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This example is deprecated and no longer maintained.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:
Tue May 19 13:40:33 2015 +0200
Revision:
16:4bdcdac223d8
Parent:
10:18a6661b7e59
Child:
18:2073072bad51
Move MtData2 parsing to xbus message module

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Alex Young 10:18a6661b7e59 1 /*!
Alex Young 10:18a6661b7e59 2 * \file
Alex Young 10:18a6661b7e59 3 * \copyright
Alex Young 10:18a6661b7e59 4 * Copyright (C) Xsens Technologies B.V., 2015. All rights reserved.
Alex Young 10:18a6661b7e59 5 *
Alex Young 10:18a6661b7e59 6 * This source code is intended for use only by Xsens Technologies BV and
Alex Young 10:18a6661b7e59 7 * those that have explicit written permission to use it from
Alex Young 10:18a6661b7e59 8 * Xsens Technologies BV.
Alex Young 10:18a6661b7e59 9 *
Alex Young 10:18a6661b7e59 10 * THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
Alex Young 10:18a6661b7e59 11 * KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
Alex Young 10:18a6661b7e59 12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
Alex Young 10:18a6661b7e59 13 * PARTICULAR PURPOSE.
Alex Young 10:18a6661b7e59 14 */
Alex Young 10:18a6661b7e59 15
Alex Young 10:18a6661b7e59 16 #include "xbusmessage.h"
Alex Young 10:18a6661b7e59 17 #include "xbusdef.h"
Alex Young 10:18a6661b7e59 18
Alex Young 10:18a6661b7e59 19 size_t XbusMessage_format(uint8_t* raw, struct XbusMessage const* message)
Alex Young 10:18a6661b7e59 20 {
Alex Young 10:18a6661b7e59 21 uint8_t* dptr = raw;
Alex Young 10:18a6661b7e59 22 *dptr++ = XBUS_PREAMBLE;
Alex Young 10:18a6661b7e59 23
Alex Young 10:18a6661b7e59 24 *dptr = XBUS_BUS_ID_STANDALONE;
Alex Young 10:18a6661b7e59 25 uint8_t checksum = 0;
Alex Young 10:18a6661b7e59 26 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 27
Alex Young 10:18a6661b7e59 28 *dptr = message->mid;
Alex Young 10:18a6661b7e59 29 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 30
Alex Young 10:18a6661b7e59 31 if (message->length < XBUS_EXTENDED_LENGTH)
Alex Young 10:18a6661b7e59 32 {
Alex Young 10:18a6661b7e59 33 *dptr = message->length;
Alex Young 10:18a6661b7e59 34 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 35 }
Alex Young 10:18a6661b7e59 36 else
Alex Young 10:18a6661b7e59 37 {
Alex Young 10:18a6661b7e59 38 *dptr = XBUS_EXTENDED_LENGTH;
Alex Young 10:18a6661b7e59 39 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 40 *dptr = message->length >> 8;
Alex Young 10:18a6661b7e59 41 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 42 *dptr = message->length & 0xFF;
Alex Young 10:18a6661b7e59 43 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 44 }
Alex Young 10:18a6661b7e59 45
Alex Young 10:18a6661b7e59 46 uint8_t* sptr = message->data;
Alex Young 10:18a6661b7e59 47 for (int i = 0; i < message->length; ++i)
Alex Young 10:18a6661b7e59 48 {
Alex Young 10:18a6661b7e59 49 *dptr = *sptr++;
Alex Young 10:18a6661b7e59 50 checksum -= *dptr++;
Alex Young 10:18a6661b7e59 51 }
Alex Young 10:18a6661b7e59 52 *dptr++ = checksum;
Alex Young 10:18a6661b7e59 53
Alex Young 10:18a6661b7e59 54 return dptr - raw;
Alex Young 10:18a6661b7e59 55 }
Alex Young 10:18a6661b7e59 56
Alex Young 16:4bdcdac223d8 57 static uint8_t const* getPointerToData(enum XsDataIdentifier id, uint8_t const* data, uint16_t dataLength)
Alex Young 16:4bdcdac223d8 58 {
