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

Dependencies:   mbed-rtos mbed Xbus

Fork of MTi-1_example by Alex Young

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This example is deprecated and no longer maintained.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

  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 (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.

  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:
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.
Committer:
Alex Young
Date:
Thu May 21 16:45:07 2015 +0200
Revision:
48:69d35430fe8b
Parent:
28:ae74baf7e5ab
Child:
49:38ecfbff5391
Add documentation for xbusmessage

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Alex Young 18:2073072bad51 1 /*!
Alex Young 18:2073072bad51 2 * \file
Alex Young 18:2073072bad51 3 * \copyright
Alex Young 18:2073072bad51 4 * Copyright (C) Xsens Technologies B.V., 2015. All rights reserved.
Alex Young 18:2073072bad51 5 *
Alex Young 18:2073072bad51 6 * This source code is intended for use only by Xsens Technologies BV and
Alex Young 18:2073072bad51 7 * those that have explicit written permission to use it from
Alex Young 18:2073072bad51 8 * Xsens Technologies BV.
Alex Young 18:2073072bad51 9 *
Alex Young 18:2073072bad51 10 * THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
Alex Young 18:2073072bad51 11 * KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
Alex Young 18:2073072bad51 12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
Alex Young 18:2073072bad51 13 * PARTICULAR PURPOSE.
Alex Young 18:2073072bad51 14 */
Alex Young 18:2073072bad51 15
Alex Young 18:2073072bad51 16 #include "xbusmessage.h"
Alex Young 18:2073072bad51 17 #include "xbusdef.h"
Alex Young 18:2073072bad51 18 #include "xbusutility.h"
Alex Young 18:2073072bad51 19
Alex Young 48:69d35430fe8b 20 /*!
Alex Young 48:69d35430fe8b 21 * \brief Calculate the number of bytes needed for \a message payload.
Alex Young 48:69d35430fe8b 22 */
Alex Young 28:ae74baf7e5ab 23 static uint16_t messageLength(struct XbusMessage const* message)
Alex Young 28:ae74baf7e5ab 24 {
Alex Young 28:ae74baf7e5ab 25 switch (message->mid)
Alex Young 28:ae74baf7e5ab 26 {
Alex Young 28:ae74baf7e5ab 27 case XMID_SetOutputConfig:
Alex Young 28:ae74baf7e5ab 28 return message->length * 2 * sizeof(uint16_t);
Alex Young 28:ae74baf7e5ab 29
Alex Young 28:ae74baf7e5ab 30 default:
Alex Young 28:ae74baf7e5ab 31 return message->length;
Alex Young 28:ae74baf7e5ab 32 }
Alex Young 28:ae74baf7e5ab 33 }
Alex Young 28:ae74baf7e5ab 34
Alex Young 48:69d35430fe8b 35 /*!
Alex Young 48:69d35430fe8b 36 * \brief Format a message with a pointer to an array of OutputConfiguration elements.
Alex Young 48:69d35430fe8b 37 */
Alex Young 28:ae74baf7e5ab 38 static void formatOutputConfig(uint8_t* raw, struct XbusMessage const* message)
Alex Young 28:ae74baf7e5ab 39 {
Alex Young 28:ae74baf7e5ab 40 struct OutputConfiguration* conf = message->data;
Alex Young 28:ae74baf7e5ab 41 for (int i = 0; i < message->length; ++i)
Alex Young 28:ae74baf7e5ab 42 {
Alex Young 28:ae74baf7e5ab 43 raw = XbusUtility_writeU16(raw, conf->dtype);
Alex Young 28:ae74baf7e5ab 44 raw = XbusUtility_writeU16(raw, conf->freq);
Alex Young 28:ae74baf7e5ab 45 ++conf;
Alex Young 28:ae74baf7e5ab 46 }
Alex Young 28:ae74baf7e5ab 47 }
Alex Young 28:ae74baf7e5ab 48
Alex Young 48:69d35430fe8b 49 /*!
Alex Young 48:69d35430fe8b 50 * \brief Format the payload of a message from a native data type to
Alex Young 48:69d35430fe8b 51 * raw bytes.
Alex Young 48:69d35430fe8b 52 */
Alex Young 28:ae74baf7e5ab 53 static void formatPayload(uint8_t* raw, struct XbusMessage const* message)
Alex Young 28:ae74baf7e5ab 54 {
Alex Young 28:ae74baf7e5ab 55 switch (message->mid)
Alex Young 28:ae74baf7e5ab 56 {
Alex Young 28:ae74baf7e5ab 57 case XMID_SetOutputConfig:
Alex Young 28:ae74baf7e5ab 58 formatOutputConfig(raw, message);
Alex Young 28:ae74baf7e5ab 59 break;
Alex Young 28:ae74baf7e5ab 60
Alex Young 28:ae74baf7e5ab 61 default:
Alex Young 28:ae74baf7e5ab 62 for (int i = 0; i < message->length; ++i)
Alex Young 28:ae74baf7e5ab 63 {
Alex Young 28:ae74baf7e5ab 64 *raw++ = ((uint8_t*)message->data)[i];
Alex Young 28:ae74baf7e5ab 65 }
Alex Young 28:ae74baf7e5ab 66 break;
Alex Young 28:ae74baf7e5ab 67 }
Alex Young 28:ae74baf7e5ab 68 }
Alex Young 28:ae74baf7e5ab 69
Alex Young 48:69d35430fe8b 70 /*!
Alex Young 48:69d35430fe8b 71 * \brief Format a message into the raw Xbus format ready for transmission to
Alex Young 48:69d35430fe8b 72 * a motion tracker.
Alex Young 48:69d35430fe8b 73 */
Alex Young 18:2073072bad51 74 size_t XbusMessage_format(uint8_t* raw, struct XbusMessage const* message)
Alex Young 18:2073072bad51 75 {
Alex Young 18:2073072bad51 76 uint8_t* dptr = raw;
Alex Young 18:2073072bad51 77 *dptr++ = XBUS_PREAMBLE;
Alex Young 18:2073072bad51 78
Alex Young 18:2073072bad51 79 *dptr = XBUS_BUS_ID_STANDALONE;
Alex Young 18:2073072bad51 80 uint8_t checksum = 0;
Alex Young 18:2073072bad51 81 checksum -= *dptr++;
Alex Young 18:2073072bad51 82
Alex Young 18:2073072bad51 83 *dptr = message->mid;
Alex Young 18:2073072bad51 84 checksum -= *dptr++;
Alex Young 18:2073072bad51 85
Alex Young 28:ae74baf7e5ab 86 uint16_t length = messageLength(message);
Alex Young 28:ae74baf7e5ab 87
Alex Young 28:ae74baf7e5ab 88 if (length < XBUS_EXTENDED_LENGTH)
Alex Young 18:2073072bad51 89 {
Alex Young 28:ae74baf7e5ab 90 *dptr = length;
Alex Young 18:2073072bad51 91 checksum -= *dptr++;
Alex Young 18:2073072bad51 92 }
Alex Young 18:2073072bad51 93 else
Alex Young 18:2073072bad51 94 {
Alex Young 18:2073072bad51 95 *dptr = XBUS_EXTENDED_LENGTH;
Alex Young 18:2073072bad51 96 checksum -= *dptr++;
Alex Young 28:ae74baf7e5ab 97 *dptr = length >> 8;
Alex Young 18:2073072bad51 98 checksum -= *dptr++;
Alex Young 28:ae74baf7e5ab 99 *dptr = length & 0xFF;
Alex Young 18:2073072bad51 100 checksum -= *dptr++;
Alex Young 18:2073072bad51 101 }
Alex Young 18:2073072bad51 102
Alex Young 28:ae74baf7e5ab 103 formatPayload(dptr, message);
Alex Young 28:ae74baf7e5ab 104 for (int i = 0; i < length; ++i)
Alex Young 18:2073072bad51 105 {
Alex Young 18:2073072bad51 106 checksum -= *dptr++;
Alex Young 18:2073072bad51 107 }
Alex Young 18:2073072bad51 108 *dptr++ = checksum;
Alex Young 18:2073072bad51 109
Alex Young 18:2073072bad51 110 return dptr - raw;
Alex Young 18:2073072bad51 111 }
Alex Young 18:2073072bad51 112
Alex Young 48:69d35430fe8b 113 /*!
