Jason Gaunt
Libraries to support working with GMLAN - General Motors CAN BUS network in most of their vehicles between 2007-present day. Please note this is a work in progress and not guaranteed to be correct, use at your own risk! Read commit logs / subscribe to see what has been added, it's a work in progress after all ;)
Revision 6:32592425aa57, committed 2013-04-03
- Comitter:
- foxdie
- Date:
- Wed Apr 03 16:09:10 2013 +0000
- Parent:
- 5:d0b067be6d44
- Child:
- 7:5ec65e6e8095
- Commit message:
- Added wrapper for 11-bit requests
Changed in this revision
--- a/GMLAN.cpp Tue Mar 19 10:03:21 2013 +0000
+++ b/GMLAN.cpp Wed Apr 03 16:09:10 2013 +0000
@@ -75,4 +75,98 @@
return CANMessage(hdr.encode29bit(), datatochars, data.size(), CANData, CANExtended);
else
return CANMessage(arbitration, datatochars, data.size(), CANData, CANStandard);
+}
+
+GMLAN_11Bit_Request::GMLAN_11Bit_Request(int _id, vector<char> _request) {
+ id = _id;
+ request_data = _request;
+ tx_bytes = rx_bytes = 0;
+ tx_frame_counter = rx_frame_counter = 1;
+ const char _fp [8] = {0xAA,0xAA,0xAA,0xAA,0xAA,0xAA,0xAA,0xAA};
+ memcpy(frame_padding, _fp, 8);
+ request_state = GMLAN_STATE_READY_TO_SEND;
+}
+CANMessage GMLAN_11Bit_Request::getNextFrame(void) {
+ char datatochars [8];
+ memcpy(datatochars, frame_padding, 8);
+
+ if (request_data.size() < 8) {
+ // Unsegmented frame
+ datatochars[0] = (GMLAN_PCI_UNSEGMENTED << 4) | (request_data.size() & 0xF);
+ for (int i = 0; i < request_data.size(); i++) datatochars[i+1] = request_data[i];
+ request_state = GMLAN_STATE_AWAITING_REPLY;
+ } else if (tx_bytes == 0) {
+ // First segmented frame
+ datatochars[0] = (GMLAN_PCI_SEGMENTED << 4) | ((request_data.size() >> 8) & 0xF);
+ datatochars[1] = request_data.size() & 0xFF;
+ for (int i = 0; i < 6; i++) {
+ datatochars[i+2] = request_data[i];
+ tx_bytes++;
+ }
+ request_state = GMLAN_STATE_AWAITING_FC;
+ } else if (tx_bytes <= request_data.size()) {
+ // Additional segmented frame with data left to transmit
+ datatochars[0] = (GMLAN_PCI_ADDITIONAL << 4) | (tx_frame_counter & 0xF);
+ int old_tx_bytes = tx_bytes;
+ for (int i = old_tx_bytes; i < old_tx_bytes + 7; i++) {
+ if (i >= request_data.size()) break;
+ datatochars[(i+1)-old_tx_bytes] = request_data[i];
+ tx_bytes++;
+ }
+ tx_frame_counter++;
+ if (tx_frame_counter > 0xF) tx_frame_counter = 0x0;
+ }
+
+ if (tx_bytes >= request_data.size()) request_state = GMLAN_STATE_AWAITING_REPLY;
+
+ return CANMessage(id, datatochars, 8, CANData, CANStandard);
+}
+CANMessage GMLAN_11Bit_Request::getFlowControl(void) {
+ request_state = GMLAN_STATE_AWAITING_REPLY;
+ GMLAN_Message buffer = GMLAN_Message(0x0, id, 0x0, 0x30, 0x0, 0x0);
+ return buffer.generate();
+}
+void GMLAN_11Bit_Request::processFrame(CANMessage msg) {
+ if (((msg.id & 0xFF) == (id & 0xFF)) && (request_state == GMLAN_STATE_AWAITING_REPLY)) {
+ // Only handle requests we've instigated
+ char datatochars [8];
+ memcpy(datatochars, msg.data, 8);
+
+ if (((datatochars[0] >> 4) & 0xF) == GMLAN_PCI_UNSEGMENTED) {
+ // Unsegmented frame
+ rx_bytes = datatochars[0] & 0xF;
+ if (datatochars[1] == GMLAN_SID_ERROR) {
+ // Error frame
+ if ((rx_bytes == 3) && (datatochars[3] == 0x78)) return; // "Still processing request" message, ignore this one
+ request_state = GMLAN_STATE_ERROR;
