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@2:d3d61d9d323e, 2014-04-27 (annotated)

Committer:
chrta
Date:
Sun Apr 27 14:50:13 2014 +0000
Revision:
2:d3d61d9d323e
Parent:
0:6b1f6139fb25
Child:
3:eb807d330292
Hardware is working

Who changed what in which revision?

UserRevisionLine numberNew contents of line
chrta 0:6b1f6139fb25 1 #include "IsoTpHandler.h"
chrta 2:d3d61d9d323e 2 #include "MODSERIAL.h"
chrta 2:d3d61d9d323e 3 extern MODSERIAL pc;
chrta 0:6b1f6139fb25 4
chrta 0:6b1f6139fb25 5 enum IsoTpMessageType
chrta 0:6b1f6139fb25 6 {
chrta 0:6b1f6139fb25 7 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 8 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 9 CONSECUTIVE_FRAME = 2, ///< A frame containing subsequent data for a multi-frame packet
chrta 0:6b1f6139fb25 10 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 11 };
chrta 0:6b1f6139fb25 12
chrta 0:6b1f6139fb25 13 enum IsoTpFlowType
chrta 0:6b1f6139fb25 14 {
chrta 0:6b1f6139fb25 15 CLEAR_TO_SEND = 0,
chrta 0:6b1f6139fb25 16 WAIT = 1,
chrta 0:6b1f6139fb25 17 OVERFLOW_ABORT = 2,
chrta 0:6b1f6139fb25 18 };
chrta 0:6b1f6139fb25 19
chrta 0:6b1f6139fb25 20 const IsoTpHandler::IdleState IsoTpHandler::idleState;
chrta 0:6b1f6139fb25 21 const IsoTpHandler::ConsequtiveTransferState IsoTpHandler::consequtiveTransferState;
chrta 0:6b1f6139fb25 22
chrta 0:6b1f6139fb25 23 IsoTpHandler::IdleState::IdleState()
chrta 0:6b1f6139fb25 24 {
chrta 0:6b1f6139fb25 25 }
chrta 0:6b1f6139fb25 26
chrta 0:6b1f6139fb25 27 void IsoTpHandler::IdleState::processInput(const CANMessage* message, IsoTpHandler* context) const
chrta 0:6b1f6139fb25 28 {
chrta 0:6b1f6139fb25 29 if (!IsoTpHandler::isValidIsoTpPacket(message))
chrta 0:6b1f6139fb25 30 {
chrta 0:6b1f6139fb25 31 return;
chrta 0:6b1f6139fb25 32 }
chrta 0:6b1f6139fb25 33 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 34 if (messageType == SINGLE_FRAME)
chrta 0:6b1f6139fb25 35 {
chrta 0:6b1f6139fb25 36 uint8_t messageSize = message->data[0] & 0x0F;
chrta 0:6b1f6139fb25 37 if (messageSize > message->len - 1)
chrta 0:6b1f6139fb25 38 {
chrta 2:d3d61d9d323e 39 pc.printf("Iso tp message is too short: iso len %d vs can len %d\r\n", messageSize, message->len);
chrta 0:6b1f6139fb25 40 return;
chrta 0:6b1f6139fb25 41 }
chrta 0:6b1f6139fb25 42 context->handle_decoded_packet(&message->data[1], messageSize);
chrta 0:6b1f6139fb25 43 return;
chrta 0:6b1f6139fb25 44 }
chrta 0:6b1f6139fb25 45 if (messageType == FIRST_FRAME)
chrta 0:6b1f6139fb25 46 {
chrta 0:6b1f6139fb25 47 if (message->len != 8)
chrta 0:6b1f6139fb25 48 {
chrta 2:d3d61d9d323e 49 pc.printf("Invalid iso tp message length for FIRST_FRAME, length is %d\r\n", message->len);
chrta 0:6b1f6139fb25 50 return;
chrta 0:6b1f6139fb25 51 }
chrta 0:6b1f6139fb25 52
chrta 0:6b1f6139fb25 53 uint16_t messageSize = ((message->data[0] & 0x0F) << 8) | (message->data[1]);
chrta 0:6b1f6139fb25 54 context->init_consequtive_reading(messageSize, &message->data[2]);
chrta 0:6b1f6139fb25 55 context->setState(&consequtiveTransferState);
chrta 0:6b1f6139fb25 56 return;
chrta 0:6b1f6139fb25 57 }
chrta 0:6b1f6139fb25 58 if (messageType == CONSECUTIVE_FRAME)
chrta 0:6b1f6139fb25 59 {
chrta 2:d3d61d9d323e 60 pc.printf("Invalid iso tp message in idle state, because unexpected CONSECUTIVE_FRAME received\r\n");
chrta 0:6b1f6139fb25 61 return;
chrta 0:6b1f6139fb25 62 }
chrta 0:6b1f6139fb25 63 if (messageType == FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 64 {
chrta 2:d3d61d9d323e 65 pc.printf("Invalid iso tp message, because unexpected FLOW_CONTOL_FRAME received\r\n");
chrta 0:6b1f6139fb25 66 return;
chrta 0:6b1f6139fb25 67 }
chrta 0:6b1f6139fb25 68
chrta 2:d3d61d9d323e 69 pc.printf("Invalid iso tp message ?!\r\n");
chrta 0:6b1f6139fb25 70 }
chrta 0:6b1f6139fb25 71
chrta 0:6b1f6139fb25 72 void IsoTpHandler::IdleState::onEnter(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 73 {
chrta 0:6b1f6139fb25 74 }
chrta 0:6b1f6139fb25 75
chrta 0:6b1f6139fb25 76 void IsoTpHandler::IdleState::onLeave(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 77 {
chrta 0:6b1f6139fb25 78 }
chrta 0:6b1f6139fb25 79
chrta 0:6b1f6139fb25 80 IsoTpHandler::ConsequtiveTransferState::ConsequtiveTransferState()
chrta 0:6b1f6139fb25 81 {
chrta 0:6b1f6139fb25 82 }
chrta 0:6b1f6139fb25 83
chrta 0:6b1f6139fb25 84 void IsoTpHandler::ConsequtiveTransferState::processInput(const CANMessage* message, IsoTpHandler* context) const
chrta 0:6b1f6139fb25 85 {
chrta 0:6b1f6139fb25 86 if (!IsoTpHandler::isValidIsoTpPacket(message))
chrta 0:6b1f6139fb25 87 {
chrta 0:6b1f6139fb25 88 return;
chrta 0:6b1f6139fb25 89 }
chrta 0:6b1f6139fb25 90 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 91 if (messageType == SINGLE_FRAME)
chrta 0:6b1f6139fb25 92 {
chrta 2:d3d61d9d323e 93 pc.printf("Received SINGLE_FRAME, expected consequitve frame\r\n");
chrta 0:6b1f6139fb25 94 return;
chrta 0:6b1f6139fb25 95 }
chrta 0:6b1f6139fb25 96 if (messageType == FIRST_FRAME)
chrta 0:6b1f6139fb25 97 {
chrta 2:d3d61d9d323e 98 pc.printf("Received FIRST_FRAME, expected consequitve frame\r\n");
chrta 0:6b1f6139fb25 99 return;
chrta 0:6b1f6139fb25 100 }
chrta 0:6b1f6139fb25 101 if (messageType == CONSECUTIVE_FRAME)
chrta 0:6b1f6139fb25 102 {
chrta 0:6b1f6139fb25 103 uint8_t index = message->data[0] & 0x0F;
chrta 0:6b1f6139fb25 104 if (index != context->getExpectedIndex())
chrta 0:6b1f6139fb25 105 {
chrta 2:d3d61d9d323e 106 pc.printf("In consequiive frame, received index %d, expected %d\r\n", index, context->getExpectedIndex());
chrta 0:6b1f6139fb25 107 context->setState(&IsoTpHandler::idleState);
chrta 0:6b1f6139fb25 108 return;
chrta 0:6b1f6139fb25 109
chrta 0:6b1f6139fb25 110 }
chrta 0:6b1f6139fb25 111
chrta 0:6b1f6139fb25 112 if (context->appendReceivedData(&message->data[1], message->len - 1))
chrta 0:6b1f6139fb25 113 {
chrta 2:d3d61d9d323e 114 pc.printf("In consequtive frame, change state\r\n");
chrta 0:6b1f6139fb25 115
chrta 0:6b1f6139fb25 116 context->setState(&IsoTpHandler::idleState);
chrta 0:6b1f6139fb25 117 }
chrta 2:d3d61d9d323e 118 context->incrementExpectedIndex();
chrta 0:6b1f6139fb25 119 return;
chrta 0:6b1f6139fb25 120 }
chrta 0:6b1f6139fb25 121 if (messageType == FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 122 {
chrta 2:d3d61d9d323e 123 pc.printf("Received FLOW_CONTROL_FRAME, expected consequitve frame\r\n");
chrta 0:6b1f6139fb25 124 return;
chrta 0:6b1f6139fb25 125 }
chrta 0:6b1f6139fb25 126
chrta 2:d3d61d9d323e 127 pc.printf("Invalid iso tp message, expected consequitve frame ?!\r\n");
chrta 0:6b1f6139fb25 128 }
chrta 0:6b1f6139fb25 129
chrta 0:6b1f6139fb25 130 void IsoTpHandler::ConsequtiveTransferState::onEnter(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 131 {
chrta 0:6b1f6139fb25 132 }
chrta 0:6b1f6139fb25 133
chrta 0:6b1f6139fb25 134 void IsoTpHandler::ConsequtiveTransferState::onLeave(IsoTpHandler* context) const
chrta 0:6b1f6139fb25 135 {
chrta 0:6b1f6139fb25 136 }
chrta 0:6b1f6139fb25 137
chrta 0:6b1f6139fb25 138 IsoTpHandler::IsoTpHandler(CAN* canInterface)
chrta 0:6b1f6139fb25 139 : m_state(&idleState)
chrta 0:6b1f6139fb25 140 , m_canInterface (canInterface)
chrta 0:6b1f6139fb25 141 {
chrta 0:6b1f6139fb25 142 m_state->onEnter(this);
chrta 0:6b1f6139fb25 143 }
chrta 0:6b1f6139fb25 144
chrta 0:6b1f6139fb25 145 void IsoTpHandler::processCanMessage(const CANMessage* message)
chrta 0:6b1f6139fb25 146 {
chrta 2:d3d61d9d323e 147 pc.printf("Received new CAN message:\r\n");
chrta 2:d3d61d9d323e 148 pc.printf(" ID: 0x%X\r\n", message->id);
chrta 2:d3d61d9d323e 149 pc.printf(" Len: %d\r\n", message->len);
chrta 2:d3d61d9d323e 150 pc.printf(" Type: %s\r\n", (message->type == CANData ? "data" : "remote"));
chrta 2:d3d61d9d323e 151 pc.printf(" Format: %s\r\n", (message->format == CANStandard ? "standard" : "extended"));
chrta 2:d3d61d9d323e 152 pc.printf( "Data: ");
chrta 0:6b1f6139fb25 153 if (message->len > 8) {
chrta 0:6b1f6139fb25 154 //paranoia
chrta 0:6b1f6139fb25 155 error(" WRONG DATA LEN! ");
chrta 0:6b1f6139fb25 156 return;
chrta 0:6b1f6139fb25 157 }
chrta 0:6b1f6139fb25 158 for (unsigned int i = 0; i < message->len; ++i) {
