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This example is deprecated and no longer maintained.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:
Wed May 20 12:39:11 2015 +0200
Revision:
23:8171449f0dc3
Parent:
22:3eab999c5076
Child:
25:01356fb59467
Factor out specific message parsing functions.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Alex Young 3:abc451d82b88 1 /*!
Alex Young 3:abc451d82b88 2 * \file
Alex Young 3:abc451d82b88 3 * \copyright
Alex Young 3:abc451d82b88 4 * Copyright (C) Xsens Technologies B.V., 2015. All rights reserved.
Alex Young 3:abc451d82b88 5 *
Alex Young 3:abc451d82b88 6 * This source code is intended for use only by Xsens Technologies BV and
Alex Young 3:abc451d82b88 7 * those that have explicit written permission to use it from
Alex Young 3:abc451d82b88 8 * Xsens Technologies BV.
Alex Young 3:abc451d82b88 9 *
Alex Young 3:abc451d82b88 10 * THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
Alex Young 3:abc451d82b88 11 * KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
Alex Young 3:abc451d82b88 12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
Alex Young 3:abc451d82b88 13 * PARTICULAR PURPOSE.
Alex Young 3:abc451d82b88 14 */
Alex Young 3:abc451d82b88 15
Alex Young 3:abc451d82b88 16 #include "xbusparser.h"
Alex Young 10:18a6661b7e59 17 #include "xbusdef.h"
Alex Young 19:46e88d37ecef 18 #include "xbusutility.h"
Alex Young 3:abc451d82b88 19 #include <stdlib.h>
Alex Young 19:46e88d37ecef 20 #include <string.h>
Alex Young 19:46e88d37ecef 21 #include <assert.h>
Alex Young 19:46e88d37ecef 22
Alex Young 19:46e88d37ecef 23 /*!
Alex Young 19:46e88d37ecef 24 * \brief Max message length for parsed message types.
Alex Young 19:46e88d37ecef 25 * Unparsed types, e.g. MtData2 packets, will have buffers dynamically
Alex Young 19:46e88d37ecef 26 * requested, so are not constrained by this value.
Alex Young 19:46e88d37ecef 27 */
Alex Young 19:46e88d37ecef 28 #define XBUS_MAX_MESSAGE_LENGTH (64)
Alex Young 3:abc451d82b88 29
Alex Young 3:abc451d82b88 30 enum XbusParserState
Alex Young 3:abc451d82b88 31 {
Alex Young 3:abc451d82b88 32 XBPS_Preamble, /*!< \brief Looking for preamble. */
Alex Young 3:abc451d82b88 33 XBPS_BusId, /*!< \brief Waiting for bus ID. */
Alex Young 3:abc451d82b88 34 XBPS_MessageId, /*!< \brief Waiting for message ID. */
Alex Young 3:abc451d82b88 35 XBPS_Length, /*!< \brief Waiting for length. */
Alex Young 3:abc451d82b88 36 XBPS_ExtendedLengthMsb, /*!< \brief Waiting for extended length MSB*/
Alex Young 3:abc451d82b88 37 XBPS_ExtendedLengthLsb, /*!< \brief Waiting for extended length LSB*/
Alex Young 3:abc451d82b88 38 XBPS_Payload, /*!< \brief Reading payload. */
Alex Young 3:abc451d82b88 39 XBPS_Checksum /*!< \brief Waiting for checksum. */
Alex Young 3:abc451d82b88 40 };
Alex Young 3:abc451d82b88 41
Alex Young 3:abc451d82b88 42 struct XbusParser
Alex Young 3:abc451d82b88 43 {
Alex Young 3:abc451d82b88 44 struct XbusParserCallback callbacks;
Alex Young 14:155f9a55ec51 45 struct XbusMessage currentMessage;
Alex Young 19:46e88d37ecef 46 uint8_t rxBuffer[XBUS_MAX_MESSAGE_LENGTH];
Alex Young 3:abc451d82b88 47 uint16_t payloadReceived;
Alex Young 3:abc451d82b88 48 uint8_t checksum;
Alex Young 3:abc451d82b88 49 enum XbusParserState state;
Alex Young 3:abc451d82b88 50 };
Alex Young 3:abc451d82b88 51
Alex Young 3:abc451d82b88 52 size_t XbusParser_mem(void)
Alex Young 3:abc451d82b88 53 {
Alex Young 3:abc451d82b88 54 return sizeof(struct XbusParser);
