Stand-alone multiradio modules with wi-fi & bluetooth, odin-w2 series (33 pages)
Summary of Contents for u-blox ZED-F9T
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ZED-F9T u-blox F9 high accuracy timing module Integration Manual Abstract This document describes the features and application of ZED-F9T, a multi- band GNSS module offering nanosecond level timing accuracy. www.u-blox.com UBX-19005590 - R01...
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The information contained herein is provided "as is" and u-blox assumes no liability for the use of the information. No warranty, either express or implied, is given with respect to, including but not limited to, the accuracy, correctness, reliability and fitness...
ZED-F9T - Integration Manual 1 Integration manual structure This document provides a wealth of information to enable a successful design with the ZED-F9T module. The manual is structured according to system, software and hardware aspects. The first section, "System description" outlines the basics of the ZED-F9T timing receiver.
22 x 17 mm. 2.1.1 Differential timing The u-blox ZED-F9T high accuracy timing receiver takes local timing accuracy to the next level with its differential timing mode. In differential timing mode correction data is exchanged with other neighboring ZED-F9T timing receivers via a communication network.
ZED-F9T - Integration Manual 2.2.1 Block diagram Figure 1: ZED-F9T block diagram An active antenna is mandatory with the ZED-F9T. UBX-19005590 - R01 2 System description Page 8 of 80 Advance Information...
RAM holds the current configuration, which is used by the receiver at run-time. It is constructed on start-up of the receiver from several sources of configuration. The configuration interface and the available keys are described fully in the ZED-F9T Interface Description [2].
Refer to the u-blox ZED-F9T Interface Description [2] for information about further settings. By default the ZED-F9T outputs NMEA 4.10 messages that include satellite data for all GNSS bands being received. This results in a higher-than-before NMEA load output for each navigation period.
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ZED-F9T only supports certain combinations of constellations and bands. For all constellations, both L1 and L2 bands must either be enabled or disabled. BeiDou B2 is the exception (can either have BeiDou B1+B2 or B1-only).
Table 5: Antenna power status 3.1.5 Differential timing mode configuration In differential timing mode the ZED-F9T can operate either as a master reference station or as a slave station. Using the RTCM3 protocol, the master sends timing corrections to the slave via a communication link enabling the slave to compute its time relative to the master with high accuracy.
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RTCM 1127 BeiDou MSM7 RTCM 1230 GLONASS code-phase biases RTCM 4072 Additional reference station information Table 6: ZED-F9T supported input RTCM version 3.3 messages 3.1.5.3 List of supported RTCM output messages Message Description RTCM 1005 Stationary RTK reference station ARP...
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3.1.5.5 Master reference station When the ZED-F9T high accuracy timing receiver acts as a master timing station, it sends RTCM 3.3 differential corrections to slave receivers. Corrections are generated after a timing fix calculation in order to remove the master receiver's clock offset.
Table 10: Configuration items used for setting a master reference station 3.1.5.6 Slave station When the ZED-F9T acts as a slave receiver, it receives differential corrections RTCM 3.3 messages from a master reference station and aligns its time pulse to it.
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ZED-F9T - Integration Manual 3.1.7.1 Platform settings u-blox receivers support different dynamic platform models (see table below) to adjust the navigation engine to the expected application environment. These platform settings can be changed dynamically without performing a power cycle or reset. The settings improve the receiver's interpretation of the measurements and thus provide a more accurate position output.
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fix has been achieved, which are further subdivided into specific types of fixes (e.g. 2D, 3D, dead reckoning). The ZED-F9T firmware does not support the dead reckoning position fix type. Where a fix has been achieved, a check is made to determine whether the fix should be classified as valid or not.
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ZED-F9T - Integration Manual position at very low speed. The output of the low-speed course over ground filter is published in the UBX-NAV-PVT message ( headMot field), UBX-NAV-VELNED message ( heading field), NMEA-RMC message ( cog field) and NMEA-VTG message ( cogt field). If the low-speed course over ground filter is not activated or inactive, then the course over ground is computed as described in section freezing the course over ground.
