27
Document MT1600P.2019.A
© Xsens Technologies B.V.
MTi Family Reference Manual
5
Input and Output Specification
In this chapter the various output modes of the MTi are described. The MTi
’s have
several output
options. It is possible to select a different output frequency and/or output format (e.g. float or double)
per output or group of outputs. A full overview of the output options can be found in the
MT Low Level
Communication Protocol Documentation
13
.
Performance specifications on orientation, position and sensor data can be found in the specific
datasheets of each MTi series.
5.1 Overview of data output protocols
The MTi supports different data protocols: the binary (hexadecimal) XBus protocol, NMEA (ASCII)
messages and CAN 2.0. Refer to
MT Low Level Communication Protocol Documentation
CAN Protocol Documentation to learn more about the structure of the protocols and how to switch
between them.
NOTE: The MTi 1-series only supports the binary XBus protocol.
5.2 Overview of data inputs
The MTi-670 requires GNSS receiver data to provide a full GNSS/INS solution. This can be achieved
by using the UBX protocol (uBlox proprietary protocol) or with NMEA input.
When connecting a uBlox receiver (e.g. uBlox MAX-M8), the MTi will configure it correctly on start-up.
No prior configuration of the uBlox receiver is required.
Alternatively, NMEA input (NMEAin) is a functionality that allows the input of data from an external GNSS
receiver using the NMEA protocol. As almost all GNSS receivers support the output of NMEA messages,
this functionality enables the use of virtually any GNSS receiver.
It is important to note that when using the NMEAin both the GNSS receiver and the MTi must be
configured prior to connecting both systems to each other. The NMEAin for the MTi-670 can be enabled
through an Xbus message called SetGnssReceiverSettings, described in the
MT Low Level
Communication Protocol Documentation
8
. For the GNSS receiver settings, please review the
MTi 600-
series Datasheet
The MTi-7 does not support NMEAin, please contact your sales representative for more information.
5.3 Built-in self-test
All MTi
’s feature a built
-in self-test (BIT). The self-test actuates the mechanical structures in the MEMS
accelerometer and gyroscope by inducing an electric signal. This allows checking the proper functioning
of the mechanical structures in the MEMS inertial sensors as well as the signal processing circuitry. For
the magnetometer, the self-test checks the integrity of the sensor component.
A passed self-test will result in a valid self-test flag in the status byte. Because the self-test influences
the sensor data, the self-test is only available in Config mode. For more information, look for
RunSelftest
in
MT Low Level Communication Protocol Documentation.
5.4 Timestamp and packet counter output
Each data message can be accompanied by a packet counter and/or timestamp. Refer to
MT Low Level
Communication Protocol Documentation
detailed information on the various time outputs.
13
Links to the latest available documentation can be found via the following link:
