Ublox EVK-M8T-0-01 User manual

EVK-M8T
Evaluation Kit
User Guide

Abstract
This document describes the structure and use of the EVK-
M8T evaluation kit and provides
information for evaluating and testing u-
blox M8 positioning technology for timing and raw data
applications.
www.u-blox.com
UBX-14041540 - R05

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Document Information
Title EVK-M8T
Subtitle User Guide
Document type User Guide
Document number UBX-14041540
Revision and date R05 20-May-2018
Document status Early Production Information
This document applies to the following products:
Product name Type number Hardware version ROM/FLASH version PCN reference
EVK-M8T EVK-M8T-0-01 B Flash FW 3.01 TIM 1.10 UBX-16005636
European Union regulatory compliance
EVK-M8T complies with all relevant requirements for RED 2014/53/EU. The EVK-M8T Declaration of Conformity (DoC) is
available at www.u-blox.com under Support --> Product Resources --> Conformity Declaration.
u-blox or third parties may hold intellectual property rights in the products, names, logos and designs included in this
document. Copying, reproduction, modification or disclosure to
third parties of this document or any part thereof is only
permitted with the express written permission of u
-blox.
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 ww
w.u-blox.com.
Copyright © u
-blox AG.

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Contents
Document Information................................................................................................................................2
Contents ..........................................................................................................................................................3
1Product description ..............................................................................................................................4
1.1 Overview........................................................................................................................................................ 4
1.2 Kit includes ................................................................................................................................................... 4
1.3 Software and documentation................................................................................................................... 4
1.3.1 u-center GNSS evaluation software ............................................................................................... 4
1.4 System requirements ................................................................................................................................ 4
2Specifications ......................................................................................................................................... 5
2.1 Safety precautions ..................................................................................................................................... 5
3Getting Started......................................................................................................................................6
3.1 Software installation.................................................................................................................................. 6
3.2 Hardware installation................................................................................................................................. 6
3.3 Serial port default configuration ............................................................................................................. 6
4Device description................................................................................................................................. 7
4.1 Interface connection and measurement................................................................................................ 7
4.2 Active antenna............................................................................................................................................. 7
4.3 Evaluation unit............................................................................................................................................. 7
4.3.1 Antenna connector............................................................................................................................. 7
4.3.2 USB ........................................................................................................................................................ 7
4.3.3 UART ..................................................................................................................................................... 8
4.3.4 RST button...........................................................................................................................................8
4.3.5 Safe boot button.................................................................................................................................8
4.3.6 Slide Switch..........................................................................................................................................8
4.3.7 Test Connector.................................................................................................................................... 9
4.3.8 LED....................................................................................................................................................... 10
4.3.9 Backup Battery.................................................................................................................................. 10
4.3.10 GNSS Configuration......................................................................................................................... 10
5Measuring tracking current .............................................................................................................. 11
6Testing Power Save Mode ................................................................................................................ 12
7Block diagram ....................................................................................................................................... 13
8Board layout........................................................................................................................................... 14
9Schematic .............................................................................................................................................. 17
10 Battery replacement .......................................................................................................................... 18
11 Troubleshooting................................................................................................................................... 19
12 Common evaluation pitfalls ............................................................................................................. 21
Related documents ....................................................................................................................................22
Revision history...........................................................................................................................................22
Contact.......................................................................................................................................................... 23

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1Product description
1.1 Overview
EVK-M8T evaluation kit makes evaluating the high performance u-blox M8T positioning products
simple. The built-in USB interface provides both power supply and high-speed data transfer, and
eliminates the need for an external power supply. The u-blox evaluation kits are compact, and their
user friendly interface and power supply make them ideally suited for use in laboratories, vehicles
and outdoor locations. Furthermore, they can be used with a PDA or a notebook PC, making them the
perfect companion through all stages of design-in projects.
Evaluation Kit Description Suitable for
EVK-M8T u-blox M8 Timing GNSS Evaluation Kit NEO-M8T, LEA-M8T
Table 1: List of products supported by EVK-M8T evaluation kit
1.2 Kit includes
•Evaluation unit
•USB cable
•Active GPS / GLONASS / BeiDou antenna with 3 m cable
•Quick Start card
1.3 Software and documentation
The EVK installation software (and documentation) package can be downloaded from the Web; see
the Quick Start card for the URL.
1.3.1 u-center GNSS evaluation software
The installation software includes u-center, an interactive tool for configuration, testing,
visualization and data analysis of GNSS receivers. It provides useful assistance during all phases of
a system integration project.
1.4 System requirements
•PC with USB interface
•Operating system: Windows Vista onwards (x86 and x64 versions)
•USB drivers are provided in the evaluation kit installation software