chrta 2:d3d61d9d323e 159 pc.printf("%X ", message->data[i]);
chrta 0:6b1f6139fb25 160 }
chrta 2:d3d61d9d323e 161 pc.printf("\r\n");
chrta 0:6b1f6139fb25 162 m_state->processInput(message, this);
chrta 0:6b1f6139fb25 163 }
chrta 0:6b1f6139fb25 164
chrta 0:6b1f6139fb25 165 void IsoTpHandler::handle_decoded_packet(const uint8_t* data, uint16_t length)
chrta 0:6b1f6139fb25 166 {
chrta 0:6b1f6139fb25 167 //todo write into mailbox so another thread can consume this or directly call a callback
chrta 2:d3d61d9d323e 168 pc.printf("New decoded packet: Length: %d\r\n", length);
chrta 2:d3d61d9d323e 169 pc.printf(" Data: ");
chrta 0:6b1f6139fb25 170 for (uint16_t i = 0; i < length; ++i)
chrta 0:6b1f6139fb25 171 {
chrta 2:d3d61d9d323e 172 pc.printf("%X ", data[i]);
chrta 0:6b1f6139fb25 173 }
chrta 2:d3d61d9d323e 174 pc.printf("\r\n");
chrta 0:6b1f6139fb25 175 }
chrta 0:6b1f6139fb25 176
chrta 0:6b1f6139fb25 177 void IsoTpHandler::init_consequtive_reading(uint16_t messageSize, const uint8_t* data)
chrta 0:6b1f6139fb25 178 {
chrta 0:6b1f6139fb25 179 char msgContent[8];
chrta 0:6b1f6139fb25 180 msgContent[0] = (FLOW_CONTOL_FRAME << 4) | CLEAR_TO_SEND;
chrta 0:6b1f6139fb25 181 msgContent[1] = 0; //remaining frames should to be sent without flow control or delay
chrta 0:6b1f6139fb25 182 msgContent[2] = 0; //Separation Time (ST), minimum delay time between frames (end of one frame and the beginning of the other)
chrta 0:6b1f6139fb25 183 //<= 127, separation time in milliseconds.
chrta 0:6b1f6139fb25 184 //0xF1 to 0xF9, 100 to 900 microseconds.
chrta 0:6b1f6139fb25 185 msgContent[3] = 0;
chrta 0:6b1f6139fb25 186 msgContent[4] = 0;
chrta 0:6b1f6139fb25 187 msgContent[5] = 0;
chrta 0:6b1f6139fb25 188 msgContent[6] = 0;
chrta 0:6b1f6139fb25 189 msgContent[7] = 0;
chrta 2:d3d61d9d323e 190 m_canInterface->write(CANMessage(0x7E0, msgContent, sizeof(msgContent))); //or 7DF?
chrta 0:6b1f6139fb25 191
chrta 0:6b1f6139fb25 192 memcpy(m_messageBuffer, data, 6);
chrta 0:6b1f6139fb25 193 m_expectedMessageSize = messageSize;
chrta 0:6b1f6139fb25 194 m_currentMessageSize = 6;
chrta 0:6b1f6139fb25 195 m_expectedIndex = 1;
chrta 0:6b1f6139fb25 196 }
chrta 0:6b1f6139fb25 197
chrta 0:6b1f6139fb25 198 void IsoTpHandler::setState(const State* state)
chrta 0:6b1f6139fb25 199 {
chrta 0:6b1f6139fb25 200 if (state == m_state)
chrta 0:6b1f6139fb25 201 {
chrta 0:6b1f6139fb25 202 return;
chrta 0:6b1f6139fb25 203 }
chrta 0:6b1f6139fb25 204
chrta 0:6b1f6139fb25 205 m_state->onLeave(this);
chrta 0:6b1f6139fb25 206 m_state = state;
chrta 0:6b1f6139fb25 207 m_state->onEnter(this);
chrta 0:6b1f6139fb25 208 }
chrta 0:6b1f6139fb25 209
chrta 0:6b1f6139fb25 210 bool IsoTpHandler::isValidIsoTpPacket(const CANMessage* message)
chrta 0:6b1f6139fb25 211 {