Alex Young 48:69d35430fe8b 114 * \brief Get a pointer to the data correspondind to \a id.
Alex Young 48:69d35430fe8b 115 * \param id The data identifier to find in the message.
Alex Young 48:69d35430fe8b 116 * \param data Pointer to the raw message payload.
Alex Young 48:69d35430fe8b 117 * \param dataLength The length of the payload in bytes.
Alex Young 48:69d35430fe8b 118 * \returns Pointer to data item, or NULL if the identifier is not present in
Alex Young 48:69d35430fe8b 119 * the message.
Alex Young 48:69d35430fe8b 120 */
Alex Young 18:2073072bad51 121 static uint8_t const* getPointerToData(enum XsDataIdentifier id, uint8_t const* data, uint16_t dataLength)
Alex Young 18:2073072bad51 122 {
Alex Young 18:2073072bad51 123 uint8_t const* dptr = data;
Alex Young 18:2073072bad51 124 while (dptr < data + dataLength)
Alex Young 18:2073072bad51 125 {
Alex Young 18:2073072bad51 126 uint16_t itemId;
Alex Young 18:2073072bad51 127 uint8_t itemSize;
Alex Young 18:2073072bad51 128 dptr = XbusUtility_readU16(&itemId, dptr);
Alex Young 18:2073072bad51 129 dptr = XbusUtility_readU8(&itemSize, dptr);
Alex Young 18:2073072bad51 130
Alex Young 18:2073072bad51 131 if (id == itemId)
Alex Young 18:2073072bad51 132 return dptr;
Alex Young 18:2073072bad51 133
Alex Young 18:2073072bad51 134 dptr += itemSize;
Alex Young 18:2073072bad51 135 }
Alex Young 18:2073072bad51 136 return NULL;
Alex Young 18:2073072bad51 137 }
Alex Young 18:2073072bad51 138
Alex Young 48:69d35430fe8b 139 /*!
Alex Young 48:69d35430fe8b 140 * \brief Read a number of floats from a message payload.
Alex Young 48:69d35430fe8b 141 * \param out Pointer to where to output data.
Alex Young 48:69d35430fe8b 142 * \param raw Pointer to the start of the raw float data.
Alex Young 48:69d35430fe8b 143 * \param floats The number of floats to read.
Alex Young 48:69d35430fe8b 144 */
Alex Young 18:2073072bad51 145 static void readFloats(float* out, uint8_t const* raw, uint8_t floats)
Alex Young 18:2073072bad51 146 {
Alex Young 18:2073072bad51 147 for (int i = 0; i < floats; ++i)
Alex Young 18:2073072bad51 148 {
Alex Young 18:2073072bad51 149 raw = XbusUtility_readU32((uint32_t*)&out[i], raw);
Alex Young 18:2073072bad51 150 }
Alex Young 18:2073072bad51 151 }
Alex Young 18:2073072bad51 152
Alex Young 48:69d35430fe8b 153 /*!
Alex Young 48:69d35430fe8b 154 * \brief Get a data item from a XMID_MtData2 Xbus message.
Alex Young 48:69d35430fe8b 155 * \param item Pointer to where to store the data.
Alex Young 48:69d35430fe8b 156 * \param id The data identifier to get.
Alex Young 48:69d35430fe8b 157 * \param message The message to read the data item from.
Alex Young 48:69d35430fe8b 158 * \returns true if the data item is found in the message, else false.