Alex Young 3:abc451d82b88 55 }
Alex Young 3:abc451d82b88 56
Alex Young 3:abc451d82b88 57 struct XbusParser* XbusParser_create(struct XbusParserCallback const* callback)
Alex Young 3:abc451d82b88 58 {
Alex Young 3:abc451d82b88 59 void* mem = malloc(XbusParser_mem());
Alex Young 3:abc451d82b88 60 if (mem)
Alex Young 3:abc451d82b88 61 {
Alex Young 3:abc451d82b88 62 return XbusParser_init(mem, callback);
Alex Young 3:abc451d82b88 63 }
Alex Young 3:abc451d82b88 64 return NULL;
Alex Young 3:abc451d82b88 65 }
Alex Young 3:abc451d82b88 66
Alex Young 3:abc451d82b88 67 void XbusParser_destroy(struct XbusParser* parser)
Alex Young 3:abc451d82b88 68 {
Alex Young 3:abc451d82b88 69 free(parser);
Alex Young 3:abc451d82b88 70 }
Alex Young 3:abc451d82b88 71
Alex Young 3:abc451d82b88 72 struct XbusParser* XbusParser_init(void* parserMem, struct XbusParserCallback const* callback)
Alex Young 3:abc451d82b88 73 {
Alex Young 3:abc451d82b88 74 struct XbusParser* parser = (struct XbusParser*)parserMem;
Alex Young 3:abc451d82b88 75 parser->state = XBPS_Preamble;
Alex Young 3:abc451d82b88 76 parser->callbacks.allocateBuffer = callback->allocateBuffer;
Alex Young 3:abc451d82b88 77 parser->callbacks.handleMessage = callback->handleMessage;
Alex Young 3:abc451d82b88 78 return parser;
Alex Young 3:abc451d82b88 79 }
Alex Young 3:abc451d82b88 80
Alex Young 19:46e88d37ecef 81 static bool canParseMessagePayload(enum XsMessageId mid)
Alex Young 19:46e88d37ecef 82 {
Alex Young 19:46e88d37ecef 83 switch (mid)
Alex Young 19:46e88d37ecef 84 {
Alex Young 19:46e88d37ecef 85 case XMID_DeviceId:
Alex Young 22:3eab999c5076 86 case XMID_OutputConfig:
Alex Young 19:46e88d37ecef 87 return true;
Alex Young 19:46e88d37ecef 88
Alex Young 19:46e88d37ecef 89 default:
Alex Young 19:46e88d37ecef 90 return false;
Alex Young 19:46e88d37ecef 91 }
Alex Young 19:46e88d37ecef 92 }
Alex Young 19:46e88d37ecef 93
Alex Young 23:8171449f0dc3 94 static void parseDeviceId(struct XbusParser* parser)
Alex Young 23:8171449f0dc3 95 {
Alex Young 23:8171449f0dc3 96 uint32_t* deviceId = parser->callbacks.allocateBuffer(sizeof(uint32_t));
Alex Young 23:8171449f0dc3 97 if (deviceId)
Alex Young 23:8171449f0dc3 98 {
Alex Young 23:8171449f0dc3 99 XbusUtility_readU32(deviceId, parser->rxBuffer);
Alex Young 23:8171449f0dc3 100 parser->currentMessage.data = deviceId;
Alex Young 23:8171449f0dc3 101 parser->currentMessage.length = 1;
Alex Young 23:8171449f0dc3 102 }
Alex Young 23:8171449f0dc3 103 else
Alex Young 23:8171449f0dc3 104 {
Alex Young 23:8171449f0dc3 105 parser->currentMessage.data = NULL;
Alex Young 23:8171449f0dc3 106 }
Alex Young 23:8171449f0dc3 107 }
Alex Young 23:8171449f0dc3 108
Alex Young 23:8171449f0dc3 109 static void parseOutputConfig(struct XbusParser* parser)
Alex Young 23:8171449f0dc3 110 {
Alex Young 23:8171449f0dc3 111 uint8_t fields = parser->currentMessage.length / 4;
Alex Young 23:8171449f0dc3 112 struct OutputConfiguration* conf = parser->callbacks.allocateBuffer(fields * sizeof(struct OutputConfiguration));
Alex Young 23:8171449f0dc3 113 uint8_t const* dptr = parser->rxBuffer;
Alex Young 23:8171449f0dc3 114 if (conf)
Alex Young 23:8171449f0dc3 115 {
Alex Young 23:8171449f0dc3 116 parser->currentMessage.data = conf;
Alex Young 23:8171449f0dc3 117 parser->currentMessage.length = fields;
Alex Young 23:8171449f0dc3 118
Alex Young 23:8171449f0dc3 119 for (int i = 0; i < fields; ++i)
Alex Young 23:8171449f0dc3 120 {
