually to resume communication and apply the remaining configuration items.
8.2 GNSS configuration
The default GNSS constellations that are enabled on the receiver are GPS, Galileo, SBAS and
QZSS. The receiver GNSS configuration can be updated by selecting the constellations in the GNSS
Configuration View as shown in Figure 11.
Figure 11: EVK-M101/C receiver GNSS configuration
8.3 Navigation update rate
The CFG-RATE-MEAS configuration key that is shown in Figure 12 can be used to configure
the navigation update rate. The navigation update rate value is defined in ms, where 100 ms
corresponds to 10 Hz. The default update rate is 1000 ms which corresponds to 1 Hz. The default
1 Hz update rate is a good tradeoff between position accuracy and power consumption. Certain
applications require faster update rates for high performance but this will increase the receiver
power consumption.
UBX-21003949 - R04

8 Device configuration Page 20 of 30
C1-Public