Christian Taedcke / Mbed 2 deprecated ObdDisplay

Small project to display some OBD values from the Toyota GT86/ Subaru BRZ/ Scion FRS on an OLED display.

Dependencies:   Adafruit_GFX MODSERIAL mbed-rtos mbed

IsoTpHandler.cpp@0:6b1f6139fb25, 2014-04-22 (annotated)

Committer:
chrta
Date:
Tue Apr 22 14:51:04 2014 +0000
Revision:
0:6b1f6139fb25
Child:
2:d3d61d9d323e
Initial checkin

Who changed what in which revision?

UserRevisionLine numberNew contents of line
chrta 0:6b1f6139fb25 1 #include "IsoTpHandler.h"
chrta 0:6b1f6139fb25 2
chrta 0:6b1f6139fb25 3 enum IsoTpMessageType
chrta 0:6b1f6139fb25 4 {
chrta 0:6b1f6139fb25 5 SINGLE_FRAME = 0, ///< The single frame transferred contains the complete payload of up to 7 bytes (normal addressing) or 6 bytes (extended addressing)
chrta 0:6b1f6139fb25 6 FIRST_FRAME = 1, ///< The first frame of a longer multi-frame message packet, used when more than 6/7 bytes of data segmented must be communicated. The first frame contains the length of the full packet, along with the initial data.
chrta 0:6b1f6139fb25 7 CONSECUTIVE_FRAME = 2, ///< A frame containing subsequent data for a multi-frame packet
chrta 0:6b1f6139fb25 8 FLOW_CONTOL_FRAME = 3, ///< The response from the receiver, acknowledging a First-frame segment. It lays down the parameters for the transmission of further consecutive frames.
chrta 0:6b1f6139fb25 9 };
chrta 0:6b1f6139fb25 10
chrta 0:6b1f6139fb25 11 enum IsoTpFlowType
chrta 0:6b1f6139fb25 12 {
chrta 0:6b1f6139fb25 13 CLEAR_TO_SEND = 0,
chrta 0:6b1f6139fb25 14 WAIT = 1,
chrta 0:6b1f6139fb25 15 OVERFLOW_ABORT = 2,
chrta 0:6b1f6139fb25 16 };
chrta 0:6b1f6139fb25 17
chrta 0:6b1f6139fb25 18 const IsoTpHandler::IdleState IsoTpHandler::idleState;
chrta 0:6b1f6139fb25 19 const IsoTpHandler::ConsequtiveTransferState IsoTpHandler::consequtiveTransferState;
chrta 0:6b1f6139fb25 20
chrta 0:6b1f6139fb25 21 IsoTpHandler::IdleState::IdleState()
chrta 0:6b1f6139fb25 22 {
chrta 0:6b1f6139fb25 23 }
chrta 0:6b1f6139fb25 24
chrta 0:6b1f6139fb25 25 void IsoTpHandler::IdleState::processInput(const CANMessage* message, IsoTpHandler* context) const
chrta 0:6b1f6139fb25 26 {
chrta 0:6b1f6139fb25 27 if (!IsoTpHandler::isValidIsoTpPacket(message))
chrta 0:6b1f6139fb25 28 {
chrta 0:6b1f6139fb25 29 return;
chrta 0:6b1f6139fb25 30 }
chrta 0:6b1f6139fb25 31 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 32 if (messageType == SINGLE_FRAME)
chrta 0:6b1f6139fb25 33 {
chrta 0:6b1f6139fb25 34 uint8_t messageSize = message->data[0] & 0x0F;
chrta 0:6b1f6139fb25 35 if (messageSize > message->len - 1)
chrta 0:6b1f6139fb25 36 {
chrta 0:6b1f6139fb25 37 printf("Iso tp message is too short: iso len %d vs can len %d\n", messageSize, message->len);
chrta 0:6b1f6139fb25 38 return;
chrta 0:6b1f6139fb25 39 }
chrta 0:6b1f6139fb25 40 context->handle_decoded_packet(&message->data[1], messageSize);
chrta 0:6b1f6139fb25 41 return;
chrta 0:6b1f6139fb25 42 }
chrta 0:6b1f6139fb25 43 if (messageType == FIRST_FRAME)
chrta 0:6b1f6139fb25 44 {
chrta 0:6b1f6139fb25 45 if (message->len != 8)
chrta 0:6b1f6139fb25 46 {
chrta 0:6b1f6139fb25 47 printf("Invalid iso tp message length for FIRST_FRAME, length is %d\n", message->len);
chrta 0:6b1f6139fb25 48 return;
chrta 0:6b1f6139fb25 49 }
chrta 0:6b1f6139fb25 50
chrta 0:6b1f6139fb25 51 uint16_t messageSize = ((message->data[0] & 0x0F) << 8) | (message->data[1]);
chrta 0:6b1f6139fb25 52 context->init_consequtive_reading(messageSize, &message->data[2]);
chrta 0:6b1f6139fb25 53 context->setState(&consequtiveTransferState);
chrta 0:6b1f6139fb25 54 return;
chrta 0:6b1f6139fb25 55 }
chrta 0:6b1f6139fb25 56 if (messageType == CONSECUTIVE_FRAME)
chrta 0:6b1f6139fb25 57 {
chrta 0:6b1f6139fb25 58 printf("Invalid iso tp message in idle state, because unexpected CONSECUTIVE_FRAME received\n");
chrta 0:6b1f6139fb25 59 return;
chrta 0:6b1f6139fb25 60 }
chrta 0:6b1f6139fb25 61 if (messageType == FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 62 {
chrta 0:6b1f6139fb25 63 printf("Invalid iso tp message, because unexpected FLOW_CONTOL_FRAME received\n");
chrta 0:6b1f6139fb25 64 return;
chrta 0:6b1f6139fb25 65 }
chrta 0:6b1f6139fb25 66
chrta 0:6b1f6139fb25 67 printf("Invalid iso tp message ?!\n");
chrta 0:6b1f6139fb25 68 }
chrta 0:6b1f6139fb25 69
chrta 0:6b1f6139fb25 70 void IsoTpHandler::IdleState::onEnter(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 71 {
chrta 0:6b1f6139fb25 72 }
chrta 0:6b1f6139fb25 73
chrta 0:6b1f6139fb25 74 void IsoTpHandler::IdleState::onLeave(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 75 {
chrta 0:6b1f6139fb25 76 }
chrta 0:6b1f6139fb25 77
chrta 0:6b1f6139fb25 78 IsoTpHandler::ConsequtiveTransferState::ConsequtiveTransferState()
chrta 0:6b1f6139fb25 79 {
chrta 0:6b1f6139fb25 80 }
chrta 0:6b1f6139fb25 81
chrta 0:6b1f6139fb25 82 void IsoTpHandler::ConsequtiveTransferState::processInput(const CANMessage* message, IsoTpHandler* context) const
chrta 0:6b1f6139fb25 83 {
chrta 0:6b1f6139fb25 84 if (!IsoTpHandler::isValidIsoTpPacket(message))
chrta 0:6b1f6139fb25 85 {
chrta 0:6b1f6139fb25 86 return;
chrta 0:6b1f6139fb25 87 }
chrta 0:6b1f6139fb25 88 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 89 if (messageType == SINGLE_FRAME)
chrta 0:6b1f6139fb25 90 {
chrta 0:6b1f6139fb25 91 printf("Received SINGLE_FRAME, expected consequitve frame\n");
chrta 0:6b1f6139fb25 92 return;
chrta 0:6b1f6139fb25 93 }
chrta 0:6b1f6139fb25 94 if (messageType == FIRST_FRAME)
chrta 0:6b1f6139fb25 95 {
chrta 0:6b1f6139fb25 96 printf("Received FIRST_FRAME, expected consequitve frame\n");
chrta 0:6b1f6139fb25 97 return;
chrta 0:6b1f6139fb25 98 }
chrta 0:6b1f6139fb25 99 if (messageType == CONSECUTIVE_FRAME)
chrta 0:6b1f6139fb25 100 {
chrta 0:6b1f6139fb25 101 uint8_t index = message->data[0] & 0x0F;
chrta 0:6b1f6139fb25 102 if (index != context->getExpectedIndex())
chrta 0:6b1f6139fb25 103 {
chrta 0:6b1f6139fb25 104 printf("In consequiive frame, received index %d, expected %d\n", index, context->getExpectedIndex());
chrta 0:6b1f6139fb25 105 context->setState(&IsoTpHandler::idleState);
chrta 0:6b1f6139fb25 106 return;
chrta 0:6b1f6139fb25 107
chrta 0:6b1f6139fb25 108 }
chrta 0:6b1f6139fb25 109
chrta 0:6b1f6139fb25 110 if (context->appendReceivedData(&message->data[1], message->len - 1))
chrta 0:6b1f6139fb25 111 {
chrta 0:6b1f6139fb25 112 printf("In consequtive frame, change state\n");
chrta 0:6b1f6139fb25 113
chrta 0:6b1f6139fb25 114 context->setState(&IsoTpHandler::idleState);
chrta 0:6b1f6139fb25 115 }
chrta 0:6b1f6139fb25 116 return;
chrta 0:6b1f6139fb25 117 }
chrta 0:6b1f6139fb25 118 if (messageType == FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 119 {
chrta 0:6b1f6139fb25 120 printf("Received FLOW_CONTROL_FRAME, expected consequitve frame\n");
chrta 0:6b1f6139fb25 121 return;
chrta 0:6b1f6139fb25 122 }
chrta 0:6b1f6139fb25 123
chrta 0:6b1f6139fb25 124 printf("Invalid iso tp message, expected consequitve frame ?!\n");
chrta 0:6b1f6139fb25 125 }
chrta 0:6b1f6139fb25 126
chrta 0:6b1f6139fb25 127 void IsoTpHandler::ConsequtiveTransferState::onEnter(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 128 {
chrta 0:6b1f6139fb25 129 }
chrta 0:6b1f6139fb25 130
chrta 0:6b1f6139fb25 131 void IsoTpHandler::ConsequtiveTransferState::onLeave(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 132 {
chrta 0:6b1f6139fb25 133 }
chrta 0:6b1f6139fb25 134
chrta 0:6b1f6139fb25 135 IsoTpHandler::IsoTpHandler(CAN* canInterface)
chrta 0:6b1f6139fb25 136 : m_state(&idleState)
chrta 0:6b1f6139fb25 137 , m_canInterface (canInterface)
chrta 0:6b1f6139fb25 138 {
chrta 0:6b1f6139fb25 139 m_state->onEnter(this);
chrta 0:6b1f6139fb25 140 }
chrta 0:6b1f6139fb25 141
chrta 0:6b1f6139fb25 142 void IsoTpHandler::processCanMessage(const CANMessage* message)
chrta 0:6b1f6139fb25 143 {
chrta 0:6b1f6139fb25 144 printf("Received new CAN message:\n");
chrta 0:6b1f6139fb25 145 printf(" ID: 0x%X\n", message->id);
chrta 0:6b1f6139fb25 146 printf(" Len: %d\n", message->len);
chrta 0:6b1f6139fb25 147 printf(" Type: %s\n", (message->type == CANData ? "data" : "remote"));
chrta 0:6b1f6139fb25 148 printf(" Format: %s\n", (message->format == CANStandard ? "standard" : "extended"));
chrta 0:6b1f6139fb25 149 printf( "Data: ");
chrta 0:6b1f6139fb25 150 if (message->len > 8) {
chrta 0:6b1f6139fb25 151 //paranoia
chrta 0:6b1f6139fb25 152 error(" WRONG DATA LEN! ");