Alex Young 23:8171449f0dc3 121 dptr = XbusUtility_readU16((uint16_t*)&conf->dtype, dptr);
Alex Young 23:8171449f0dc3 122 dptr = XbusUtility_readU16(&conf->freq, dptr);
Alex Young 23:8171449f0dc3 123 ++conf;
Alex Young 23:8171449f0dc3 124 }
Alex Young 23:8171449f0dc3 125 }
Alex Young 23:8171449f0dc3 126 else
Alex Young 23:8171449f0dc3 127 {
Alex Young 23:8171449f0dc3 128 parser->currentMessage.data = NULL;
Alex Young 23:8171449f0dc3 129 }
Alex Young 23:8171449f0dc3 130 }
Alex Young 23:8171449f0dc3 131
Alex Young 19:46e88d37ecef 132 static void parseMessagePayload(struct XbusParser* parser)
Alex Young 3:abc451d82b88 133 {
Alex Young 19:46e88d37ecef 134 switch (parser->currentMessage.mid)
Alex Young 19:46e88d37ecef 135 {
Alex Young 19:46e88d37ecef 136 case XMID_DeviceId:
Alex Young 23:8171449f0dc3 137 parseDeviceId(parser);
Alex Young 19:46e88d37ecef 138 break;
Alex Young 19:46e88d37ecef 139
Alex Young 22:3eab999c5076 140 case XMID_OutputConfig:
Alex Young 23:8171449f0dc3 141 parseOutputConfig(parser);
Alex Young 22:3eab999c5076 142 break;
Alex Young 22:3eab999c5076 143
Alex Young 19:46e88d37ecef 144 default:
Alex Young 19:46e88d37ecef 145 assert(!canParseMessagePayload(parser->currentMessage.mid));
Alex Young 19:46e88d37ecef 146 break;
Alex Young 19:46e88d37ecef 147 }
Alex Young 19:46e88d37ecef 148 }
Alex Young 19:46e88d37ecef 149
Alex Young 19:46e88d37ecef 150 void prepareForPayload(struct XbusParser* parser)
Alex Young 19:46e88d37ecef 151 {
Alex Young 19:46e88d37ecef 152 parser->currentMessage.data = NULL;
Alex Young 3:abc451d82b88 153 parser->payloadReceived = 0;
Alex Young 19:46e88d37ecef 154
Alex Young 19:46e88d37ecef 155 if (canParseMessagePayload(parser->currentMessage.mid))
Alex Young 19:46e88d37ecef 156 {
Alex Young 19:46e88d37ecef 157 assert(parser->currentMessage.length < XBUS_MAX_MESSAGE_LENGTH);
Alex Young 19:46e88d37ecef 158 if (parser->currentMessage.length < XBUS_MAX_MESSAGE_LENGTH)
Alex Young 19:46e88d37ecef 159 {
Alex Young 19:46e88d37ecef 160 parser->currentMessage.data = parser->rxBuffer;
Alex Young 19:46e88d37ecef 161 }
Alex Young 19:46e88d37ecef 162 }
Alex Young 19:46e88d37ecef 163 else
Alex Young 19:46e88d37ecef 164 {
Alex Young 19:46e88d37ecef 165 parser->currentMessage.data = parser->callbacks.allocateBuffer(parser->currentMessage.length);
Alex Young 19:46e88d37ecef 166 }
Alex Young 3:abc451d82b88 167 }
Alex Young 3:abc451d82b88 168
Alex Young 3:abc451d82b88 169 void XbusParser_parseByte(struct XbusParser* parser, const uint8_t byte)
Alex Young 3:abc451d82b88 170 {
Alex Young 3:abc451d82b88 171 switch (parser->state)
Alex Young 3:abc451d82b88 172 {
Alex Young 3:abc451d82b88 173 case XBPS_Preamble:
Alex Young 3:abc451d82b88 174 if (byte == XBUS_PREAMBLE)
Alex Young 3:abc451d82b88 175 {
Alex Young 3:abc451d82b88 176 parser->checksum = 0;
Alex Young 3:abc451d82b88 177 parser->state = XBPS_BusId;
Alex Young 3:abc451d82b88 178 }
Alex Young 3:abc451d82b88 179 break;
Alex Young 3:abc451d82b88 180
Alex Young 3:abc451d82b88 181 case XBPS_BusId:
Alex Young 3:abc451d82b88 182 parser->checksum += byte;
Alex Young 3:abc451d82b88 183 parser->state = XBPS_MessageId;
Alex Young 3:abc451d82b88 184 break;
Alex Young 3:abc451d82b88 185
Alex Young 3:abc451d82b88 186 case XBPS_MessageId:
Alex Young 3:abc451d82b88 187 parser->checksum += byte;
Alex Young 14:155f9a55ec51 188 parser->currentMessage.mid = (enum XsMessageId)byte;
Alex Young 3:abc451d82b88 189 parser->state = XBPS_Length;
Alex Young 3:abc451d82b88 190 break;
