Xsens » Code » MTi-1_example

Example of using Xbus library to communicate with an MTi-1 series device using a full-duplex UART connection.

Important Information

This example is deprecated and no longer maintained. There are new embedded examples available in the MT SDK folder of the MT Software Suite. For more information please visit: https://xsenstechnologies.force.com/knowledgebase/s/article/Introduction-to-the-MT-SDK-programming-examples-for-MTi-devices

Overview

The example program demonstrates connecting to an MTi-1 series device, restoring communications settings to default if necessary, and configuring the MTi to send data. For an MTi-1 the device is configured to send inertial sensor data, while MTi-2 and MTi-3 devices are configured to output orientation data using the onboard XKF3i filter.

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.

For more information on the MTi-1 series communication protocol please refer to the datasheet: https://www.xsens.com/download/pdf/documentation/mti-1/mti-1-series_datasheet.pdf

Supported Platforms

The program has been tested on the following mbed platforms:

Using the Example

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.
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 (P300-5)
- 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 ADD1 (P300-19)
  - MT_ADD2 to ADD2 (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)

For more information on the MTi-1 development board please refer to the MTi-1 series user manual: https://www.xsens.com/download/pdf/documentation/mti-1/mti-1-series_dk_user_manual.pdf

Information

Check the defines at the top of main.cpp to determine which IO pins are used for the MT_xxx connections on each mbed platform.

Information

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.

Connect to the target using a serial terminal. The application is configured for:
- Baudrate = 921600
- Stop bits = 1
- No parity bits
- No flow control
Reset the mbed board.
You should be presented with a simple user interface as shown below:

MTi-1 series embedded example firmware.
Device ready for operation.
Found device with ID: 03880011.
Device is an MTi-3: Attitude Heading Reference System.
Output configuration set to:
        Packet counter: 65535 Hz
        Sample time fine: 65535 Hz
        Quaternion: 100 Hz
        Status word: 65535 Hz

Press 'm' to start measuring and 'c' to return to config mode.

main.cpp@4:98f063b2e6da, 2015-05-13 (annotated)

Committer:: Alex Young
Date:: Wed May 13 12:02:31 2015 +0200
Revision:: 4:98f063b2e6da
Parent:: 2:b3e402dc11ca
Child:: 5:abc52dd88be2

Use Xbus parser to handle data from MT.

Who changed what in which revision?

User	Revision	Line number	New contents of line
Alex Young	4:98f063b2e6da	1	#include "mbed.h"
Alex Young	4:98f063b2e6da	2	#include "xbusparser.h"
Alex Young	4:98f063b2e6da	3
Alex Young	4:98f063b2e6da	4	static Serial pc(PA_2, PA_3);
Alex Young	4:98f063b2e6da	5	static Serial mt(PB_9, PB_8);
Alex Young	4:98f063b2e6da	6	static XbusParser* xbusParser;
Alex Young	4:98f063b2e6da	7	static uint8_t rxBuffer[256];
Alex Young	4:98f063b2e6da	8
Alex Young	4:98f063b2e6da	9	static void* allocateBuffer(size_t bufSize)
Alex Young	4:98f063b2e6da	10	{
Alex Young	4:98f063b2e6da	11	return bufSize < sizeof(rxBuffer) ? rxBuffer : NULL;
Alex Young	4:98f063b2e6da	12	}
Alex Young	4:98f063b2e6da	13
Alex Young	4:98f063b2e6da	14	static void mtLowLevelHandler(void)
Alex Young	4:98f063b2e6da	15	{
Alex Young	4:98f063b2e6da	16	while (mt.readable())
Alex Young	4:98f063b2e6da	17	{
Alex Young	4:98f063b2e6da	18	XbusParser_parseByte(xbusParser, mt.getc());
Alex Young	4:98f063b2e6da	19	}
Alex Young	4:98f063b2e6da	20	}
Alex Young	4:98f063b2e6da	21
Alex Young	4:98f063b2e6da	22	static void mtDataHandler(uint8_t mid, uint16_t dataLength, uint8_t const* data)
Alex Young	4:98f063b2e6da	23	{
Alex Young	4:98f063b2e6da	24	pc.printf("Received Xbus message. MID=%X, length=%d\n", mid, dataLength);
Alex Young	4:98f063b2e6da	25	}
Alex Young	4:98f063b2e6da	26
Alex Young	4:98f063b2e6da	27
Alex Young	4:98f063b2e6da	28	static void configureSerialPorts(void)
Alex Young	4:98f063b2e6da	29	{
Alex Young	4:98f063b2e6da	30	pc.baud(921600);
Alex Young	4:98f063b2e6da	31	pc.format(8, Serial::None, 2);
Alex Young	4:98f063b2e6da	32
Alex Young	4:98f063b2e6da	33	mt.baud(921600);
Alex Young	4:98f063b2e6da	34	mt.format(8, Serial::None, 2);
Alex Young	4:98f063b2e6da	35	mt.attach(mtLowLevelHandler, Serial::RxIrq);
Alex Young	4:98f063b2e6da	36	}
Alex Young	4:98f063b2e6da	37
Alex Young	2:b3e402dc11ca	38	int main(void)
Alex Young	2:b3e402dc11ca	39	{
Alex Young	4:98f063b2e6da	40	XbusParserCallback xbusCallback = {};
Alex Young	4:98f063b2e6da	41	xbusCallback.allocateBuffer = allocateBuffer;
Alex Young	4:98f063b2e6da	42	xbusCallback.handleMessage = mtDataHandler;
Alex Young	4:98f063b2e6da	43
Alex Young	4:98f063b2e6da	44	xbusParser = XbusParser_create(&xbusCallback);
Alex Young	4:98f063b2e6da	45	configureSerialPorts();
Alex Young	4:98f063b2e6da	46	}