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ZED-F9T - Integration Manual Figure 3: Flowchart of the static hold mode 3.1.7.5 Freezing the course over ground If the low-speed course over ground filter is deactivated or inactive (see section low-speed course over ground filter), the receiver derives the course over ground from the GNSS velocity information.
SV. When a SV is lost after a successful 3D fix (min. four SVs available), the altitude is kept constant at the last known value. This is called a 2D fix. u-blox receivers do not calculate any navigation solution with less than three SVs. 3.2 Geofencing 3.2.1 Introduction...
LOW state can be configured using the CFG-GEOFENCE-PINPOL configuration item. 3.3 Interfaces ZED-F9T provides UART1, SPI, DDC (I C compatible) and USB interfaces for communication with a host CPU. The interfaces are configured via the configuration interface which is described in the ZED-F9T Interface Description [2].
3.3.2 SPI interface The ZED-F9T high accuracy timing receiver has an SPI slave interface that can be selected by setting D_SEL = 0. The SPI slave interface is shared with UART1. The SPI pins available are: SPI_MISO (TXD), SPI_MOSI (RXD), SPI_CS_N, SPI_CLK.
Table 14: D_SEL configuration 3.3.5 RESET_N interface The ZED-F9T high accuracy timing receiver provides the ability to reset the receiver. The RESET_N pin is an input-only pin with an internal pull-up resistor. Driving RESET_N low for at least 100 ms will trigger a cold start.
It is recommended to have the possibility to pull the SAFEBOOT_N pin low in the application. This can be provided using an externally connected test point or a host I/O port. 3.3.7 TIMEPULSE interface The ZED-F9T high accuracy timing receiver provides time pulse signals on the TIMEPULSE and TIMEPULSE 2 pins. 3.3.8 Display data channel (DDC)
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ZED-F9T - Integration Manual Figure 11: ZED-F9T antenna supervisor The bias-t inductor must be chosen for multi-band operation; a value of 120 nH 5% is required for our recommended Murata part if current is limited below its 110 mA rating. See antenna bias section for additional information.
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ZED-F9T - Integration Manual 3.3.9.2 Antenna short detection - ANT_SHORT_N Enable antenna short detection setting configuration item CFG-HW- ANT_CFG_SHORTDET to true (1). Result: • UBX-MON-RF in u-center: Antenna status = OK. Antenna power status = ON • ANT_OFF = active high to disable an external antenna therefore the pin is low to enable an external antenna.
ON/OFF control. Leave open if unused, this function is disabled by default. 3.3.11 Communication ports u-blox receivers are enabled with a highly flexible communication interface. It supports a variety of protocols, and is truly multi-port and multi-protocol capable. See Interface Description for the supported protocols.
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ZED-F9T - Integration Manual Port # Electrical interface DDC (I²C compatible) 0x0000 0x0001 UART1 0x0102 UART2 0x0003 0x0004 Table 16: Port number assignment reported in the UBX-MON-COMMS message. 3.3.11.1 UART ports The serial ports consist of an RX and a TX line. Neither handshaking signals nor hardware flow control signals are available.
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Figure 12: SPI back-to-back read/write access 3.3.11.3 USB port A single USB port is provided for host communication purposes. See the ZED-F9T Data sheet [1] for availability. This port can be used for communication purposes and to power the positioning chip or module.
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Unlike all other interfaces, the DDC is not able to communicate in full-duplex mode, i.e. TX and RX are mutually exclusive. u-blox receivers act as a slave in the communication setup, therefore they cannot initiate data transfers on their own. The host, which is always master, provides the data clock (SCL), and the clock frequency is therefore not configurable on the slave.
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ZED-F9T - Integration Manual 3.3.11.5.1.1 Read access forms There are two forms of DDC read transfer. The "random access" form includes a slave register address and thus allows any register to be read. The second "current address" form omits the register address. If this second form is used, then an address pointer in the receiver is used to determine which register to read.