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2Specifications
Parameter Specification
Serial Interfaces 1 USB V2.0
1 RS232, max. baud rate 921,6 kBd
DB9 +/- 12 V level
14 pin – 3.3 V logic
1 DDC (I2C compatible) max. 400 kHz
1 SPI – clock signal max. 5,5 MHz – SPI DATA max. 1 Mbit/s
Timing Interfaces 2 Time-pulse outputs
1 Time-mark input
Dimensions 105 x 64 x 26 mm
Power Supply 5V via USB or external powered via extra power supply
pin 14 (V5_IN) 13 (GND)
Normal Operating temperature -40°C to +65°C
Table 2: EVK-M8T specifications
2.1 Safety precautions
EVK-M8T must be supplied by an external limited power source in compliance with clause 2.5 of the
standard IEC 60950-1. In addition to an external limited power source, only separated or Safety Extra-
Low Voltage (SELV) circuits are to be connected to the evaluation kit, including interfaces and
antennas.
For more information about SELV circuits see section 2.2 in Safety standard IEC 60950-1 .
Warnings and certifications
CAUTION! IN THE UNLIKELY EVENT OF A FAILURE IN THE INTERNAL
PROTECTION CIRCUITRY THERE IS A RISK OF AN EXPLOSION WHEN CHARGING
FULLY OR PARTIALLY DISCHARGED BATTERIES. REPLACE THE BATTERY IF IT
NO LONGER HAS SUFFICIENT CHARGE FOR UNIT OPERATION. CONTROL THE
BATTERY BEFORE USING IF THE DEVICE HAS NOT BEEN OPERATED FOR AN
EXTENDED PERIOD OF TIME.
Products marked with this lead-free symbol on the product label comply with the
“
Directive 2002/95/EC of the European Parliament and the Council on the
Restriction of Use of certain Hazardous Substances in Electrical and Electronic
Equipment” (RoHS).
EVK-M8T evaluation kit is RoHS compliant and green (no halogens).

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3Getting Started
3.1 Software installation
☞Installation of the EVK-M8T software and documentation requires Internet access.
Choose Software only or Software and documentation installation package from u-blox website.
Once the zip file is downloaded and unzipped, unzip the file in Tools folder and double-click the
extracted exe file.
The software components will be installed on your system and placed under the “u-blox” folder in the
“Start Programs” menu.
3.2 Hardware installation
1. Connect the unit to a PC running Microsoft Windows. Options:
•USB: Connect via USB port.
•UART: Connect via RS232. Set slide switch to I2C.
•SPI / I2C compliant DDC: Connect corresponding pins (see Table 5 for pin description). Set slide
switch accordingly to SPI or I2C.
☞Press the RST button after changing the switch.
2. The device must always have power, either via USB on the back or the V5_IN input on the front.
3. Connect the GNSS antenna to the evaluation unit and place the antenna in a location with good
sky view.
4. Start the u-center GNSS Evaluation Software and select corresponding COM port and baud rate.
☞Refer to the u-center User Guide [5] for more information.
3.3 Serial port default configuration
Parameter Description Remark
UART Port 1, Input UBX and NMEA protocol at 9’600 Bd
UART Port 1, Output UBX and NMEA protocol at 9’600 Bd Only NMEA messages are activated
USB, Input UBX and NMEA protocol
USB, Output UBX and NMEA protocol Only NMEA messages are activated
Table 3: Default configuration

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4Device description
4.1 Interface connection and measurement
For connecting the EVK to a PC, use a standard SUBD-9 cable and the included Micro-USB cable.
Additional measurement equipment can be connected to the front connector.
Figure 1: Connecting the unit for power supply and communication
4.2 Active antenna
EVK-M8 evaluation kits include a GPS / GLONASS / BeiDou antenna with a 3 m cable. It is possible to
connect various active and passive GNSS antennas with SMA connectors to the evaluation unit.
The recommended maximum antenna supply current for active antennas is 30 mA.
4.3 Evaluation unit
Figure 2 shows the front and the rear panel of the EVK-M8T evaluation unit.
Front panel Rear panel
Figure 2: EVK-M8T evaluation unit – front and rear panels
4.3.1 Antenna connector
An SMA female jack is available on the front side (see Figure 2) of the evaluation unit for connecting
an active or passive antenna. DC voltage at the RF input is 3.3 V. The internal short circuit protection
limits the maximum current to 60 mA. Please note that the 30 mA maximum supply current for
active antenna stays the same. This pin is also ESD protected.
The u-blox NEO-M8T module used in the EVK-M8T incorporates an additional, off-chip LNA.
⚠The connector is only to be used with a GNSS antenna or simulator. Do not connect this
equipment to cable distribution systems.
4.3.2 USB
A USB V2.0 compatible serial port is featured for data communication and power supply.