chrta 0:6b1f6139fb25 153 return;
chrta 0:6b1f6139fb25 154 }
chrta 0:6b1f6139fb25 155 for (unsigned int i = 0; i < message->len; ++i) {
chrta 0:6b1f6139fb25 156 printf("%X ", message->data[i]);
chrta 0:6b1f6139fb25 157 }
chrta 0:6b1f6139fb25 158 printf("\n");
chrta 0:6b1f6139fb25 159 m_state->processInput(message, this);
chrta 0:6b1f6139fb25 160 }
chrta 0:6b1f6139fb25 161
chrta 0:6b1f6139fb25 162 void IsoTpHandler::handle_decoded_packet(const uint8_t* data, uint16_t length)
chrta 0:6b1f6139fb25 163 {
chrta 0:6b1f6139fb25 164 //todo write into mailbox so another thread can consume this or directly call a callback
chrta 0:6b1f6139fb25 165 printf("New decoded packet: Length: %d\n", length);
chrta 0:6b1f6139fb25 166 printf(" Data: ");
chrta 0:6b1f6139fb25 167 for (uint16_t i = 0; i < length; ++i)
chrta 0:6b1f6139fb25 168 {
chrta 0:6b1f6139fb25 169 printf("%X ", data[i]);
chrta 0:6b1f6139fb25 170 }
chrta 0:6b1f6139fb25 171 printf("\n");
chrta 0:6b1f6139fb25 172 }
chrta 0:6b1f6139fb25 173
chrta 0:6b1f6139fb25 174 void IsoTpHandler::init_consequtive_reading(uint16_t messageSize, const uint8_t* data)
chrta 0:6b1f6139fb25 175 {
chrta 0:6b1f6139fb25 176 char msgContent[8];
chrta 0:6b1f6139fb25 177 msgContent[0] = (FLOW_CONTOL_FRAME << 4) | CLEAR_TO_SEND;
chrta 0:6b1f6139fb25 178 msgContent[1] = 0; //remaining frames should to be sent without flow control or delay
chrta 0:6b1f6139fb25 179 msgContent[2] = 0; //Separation Time (ST), minimum delay time between frames (end of one frame and the beginning of the other)
chrta 0:6b1f6139fb25 180 //<= 127, separation time in milliseconds.
chrta 0:6b1f6139fb25 181 //0xF1 to 0xF9, 100 to 900 microseconds.
chrta 0:6b1f6139fb25 182 msgContent[3] = 0;
chrta 0:6b1f6139fb25 183 msgContent[4] = 0;
chrta 0:6b1f6139fb25 184 msgContent[5] = 0;
chrta 0:6b1f6139fb25 185 msgContent[6] = 0;
chrta 0:6b1f6139fb25 186 msgContent[7] = 0;
chrta 0:6b1f6139fb25 187 m_canInterface->write(CANMessage(0x7DF, msgContent, sizeof(msgContent)));
chrta 0:6b1f6139fb25 188
chrta 0:6b1f6139fb25 189 memcpy(m_messageBuffer, data, 6);
chrta 0:6b1f6139fb25 190 m_expectedMessageSize = messageSize;
chrta 0:6b1f6139fb25 191 m_currentMessageSize = 6;
chrta 0:6b1f6139fb25 192 m_expectedIndex = 1;
chrta 0:6b1f6139fb25 193 }
chrta 0:6b1f6139fb25 194
chrta 0:6b1f6139fb25 195 void IsoTpHandler::setState(const State* state)
chrta 0:6b1f6139fb25 196 {
chrta 0:6b1f6139fb25 197 if (state == m_state)
chrta 0:6b1f6139fb25 198 {
chrta 0:6b1f6139fb25 199 return;
chrta 0:6b1f6139fb25 200 }
chrta 0:6b1f6139fb25 201
chrta 0:6b1f6139fb25 202 m_state->onLeave(this);
chrta 0:6b1f6139fb25 203 m_state = state;
chrta 0:6b1f6139fb25 204 m_state->onEnter(this);
chrta 0:6b1f6139fb25 205 }
chrta 0:6b1f6139fb25 206