Alex Young 3:abc451d82b88 191
Alex Young 3:abc451d82b88 192 case XBPS_Length:
Alex Young 3:abc451d82b88 193 parser->checksum += byte;
Alex Young 3:abc451d82b88 194 if (byte == XBUS_NO_PAYLOAD)
Alex Young 3:abc451d82b88 195 {
Alex Young 14:155f9a55ec51 196 parser->currentMessage.length = byte;
Alex Young 17:680f28e00d17 197 parser->currentMessage.data = NULL;
Alex Young 3:abc451d82b88 198 parser->state = XBPS_Checksum;
Alex Young 3:abc451d82b88 199 }
Alex Young 3:abc451d82b88 200 else if (byte < XBUS_EXTENDED_LENGTH)
Alex Young 3:abc451d82b88 201 {
Alex Young 14:155f9a55ec51 202 parser->currentMessage.length = byte;
Alex Young 3:abc451d82b88 203 prepareForPayload(parser);
Alex Young 3:abc451d82b88 204 parser->state = XBPS_Payload;
Alex Young 3:abc451d82b88 205 }
Alex Young 3:abc451d82b88 206 else
Alex Young 3:abc451d82b88 207 {
Alex Young 3:abc451d82b88 208 parser->state = XBPS_ExtendedLengthMsb;
Alex Young 3:abc451d82b88 209 }
Alex Young 3:abc451d82b88 210 break;
Alex Young 3:abc451d82b88 211
Alex Young 3:abc451d82b88 212 case XBPS_ExtendedLengthMsb:
Alex Young 3:abc451d82b88 213 parser->checksum += byte;
Alex Young 14:155f9a55ec51 214 parser->currentMessage.length = ((uint16_t)byte) << 8;
Alex Young 3:abc451d82b88 215 parser->state = XBPS_ExtendedLengthLsb;
Alex Young 3:abc451d82b88 216 break;
Alex Young 3:abc451d82b88 217
Alex Young 3:abc451d82b88 218 case XBPS_ExtendedLengthLsb:
Alex Young 3:abc451d82b88 219 parser->checksum += byte;
Alex Young 14:155f9a55ec51 220 parser->currentMessage.length |= byte;
Alex Young 3:abc451d82b88 221 prepareForPayload(parser);
Alex Young 3:abc451d82b88 222 parser->state = XBPS_Payload;
Alex Young 3:abc451d82b88 223 break;
Alex Young 3:abc451d82b88 224
Alex Young 3:abc451d82b88 225 case XBPS_Payload:
Alex Young 3:abc451d82b88 226 parser->checksum += byte;
Alex Young 14:155f9a55ec51 227 if (parser->currentMessage.data)
Alex Young 3:abc451d82b88 228 {
Alex Young 19:46e88d37ecef 229 ((uint8_t*)parser->currentMessage.data)[parser->payloadReceived] = byte;
Alex Young 3:abc451d82b88 230 }
Alex Young 14:155f9a55ec51 231 if (++parser->payloadReceived == parser->currentMessage.length)
Alex Young 3:abc451d82b88 232 {
Alex Young 3:abc451d82b88 233 parser->state = XBPS_Checksum;
Alex Young 3:abc451d82b88 234 }
Alex Young 3:abc451d82b88 235 break;
Alex Young 3:abc451d82b88 236
Alex Young 3:abc451d82b88 237 case XBPS_Checksum:
Alex Young 3:abc451d82b88 238 parser->checksum += byte;
Alex Young 17:680f28e00d17 239 if ((parser->checksum == 0) &&
Alex Young 17:680f28e00d17 240 ((parser->currentMessage.length == 0) ||
Alex Young 17:680f28e00d17 241 parser->currentMessage.data))
Alex Young 3:abc451d82b88 242 {
Alex Young 19:46e88d37ecef 243 parseMessagePayload(parser);
Alex Young 14:155f9a55ec51 244 parser->callbacks.handleMessage(&parser->currentMessage);
Alex Young 3:abc451d82b88 245 }
Alex Young 3:abc451d82b88 246 parser->state = XBPS_Preamble;
Alex Young 3:abc451d82b88 247 break;
Alex Young 3:abc451d82b88 248 }
Alex Young 3:abc451d82b88 249 }
Alex Young 3:abc451d82b88 250
Alex Young 3:abc451d82b88 251 void XbusParser_parseBuffer(struct XbusParser* parser, uint8_t const* buf, size_t bufSize)
Alex Young 3:abc451d82b88 252 {
Alex Young 3:abc451d82b88 253 for (size_t i = 0; i < bufSize; ++i)
Alex Young 3:abc451d82b88 254 {
Alex Young 3:abc451d82b88 255 XbusParser_parseByte(parser, buf[i]);
Alex Young 3:abc451d82b88 256 }
Alex Young 3:abc451d82b88 257 }
Alex Young 3:abc451d82b88 258