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4.3.3 UART
The evaluation unit includes an RS232 port for serial communication that is compatible with PC
serial ports.
Connect using a straight RS232 serial cable with male and female connectors to the port on your
PC. The maximum cable length is < 3.0 meters. To configure the RS232 port, use the CFG-PRT
command in the u-center application. The maximum operating baud rate is 921.6 kBd.
If you are using a USB to RS232 adaptor cable, you can connect it directly to the evaluation kit RS232
port.
The 9-pin D-SUB female connector is assigned as listed in Table 4:
Pin Nr. Assignment
1 Time-pulse 1 output (RS-232 levels)
2 TXD, GNSS Transmit Data, serial data to DTE
3 RXD, GNSS Receive Data, serial data from DTE
4 Optional time-mark input (RS-232 levels) using EXTINT0 (internal jumper J6 fitment required)
5 GND
6 Time-pulse 1 output (RS-232 levels)
7 Not connected
8, 9 not connected
Table 4: SUB-D9 Connector pin description for EVK-M8T
4.3.4 RST button
The RST button on the front panel resets the unit. To avoid an inadvertent reset, the button is
recessed.
4.3.5 Safe boot button
This is used to set the unit in safe boot mode. In this mode the receiver executes only the minimal
functionality, such as updating new firmware into the SQI flash. In order to set the receiver in safe
boot mode please follow these steps.
1. Press the BOOT button and keep holding
2. Press the RST button
3. Release the RST button
4. Release the BOOT button
5. If the UART interface has to be used, the training sequence has to be sent to the receiver.
The training sequence is a transmission of 0x55 55 at the baud rate of 9600 Bd. Wait for at least
100 milliseconds before the interface is ready to accept commands.
4.3.6 Slide Switch
Use the slide switch on the front panel to choose between I2C (and UART) and SPI communication
ports. You must reset the unit by pressing the RST button when the slide switch has been changed.
1.
I2C – In this selection the EVK operates with the UART (RS232 DB9 – rear panel or the 3.3 V level
TxD (MISO), RxD (MOSI) at the front panel). Also the communication via 3.3 V DDC interface (I2C)
is selected.
2.
SPI – In this selection the EVK operates only with the SPI interface. RS232 (DB9) is switched off.

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4.3.7 Test Connector
This 14-pin test-connector provides additional functionality to the EVK, allowing access to the
interface pins and an ability to measure the current used by the EVK. All pins are ESD protected.
For accurate measurements, it is recommended to use a cable of at most 1 meter in length. Figure 3
shows an example of a power supply connected to the test connector by using standard adapter
cables from the manufacture Hirschmann. Figure 4 shows an example for overall current
measurement. When connecting the 3.3 V digital interfaces RS232, SPI and DDC to your application,
a cable length less than 25 cm is recommended.
PIN Nr. PIN NAME I/O LEVEL DESCRIPTION
14 V5_IN I 4.75 V - 5.25 V Power input – can be used instead of USB
13 GND I - Common ground pin
12 P1A (VCC) O 3.3 V Power output – max. current supply 100 mA
1Ω1% resistor for over-all current measurement to pin 11 (P1B)
NOTE: the current includes also SQI Flash, LNA
11 P1B O Second connection for over-all current measurement (see Figure 5)
10 P2A O 3.0 V Battery output (unloaded)
100 Ω1% resistor for battery backup current measurement to pin 9 (P2B)
NOTE: There is a current protection to 3 mA. See circuit in figure 7 (D2, D4,
R29)
9 P2B O Second junction for battery backup current measurement
8 TIMEPULSE 1 O 3.3V Time pulse 1 (internally buffered output)
7 EXTINT0 I 3.3 V External interrupt or time-mark input
6 TIMEPULSE 2 O 3.3 V Time pulse 2 (internally buffered output)
5 SDA / CS I/O 3.3 V If slide switch on I2C, then DDC interface selected; Function: data input /
output
If slide switch on SPI, then SPI interface selected; chip select input – LOW
ACTIVE
4 SCL / SCK I/O 3.3 V Clock input / output
3 TxD / MISO I/O 3.3 V If slide switch on I2C, then DDC interface selected / UART TxD (3.3V Level)
If slide switch on SPI, then SPI interface selected; Master in Slave out (MISO)
2 RxD / MOSI I/O 3.3 V If slide switch on I2C, then DDC interface selected / UART RxD (3.3V Level)
If slide switch on SPI, then SPI interface selected; Master out Slave in (MOSI)
1 GND I - Common ground pin
Table 5: Connector pin description for EVK-M8T (pins numbered from right to left on the front panel)
V5_IN
GND
GND
V5_IN
Hirschmann
Part Nr.: 934160100
Figure
3: Example 5V DC power supply

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4.3.8 LED
On the front panel of the unit, a single blue LED shows the time pulse 1 signal. The LED starts flashing
one pulse per second during a GNSS fix. If there is no GNSS fit, the LED will only light, without
flashing.
4.3.9 Backup Battery
There is a backup battery in the evaluation unit. This is necessary to store orbital information
between operations and to enable faster start-up. It is a RENATA 3.0 V Li / MnO²battery of the type
CR2450. The battery has a rated capacity of 540 mA. The battery operating temperature range is -
40° C to +85° C.
If the built-in backup battery runs low or is empty after a long storage period, purchase the battery
described above for replacement (refer to the section 10 for battery replacement guidelines).
⚠CAUTION! RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE. DISPOSE
OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS!
4.3.10 GNSS Configuration
The EVK-M8T supports GPS, QZSS, Galileo, GLONASS, and BeiDou.
The GNSS to be used can be configured on u-center (View Messages View then UBX-CFG-GNSS).
For more information, refer to the
u-center User Guide [5], the u-blox 8 / u-blox M8 Receiver
Description including Protocol Specification
[4].