Internet. Data supplied by the AssistNow Online Service can be directly uploaded to a u-blox receiver in order to substantially reduce time to first fix (TTFF), even under poor signal conditions. The system works by collecting data such as ephemeris and almanac from the satellites through u-blox's "Global Reference Network"...
• Enable and use flow control to prevent loss of data due to buffer overflow in the receiver. u-blox provides the source code for an example library, called libMGA, that provides all of the functionality we expect in most host software.
(trying to acquire new signals), it is possible that the internal buffers will overflow and some messages will be lost. In order to combat this, u-blox receivers support an optional flow control mechanism for assistance.
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For example, if the position is accurate to 100km or better, the u-blox receiver will choose to go for a more optimistic startup strategy. This will result in quicker startup time. The receiver will decide which strategy to choose, depending on the "pacc"...
In order to protect customers against the impact of such outages, u-blox runs at least two instances of the AssistNow Online Service on independent machines. Customers have a choice of requesting assistance data from any of these servers, as all will provide the same information.
Depending on the configuration of the receiver, such "invalid" times may well be output, but with flags indicating their state (e.g. the "valid" flags in UBX-NAV-PVT). u-blox receivers employ multiple GNSS system times and/or receiver local times (in order to support multiple GNSS systems concurrently), so users should not rely on UBX messages that report GNSS system time or receiver local time being supported in future.
ZED-F9T - Integration Manual Time reference Message GPS time UBX-NAV-TIMEGPS BeiDou time UBX-NAV-TIMEBDS GLONASS time UBX-NAV-TIMEGLO Galileo time UBX-NAV-TIMEGAL UTC time UBX-NAV-TIMEUTC Table 19: GNSS times 3.5.5 Time validity Information about the validity of the time solution is given in the following form: •...
Leap second information can be polled from the u-blox receiver with the message UBX-NAV-TIMELS. 3.5.8 Real time clock u-blox receivers contain circuitry to support a real time clock, which (if correctly fitted and powered) keeps time while the receiver is otherwise powered off. When the receiver powers up, it attempts to use the real time clock to initialize receiver local time and in most cases this leads to appreciably faster first fixes.
3.6.1 Time pulse 3.6.1.1 Introduction The ZED-F9T receiver includes two time pulse outputs with configurable duration and frequency. The time pulse function can be configured using the CFG-TP-* configuration group for the desired time pulse; TP1 or TP2. Note that TP1 refers to pin 53 (Timepulse) and TP2 to pin 54 (Timepulse 2).
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ZED-F9T - Integration Manual Figure 18: Timepulse 3.6.1.2 Recommendations • The time pulse can be aligned to a wide variety of GNSS times or to variants of UTC derived from them (see the chapter on time bases). However, it is strongly recommended that the...
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Although u-blox receivers can combine a variety of different GNSS times internally, the user must choose a single type of GNSS time and, separately, a single type of UTC for input (on EXTINTs) and output (via the Time Pulse) and the parameters reported in corresponding messages.
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ZED-F9T - Integration Manual It is possible to define different signal behavior (i.e. output frequency and pulse length) depending on whether or not the receiver is locked to a reliable time source. Time pulse signals can be configured using the configuration group CFG-TP-*.
ZED-F9T - Integration Manual Figure 21: Timemark 3.7 Security (operating, monitoring and maintaining) A host application should be designed to monitor the various security indicators and provide the information to the user. 3.7.1 Receiver status monitoring Messages in the UBX class UBX-MON are used to report the status of the parts of the embedded computer sub-system that are not GNSS specific.
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ZED-F9T - Integration Manual If the amount of data configured is too much for a certain port's bandwidth (e.g. all UBX messages output on a UART port with a baud rate of 9600), the buffer will fill up. Once the buffer space is exceeded, new messages to be sent will be dropped.
Also, the algorithms rely on availability of signals from multiple GNSS constellations; the detection does not work in single GNSS mode. 3.8 u-blox protocol feature descriptions 3.8.1 Broadcast navigation data This section describes the data reported via UBX-RXM-SFRBX.