Alex Young 48:69d35430fe8b 159 */
Alex Young 18:2073072bad51 160 bool XbusMessage_getDataItem(void* item, enum XsDataIdentifier id, struct XbusMessage const* message)
Alex Young 18:2073072bad51 161 {
Alex Young 18:2073072bad51 162 uint8_t const* raw = getPointerToData(id, message->data, message->length);
Alex Young 18:2073072bad51 163 if (raw)
Alex Young 18:2073072bad51 164 {
Alex Young 18:2073072bad51 165 switch (id)
Alex Young 18:2073072bad51 166 {
Alex Young 18:2073072bad51 167 case XDI_PacketCounter:
Alex Young 18:2073072bad51 168 raw = XbusUtility_readU16(item, raw);
Alex Young 18:2073072bad51 169 break;
Alex Young 18:2073072bad51 170
Alex Young 18:2073072bad51 171 case XDI_SampleTimeFine:
Alex Young 18:2073072bad51 172 case XDI_StatusWord:
Alex Young 18:2073072bad51 173 raw = XbusUtility_readU32(item, raw);
Alex Young 18:2073072bad51 174 break;
Alex Young 18:2073072bad51 175
Alex Young 18:2073072bad51 176 case XDI_Quaternion:
Alex Young 18:2073072bad51 177 case XDI_DeltaQ:
Alex Young 18:2073072bad51 178 readFloats(item, raw, 4);
Alex Young 18:2073072bad51 179 break;
Alex Young 18:2073072bad51 180
Alex Young 18:2073072bad51 181 case XDI_DeltaV:
Alex Young 18:2073072bad51 182 case XDI_Acceleration:
Alex Young 18:2073072bad51 183 case XDI_RateOfTurn:
Alex Young 18:2073072bad51 184 case XDI_MagneticField:
Alex Young 18:2073072bad51 185 readFloats(item, raw, 3);
Alex Young 18:2073072bad51 186 break;
Alex Young 18:2073072bad51 187
Alex Young 18:2073072bad51 188 default:
Alex Young 18:2073072bad51 189 return false;
Alex Young 18:2073072bad51 190 }
Alex Young 18:2073072bad51 191 return true;
Alex Young 18:2073072bad51 192 }
Alex Young 18:2073072bad51 193 else
Alex Young 18:2073072bad51 194 {
Alex Young 18:2073072bad51 195 return false;
Alex Young 18:2073072bad51 196 }
Alex Young 18:2073072bad51 197 }
Alex Young 18:2073072bad51 198
Alex Young 48:69d35430fe8b 199 /*!
Alex Young 48:69d35430fe8b 200 * \brief Get a string descriptions for the passed data identifier.
Alex Young 48:69d35430fe8b 201 */
Alex Young 21:6015b8be3a00 202 char const* XbusMessage_dataDescription(enum XsDataIdentifier id)
Alex Young 21:6015b8be3a00 203 {
Alex Young 21:6015b8be3a00 204 switch (id)
Alex Young 21:6015b8be3a00 205 {
Alex Young 21:6015b8be3a00 206 case XDI_PacketCounter:
Alex Young 21:6015b8be3a00 207 return "Packet counter";
Alex Young 21:6015b8be3a00 208
Alex Young 21:6015b8be3a00 209 case XDI_SampleTimeFine:
Alex Young 21:6015b8be3a00 210 return "Sample time fine";
Alex Young 21:6015b8be3a00 211
Alex Young 21:6015b8be3a00 212 case XDI_Quaternion:
Alex Young 21:6015b8be3a00 213 return "Quaternion";
Alex Young 21:6015b8be3a00 214
Alex Young 21:6015b8be3a00 215 case XDI_DeltaV:
Alex Young 21:6015b8be3a00 216 return "Velocity increment";
Alex Young 21:6015b8be3a00 217
Alex Young 21:6015b8be3a00 218 case XDI_Acceleration:
Alex Young 21:6015b8be3a00 219 return "Acceleration";
Alex Young 21:6015b8be3a00 220
Alex Young 21:6015b8be3a00 221 case XDI_RateOfTurn:
Alex Young 21:6015b8be3a00 222 return "Rate of turn";
Alex Young 21:6015b8be3a00 223
Alex Young 21:6015b8be3a00 224 case XDI_DeltaQ:
Alex Young 21:6015b8be3a00 225 return "Orientation increment";
Alex Young 21:6015b8be3a00 226
Alex Young 21:6015b8be3a00 227 case XDI_MagneticField:
Alex Young 21:6015b8be3a00 228 return "Magnetic field";
Alex Young 21:6015b8be3a00 229
Alex Young 21:6015b8be3a00 230 case XDI_StatusWord:
Alex Young 21:6015b8be3a00 231 return "Status word";
Alex Young 21:6015b8be3a00 232
Alex Young 21:6015b8be3a00 233 default:
Alex Young 21:6015b8be3a00 234 return "Unknown data type";
Alex Young 21:6015b8be3a00 235 }
Alex Young 21:6015b8be3a00 236 }