chrta 0:6b1f6139fb25 212 if (message->len < 1)
chrta 0:6b1f6139fb25 213 {
chrta 2:d3d61d9d323e 214 pc.printf("Invalid iso tp message, length is zero\r\n");
chrta 0:6b1f6139fb25 215 return false;
chrta 0:6b1f6139fb25 216 }
chrta 0:6b1f6139fb25 217 uint8_t messageType = message->data[0] >> 4;
chrta 0:6b1f6139fb25 218 if (messageType > FLOW_CONTOL_FRAME)
chrta 0:6b1f6139fb25 219 {
chrta 2:d3d61d9d323e 220 pc.printf("Invalid iso tp message type %d\r\n", messageType);
chrta 0:6b1f6139fb25 221 return false;
chrta 0:6b1f6139fb25 222 }
chrta 0:6b1f6139fb25 223 return true;
chrta 0:6b1f6139fb25 224 }
chrta 0:6b1f6139fb25 225
chrta 0:6b1f6139fb25 226 uint8_t IsoTpHandler::getExpectedIndex() const
chrta 0:6b1f6139fb25 227 {
chrta 0:6b1f6139fb25 228 return m_expectedIndex;
chrta 0:6b1f6139fb25 229 }
chrta 0:6b1f6139fb25 230
chrta 0:6b1f6139fb25 231 void IsoTpHandler::incrementExpectedIndex()
chrta 0:6b1f6139fb25 232 {
chrta 0:6b1f6139fb25 233 ++m_expectedIndex;
chrta 0:6b1f6139fb25 234 if (m_expectedIndex >= 16)
chrta 0:6b1f6139fb25 235 {
chrta 0:6b1f6139fb25 236 m_expectedIndex = 0;
chrta 0:6b1f6139fb25 237 }
chrta 0:6b1f6139fb25 238 }
chrta 0:6b1f6139fb25 239
chrta 0:6b1f6139fb25 240 bool IsoTpHandler::appendReceivedData(const uint8_t* data, uint8_t length)
chrta 0:6b1f6139fb25 241 {
chrta 0:6b1f6139fb25 242 if (sizeof(m_messageBuffer) < m_currentMessageSize + length)
chrta 0:6b1f6139fb25 243 {
chrta 2:d3d61d9d323e 244 pc.printf("Buffer in appendReceivedData too small, already got %d bytes, new %d bytes, expected %d bytes.\r\n", m_currentMessageSize, length, m_expectedMessageSize);
chrta 0:6b1f6139fb25 245 return true; //switch state
chrta 0:6b1f6139fb25 246 }
chrta 0:6b1f6139fb25 247
chrta 0:6b1f6139fb25 248 if (m_expectedMessageSize < m_currentMessageSize + length)
chrta 0:6b1f6139fb25 249 {
chrta 2:d3d61d9d323e 250 pc.printf("Got too much data in appendReceivedData, already got %d bytes, new %d bytes, expected %d bytes.\r\n", m_currentMessageSize, length, m_expectedMessageSize);
chrta 0:6b1f6139fb25 251 length = m_expectedMessageSize - m_currentMessageSize;
chrta 0:6b1f6139fb25 252 }
chrta 0:6b1f6139fb25 253
chrta 0:6b1f6139fb25 254 memcpy(m_messageBuffer + m_currentMessageSize, data, length);
chrta 0:6b1f6139fb25 255 m_currentMessageSize += length;
chrta 0:6b1f6139fb25 256
chrta 0:6b1f6139fb25 257 if (m_expectedMessageSize == m_currentMessageSize)
chrta 0:6b1f6139fb25 258 {
chrta 0:6b1f6139fb25 259 handle_decoded_packet(m_messageBuffer, m_expectedMessageSize);
chrta 0:6b1f6139fb25 260 return true; //switch state
chrta 0:6b1f6139fb25 261 }
chrta 0:6b1f6139fb25 262
chrta 0:6b1f6139fb25 263 return false; //do not switch state
chrta 0:6b1f6139fb25 264 }