Example for updating the MTi-1's firmware. Uses a platform independent, retargetable pure C implementation of the firmware updater protocol.

Dependencies:   mbed-rtos mbed


The purpose of this example is to demonstrate how to update the firmware of an MTi-1 series module using the FwUpdate library. The FwUpdate library is provided as C source in the xbus directory. It is setup to be platform independent and easily retargetable. The user must provide an instance of the FwUpdate struct having the platform specific callback function filled in. Refer to fwupdate.h for more information.

The example embeds an Xsens Firmware File (XFF). The XFF used is the official 1.1.1 MTi1-series firmware release. If needed binary copies of specific firmware files can be requested through our support department. We used srecord to convert the XFF to the C data array (See xffdata.c and xffdata.h). When using requested Xsens provided XFF file use srecord as follows:

srec_cat firmware.xff -binary -o xffdata.c -C-array g_xffData -include

This example updates the firmware only. The eMTS (extended Motion Tracker Settings) are not updated. This means that in rare cases (e.g. when hardware filter parameters are updated), you do not take full advantage of the filter update. Most functionality, such as filter behavior, outputs, output formats and communication options are updated with this example. Please use the Windows/Linux FW updater when HW parameters are updated (see release notes to check if HW parameters were changed).

Communication with the MTi-1 series device is implemented using a either a full-duplex UART, I2C or SPI bus. A reset line is used to reset the MTi during initialization. Data is output to a host PC terminal using a second UART.

Supported Platforms

The program has been tested on the following mbed platforms:

Porting to other mbed platforms is relatively be easy by adding its specific port information to board.h. It is however necessary that the board has sufficient code flash/ROM to keep a copy of the XFF (150K). In case you store the XFF data in a different memory (e.g. an external memory) you must re-implement the readXffData callback function.

Using the Example

  1. To use the example program connect one of the supported mbed boards to the host PC and download the application from the mbed online compiler to the target device.
  2. With the mbed board unpowered (USB disconnected) wire the mbed board to the MTi-1 development board. The following connections are required:
    • In all cases:
      • 5V (or 3V3) main supply to VDD (P300-1)
      • MCU IO voltage (IORef) to VDDIO (P300-2)
      • GND to GND (P300-3)
      • MT_NRESET to nRST P(300-5)
    • For I2C communication:
      • MT_SCL to I2C_SCL (P300-9)
      • MT_SDA to I2C_SDA (P300-11)
      • MT_DRDY to DRDY (P300-15)
      • MT_ADD0 to ADD0 (P300-17)
      • MT_ADD1 to ADD0 (P300-19)
      • MT_ADD2 to ADD0 (P300-21)
    • For SPI communication:
      • MT_DRDY to DRDY (P300-15)
      • MT_SCLK to SPI_SCK (P300-17)
      • MT_MISO to SPI_MISO (P300-19)
      • MT_MOSI to SPI_MOSI (P300-21)
      • MT_nCS to SPI_nCS (P300-23)
    • For UART communication:
      • MT_RX to UART_TX (P300-9)
      • MT_TX to UART_RX (P300-11)


Check the defines in board.h to determine which IO pins are used for the MT_xxx connections on each mbed platform.


The active peripheral (I2C, SPI or UART) is selected on the MTi-1 development board through the PSEL0 and PSEL1 switches. Look on the bottom of the development board for the correct settings.

  1. Connect to the target using a serial terminal. The application is configured for:
    • Baudrate = 921600
    • Stop bits = 1
    • No parity bits
    • No flow control
  2. Reset the mbed board.
  3. You should be presented with a simple user interface as shown below:
Embedded firmware updater example
Interface: I2C

h: Print this text
c: GotoConfig
m: GotoMeasurement
r: Soft reset the module
b: GotoBootloader
v: Request firmware revision
d: Request deviceId
u: Start firmware update (make sure module is in bootloader mode)
x: Hard reset the module and make it stay in bootloader 

To do a firmware update

  • Make the MTi-1 enter bootloader mode. Either through 'b' or 'x'
  • You can check if the MTi-1 is in bootloader by requesting the firmware revision ('v'). The bootloader revision always starts with 255
  • Press 'u' to start the firmware update
  • After about 20 seconds the "Firmware update ready" message should appear indicating the update succeeded
  • The device should automatically reboot into its application firmware (use 'v' to verify)

Revision graph

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