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ZED-F9T - Integration Manual 3.8.1.2 GPS The data structure in the GPS L1C/A and L2C signals is dissimilar and thus the UBX-RXM-SFRBX message structure differs as well. For the GPS L1C/A and L2C signals it is as follows: 3.8.1.2.1 GPS L1C/A For GPS L1C/A signals, there is a fairly straightforward mapping between the reported subframe and the structure of subframe and words described in the GPS ICD.
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ZED-F9T - Integration Manual UBX-RXM-SFRBX message. Data bits 1 to 8 are always a hamming code, whilst bits 81 to 84 are a string number and bit 85 is the idle chip, which should always have a value of zero. The meaning of other bits vary with string and frame number.
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ZED-F9T - Integration Manual Note that as the BeiDou data words only comprise 30 bits, the 2 most significant bits in each word reported by UBX-RXM-SFRBX are padding and should be ignored. 3.8.1.5 Galileo The Galileo E1 C/B and E5 bl/bQ signals both transmit the I/NAV message but in different configurations.
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ZED-F9T - Integration Manual Figure 26: Galileo E1 C/B subframe words 3.8.1.5.2 Galileo E5 b1/bQ For Galileo E5 b1/bQ signals, each reported subframe contains a pair of I/NAV pages as described in the Galileo ICD. Galileo pages can either be "Nominal" or "Alert" pages. For Nominal pages the eight...
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ZED-F9T - Integration Manual Figure 27: Galileo E5 b1/bQ subframe words Alert pages are reported in very similar manner, but the page type bits will have value 1 and the structure of the eight words will be slightly different (as indicated by the Galileo ICD).
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ZED-F9T - Integration Manual • Hardware reset uses the on-chip watchdog, in order to electrically reset the chip. This is an immediate, asynchronous reset. No Stop events are generated. • Controlled software reset terminates all running processes in an orderly manner and, once the system is idle, restarts operation, reloads its configuration and starts to acquire and track...
The pin assignment of the ZED-F9T module is shown in Figure 28. The defined configuration of the PIOs is listed in Table The ZED-F9T is an LGA package with the I/O on the outside edge and central ground pads. Figure 28: ZED-F9T pin assignment Pin No Name Description...
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ZED-F9T - Integration Manual Pin No Name Description VCC_RF Voltage for external LNA Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Ground Reserved Reserved Ground Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved GEOFENCE_STAT Geofence status, user defined Reserved Reserved Reserved Reserved...
The VCC pin is connected to the main supply voltage. During operation, the current drawn by the module can vary by some orders of magnitude. For this reason, it is important that the supply circuitry be able to support the peak power for a short time (see the ZED-F9T Data sheet [1] for specification).
4.2.3 ZED-F9T power supply The ZED-F9T high accuracy timing receiver requires a low noise, low dropout voltage, very low source impedance power supply of 3.3V typically. No inductors or ferrite beads should be used from LDO to the module VCC pin.
ZED-F9T - Integration Manual Figure 30: Minimal ZED-F9T design For a minimal design with the ZED-F9T GNSS modules, the following functions and pins should be considered: • Connect the power supply to VCC and V_BCKP. • If hot or warm start operations are needed, connect a Backup Battery to V_BCKP.
ZED-F9T - Integration Manual Figure 31: u-blox low cost dual-band antenna internal structure A suitable ground plane is required for the antenna to achieve good performance. Location of the antenna is critical to reach the stated performance. L1 + L2/E5b active antenna required specifications Parameter Specification...
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ZED-F9T - Integration Manual antenna if the supply voltage of the ZED-F9T module matches the antenna working voltage (e.g. 3.0 V). A series current limiting resistor is required to prevent short circuits destroying the bias-t inductor. The bias-t inductor must be chosen for multi-band operation, a value of 120 nH 5% is recommended for the recommended Murata L part.
EOS/ESD/EMI handling and protection measures. To prevent overstress damage at the RF_IN of your receiver, never exceed the maximum input power as specified in the u-blox ZED-F9T Data sheet [1]. 4.5.1 ESD protection measures GNSS receivers are sensitive to Electrostatic Discharge (ESD). Special precautions are required when handling.