Alex Young 16:4bdcdac223d8 59 uint8_t const* dptr = data;
Alex Young 16:4bdcdac223d8 60 while (dptr < data + dataLength)
Alex Young 16:4bdcdac223d8 61 {
Alex Young 16:4bdcdac223d8 62 const uint16_t itemId = (dptr[0] << 8) | dptr[1];
Alex Young 16:4bdcdac223d8 63 dptr += sizeof(itemId);
Alex Young 16:4bdcdac223d8 64 const uint8_t itemSize = *dptr++;
Alex Young 16:4bdcdac223d8 65
Alex Young 16:4bdcdac223d8 66 if (id == itemId)
Alex Young 16:4bdcdac223d8 67 return dptr;
Alex Young 16:4bdcdac223d8 68
Alex Young 16:4bdcdac223d8 69 dptr += itemSize;
Alex Young 16:4bdcdac223d8 70 }
Alex Young 16:4bdcdac223d8 71 return NULL;
Alex Young 16:4bdcdac223d8 72 }
Alex Young 16:4bdcdac223d8 73
Alex Young 16:4bdcdac223d8 74 static void readShort(uint16_t* out, uint8_t const* raw)
Alex Young 16:4bdcdac223d8 75 {
Alex Young 16:4bdcdac223d8 76 *out = (raw[0] << 8) | raw[1];
Alex Young 16:4bdcdac223d8 77 }
Alex Young 16:4bdcdac223d8 78
Alex Young 16:4bdcdac223d8 79 static void readInt(uint32_t* out, uint8_t const* raw)
Alex Young 16:4bdcdac223d8 80 {
Alex Young 16:4bdcdac223d8 81 *out = (raw[0] << 24) | (raw[1] << 16) | (raw[2] << 8) | raw[3];
Alex Young 16:4bdcdac223d8 82 }
Alex Young 16:4bdcdac223d8 83
Alex Young 16:4bdcdac223d8 84 static void readFloats(float* out, uint8_t const* raw, uint8_t floats)
Alex Young 16:4bdcdac223d8 85 {
Alex Young 16:4bdcdac223d8 86 for (int i = 0; i < floats; ++i)
Alex Young 16:4bdcdac223d8 87 {
Alex Young 16:4bdcdac223d8 88 readInt((uint32_t*)&out[i], &raw[i * sizeof(float)]);
Alex Young 16:4bdcdac223d8 89 }
Alex Young 16:4bdcdac223d8 90 }
Alex Young 16:4bdcdac223d8 91
Alex Young 16:4bdcdac223d8 92 bool XbusMessage_getDataItem(void* item, enum XsDataIdentifier id, struct XbusMessage const* message)
Alex Young 16:4bdcdac223d8 93 {
Alex Young 16:4bdcdac223d8 94 uint8_t const* raw = getPointerToData(id, message->data, message->length);
Alex Young 16:4bdcdac223d8 95 if (raw)
Alex Young 16:4bdcdac223d8 96 {
Alex Young 16:4bdcdac223d8 97 switch (id)
Alex Young 16:4bdcdac223d8 98 {
Alex Young 16:4bdcdac223d8 99 case XDI_PacketCounter:
Alex Young 16:4bdcdac223d8 100 readShort(item, raw);
Alex Young 16:4bdcdac223d8 101 break;
Alex Young 16:4bdcdac223d8 102
Alex Young 16:4bdcdac223d8 103 case XDI_SampleTimeFine:
Alex Young 16:4bdcdac223d8 104 case XDI_StatusWord:
Alex Young 16:4bdcdac223d8 105 readInt(item, raw);
Alex Young 16:4bdcdac223d8 106 break;
Alex Young 16:4bdcdac223d8 107
Alex Young 16:4bdcdac223d8 108 case XDI_Quaternion:
Alex Young 16:4bdcdac223d8 109 case XDI_DeltaQ:
Alex Young 16:4bdcdac223d8 110 readFloats(item, raw, 4);
Alex Young 16:4bdcdac223d8 111 break;
Alex Young 16:4bdcdac223d8 112
Alex Young 16:4bdcdac223d8 113 case XDI_DeltaV:
Alex Young 16:4bdcdac223d8 114 case XDI_Acceleration:
Alex Young 16:4bdcdac223d8 115 case XDI_RateOfTurn:
Alex Young 16:4bdcdac223d8 116 case XDI_MagneticField:
Alex Young 16:4bdcdac223d8 117 readFloats(item, raw, 3);
Alex Young 16:4bdcdac223d8 118 break;
Alex Young 16:4bdcdac223d8 119
Alex Young 16:4bdcdac223d8 120 default:
Alex Young 16:4bdcdac223d8 121 return false;
Alex Young 16:4bdcdac223d8 122 }
Alex Young 16:4bdcdac223d8 123 return true;
Alex Young 16:4bdcdac223d8 124 }
Alex Young 16:4bdcdac223d8 125 else
Alex Young 16:4bdcdac223d8 126 {
Alex Young 16:4bdcdac223d8 127 return false;
Alex Young 16:4bdcdac223d8 128 }
Alex Young 16:4bdcdac223d8 129 }
Alex Young 16:4bdcdac223d8 130