chrta 0:6b1f6139fb25 207 bool IsoTpHandler::isValidIsoTpPacket(const CANMessage* message)
chrta 0:6b1f6139fb25 208 {
chrta 0:6b1f6139fb25 209 if (message->len < 1)
chrta 0:6b1f6139fb25 210 {
chrta 0:6b1f6139fb25 211 printf("Invalid iso tp message, length is zero\n");
chrta 0:6b1f6139fb25 212 return false;
chrta 0:6b1f6139fb25 213 }
chrta 0:6b1f6139fb25 214 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 215 if (messageType > FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 216 {
chrta 0:6b1f6139fb25 217 printf("Invalid iso tp message type %d\n", messageType);
chrta 0:6b1f6139fb25 218 return false;
chrta 0:6b1f6139fb25 219 }
chrta 0:6b1f6139fb25 220 return true;
chrta 0:6b1f6139fb25 221 }
chrta 0:6b1f6139fb25 222
chrta 0:6b1f6139fb25 223 uint8_t IsoTpHandler::getExpectedIndex() const
chrta 0:6b1f6139fb25 224 {
chrta 0:6b1f6139fb25 225 return m_expectedIndex;
chrta 0:6b1f6139fb25 226 }
chrta 0:6b1f6139fb25 227
chrta 0:6b1f6139fb25 228 void IsoTpHandler::incrementExpectedIndex()
chrta 0:6b1f6139fb25 229 {
chrta 0:6b1f6139fb25 230 ++m_expectedIndex;
chrta 0:6b1f6139fb25 231 if (m_expectedIndex >= 16)
chrta 0:6b1f6139fb25 232 {
chrta 0:6b1f6139fb25 233 m_expectedIndex = 0;
chrta 0:6b1f6139fb25 234 }
chrta 0:6b1f6139fb25 235 }
chrta 0:6b1f6139fb25 236
chrta 0:6b1f6139fb25 237 bool IsoTpHandler::appendReceivedData(const uint8_t* data, uint8_t length)
chrta 0:6b1f6139fb25 238 {
chrta 0:6b1f6139fb25 239 if (sizeof(m_messageBuffer) < m_currentMessageSize + length)
chrta 0:6b1f6139fb25 240 {
chrta 0:6b1f6139fb25 241 printf("Buffer in appendReceivedData too small, already got %d bytes, new %d bytes, expected %d bytes.\n", m_currentMessageSize, length, m_expectedMessageSize);
chrta 0:6b1f6139fb25 242 return true; //switch state
chrta 0:6b1f6139fb25 243 }
chrta 0:6b1f6139fb25 244
chrta 0:6b1f6139fb25 245 if (m_expectedMessageSize < m_currentMessageSize + length)
chrta 0:6b1f6139fb25 246 {
chrta 0:6b1f6139fb25 247 printf("Got too much data in appendReceivedData, already got %d bytes, new %d bytes, expected %d bytes.\n", m_currentMessageSize, length, m_expectedMessageSize);
chrta 0:6b1f6139fb25 248 length = m_expectedMessageSize - m_currentMessageSize;
chrta 0:6b1f6139fb25 249 }
chrta 0:6b1f6139fb25 250
chrta 0:6b1f6139fb25 251 memcpy(m_messageBuffer + m_currentMessageSize, data, length);
chrta 0:6b1f6139fb25 252 m_currentMessageSize += length;
chrta 0:6b1f6139fb25 253
chrta 0:6b1f6139fb25 254 if (m_expectedMessageSize == m_currentMessageSize)
chrta 0:6b1f6139fb25 255 {
chrta 0:6b1f6139fb25 256 handle_decoded_packet(m_messageBuffer, m_expectedMessageSize);
chrta 0:6b1f6139fb25 257 return true; //switch state
chrta 0:6b1f6139fb25 258 }
chrta 0:6b1f6139fb25 259
chrta 0:6b1f6139fb25 260 return false; //do not switch state
chrta 0:6b1f6139fb25 261 }