Figure 37: Active antenna EOS protection 4.5.3 Safety precautions The ZED-F9T must be supplied by an external limited power source in compliance with the clause 2.5 of the standard IEC 60950-1. In addition to external limited power source, only Separated or Safety Extra-Low Voltage (SELV) circuits are to be connected to the module including interfaces and antennas.
ZED-F9T - Integration Manual EMI protection measures are particularly useful when RF emitting devices are placed next to the GNSS receiver and/or to minimize the risk of EMI degradation due to self-jamming. An adequate layout with a robust grounding concept is essential in order to protect against EMI.
4.7.2 Package footprint and solder mask Refer to the ZED-F9T Data Sheet [1] for the mechanical dimensions. 4.7.3 Layout guidance Presented layout guidance reduces the risk of performance issues at design level with the ZED-F9T high accuracy timing receiver. 4.7.3.1 RF In trace The RF In trace has to work in the combined GNSS L1 + L2 signal band.
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4.7.3.2 Vias for the ground pads The ground pads under the ZED-F9T high accuracy timing receiver need to be grounded with vias to the lower ground layer of the PCB. A solid ground layer fill on the top layer of the PCB is recommended.
4.7.3.3 VCC pads The VCC pads for the ZED-F9T high accuracy timing receiver need to be as low an impedance as possible with large vias to the lower power layer of the PCB. The VCC pads need a large combined pad and the de-coupling capacitors must be placed as close as possible.
ZED-F9T - Integration Manual 4.8.3 RF front-end circuit options It is mandatory that the RF input is fed by an active antenna meeting the requirements for the ZED-F9T. The first stages of the signal processing chain are crucial to the overall receiver performance.
• Is the ZED-F9T placed away from any heat source? • Is the ZED-F9T placed away from any air cooling source? • Is the ZED-F9T shielded by a cover/case to prevent the effects of air currents and rapid environmental temperature changes? •...
5 Product handling 5.1 ESD handling precautions ZED-F9T high accuracy timing receivers contain highly sensitive electronic circuitry and are Electrostatic Sensitive Devices (ESD). Observe precautions for handling! Failure to observe these precautions can result in severe damage to the GNSS receiver! •...
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ZED-F9T - Integration Manual As a reference, see the “IPC-7530 Guidelines for temperature profiling for mass soldering (reflow and wave) processes”, published in 2001. Preheat phase During the initial heating of component leads and balls, residual humidity will be dried out. Note that this preheat phase will not replace prior baking procedures.
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ZED-F9T - Integration Manual Optical inspection After soldering the module, consider an optical inspection step. Cleaning No cleaning with water, solvent, ultrasonic cleaner should be carried out: • Cleaning with water will lead to capillary effects where water is absorbed in the gap between the baseboard and the module.
EMI covers is done at the customer’s own risk. The numerous ground pins should be sufficient to provide optimum immunity to interferences and noise. u-blox makes no warranty for damages to the module caused by soldering metal cables or any other forms of metal strips directly onto the EMI covers.
The ZED-F9T high accuracy timing receiver GNSS modules are deliverable in quantities of 250 pieces on a reel. The ZED-F9T high accuracy timing receiver receivers are shipped on Reel Type B, as specified in the u-blox Package Information Guide. See the u-blox Package Information Guide [3].
ZED-F9T - Integration Manual 8 Revision history Revision Date Name Status / Comments 15-Mar-2019 tkoi Advance Information Added a design-in restriction for ANT_DETECT pin in section Design. Mechanical specification figure updated in section Layout. UBX-19005590 - R01 8 Revision history Page 79 of 80 ...
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ZED-F9T - Integration Manual Contact For complete contact information visit us at www.u-blox.com. u-blox Offices North, Central and South America Headquarters Asia, Australia, Pacific Europe, Middle East, Africa u-blox America, Inc. u-blox AG u-blox Singapore Pte. Ltd. Phone: +1 703 483 3180...