+ } else request_state = GMLAN_STATE_COMPLETED;
+ for (int i = 1; i < (rx_bytes+1); i++) response_data.push_back(datatochars[i]);
+ } else if (((datatochars[0] >> 4) & 0xF) == GMLAN_PCI_SEGMENTED) {
+ // First segmented frame
+ rx_bytes = datatochars[0] & 0xF;
+ rx_bytes = (rx_bytes << 8) | datatochars[1];
+ for (int i = 2; i < 8; i++) {
+ if ((i - 2) >= rx_bytes) {
+ // Safety net for incorrectly formatted packets
+ request_state = GMLAN_STATE_COMPLETED;
+ return;
+ }
+ response_data.push_back(datatochars[i]);
+ }
+ request_state = GMLAN_STATE_SEND_FC;
+ } else if (((datatochars[0] >> 4) & 0xF) == GMLAN_PCI_ADDITIONAL) {
+ // Additional segmented frame
+ // TODO check for frame order
+ for (int i = 1; i < 8; i++) {
+ if (response_data.size() + 1 >= rx_bytes) {
+ request_state = GMLAN_STATE_COMPLETED;
+ return;
+ }
+ response_data.push_back(datatochars[i]);
+ }
+ } else if (((datatochars[0] >> 4) & 0xF) == GMLAN_PCI_FLOW_CONTROL) {
+ // Flow control frame
+ request_state = GMLAN_STATE_SEND_DATA;
+ }
+ }
}
\ No newline at end of file
--- a/GMLAN.h Tue Mar 19 10:03:21 2013 +0000
+++ b/GMLAN.h Wed Apr 03 16:09:10 2013 +0000
@@ -96,4 +96,38 @@
CANMessage generate(void);
};
+class GMLAN_11Bit_Request {
+ /*
+ Class to allow easier handling of sending and receiving 11-bit messages
+ */
+ private:
+ vector<char> request_data, response_data;
+ int id, request_state;
+ int tx_frame_counter, tx_bytes;
+ int rx_frame_counter, rx_bytes;
+
+ char frame_padding [8];
+
+ public:
+ // (Main function) Create message and send it
+ GMLAN_11Bit_Request(int _id, vector<char> _request);
+
+ // Process each frame to transmit and flow control frame if needed
+ CANMessage getNextFrame(void);
+ CANMessage getFlowControl(void);
+ // Process each received frame
+ void processFrame(CANMessage msg);
+
+ // Handle starting and flow control
+ void start(void) { request_state = GMLAN_STATE_SEND_DATA; }
+ void continueFlow(void) { request_state = GMLAN_STATE_SEND_DATA; }
+
+ // Return request_state to confirm status
+ int getState(void) { return request_state; }
+ // Return ID
+ int getID(void) { return id; }
+ // Return response
+ vector<char> getResponse(void) { return response_data; }
+};
+
#endif
\ No newline at end of file
--- a/GMLAN_11bit.h Tue Mar 19 10:03:21 2013 +0000 +++ b/GMLAN_11bit.h Wed Apr 03 16:09:10 2013 +0000 @@ -19,6 +19,7 @@ #ifndef GMLAN_11BIT_H #define GMLAN_11BIT_H +// CAN IDs #define GMLAN_INITIAL_WAKE_UP_REQUEST 0x100 #define GMLAN_REQUEST_TO_ALL_NODES 0x101 #define GMLAN_DIAGNOSTIC_REQUEST 0x102 @@ -49,4 +50,42 @@ #define GMLAN_ECM_TO_EXTERNAL_OBD_TEST_EQUIPMENT 0x7E8 #define GMLAN_SPECIFIC_OBD_COMPLIANT_ECU_TO_EXTERNAL_OBD_TEST_EQUIPMENT 0x7E9 +// PCI byte +#define GMLAN_PCI_UNSEGMENTED 0x0 +#define GMLAN_PCI_SEGMENTED 0x1 +#define GMLAN_PCI_ADDITIONAL 0x2 +#define GMLAN_PCI_FLOW_CONTROL 0x3 + +// Service ID byte +#define GMLAN_SID_CLEAR_DTC 0x4 +#define GMLAN_SID_START_DIAG 0x10 +#define GMLAN_SID_REQ_FAIL_RECS 0x12 +#define GMLAN_SID_REQ_DID 0x1A +#define GMLAN_SID_RES_NORM_OP 0x20 +#define GMLAN_SID_REQ_PID 0x22 +#define GMLAN_SID_READ_ADDR 0x23 +#define GMLAN_SID_REQ_SEC_ACCESS 0x27 +#define GMLAN_SID_DSBL_NORM_OP 0x28 +#define GMLAN_SID_DEF_DPID_MSG 0x2C +#define GMLAN_SID_DEF_PID_BY_ADDR 0x2D +#define GMLAN_SID_DL_REQ 0x34 +#define GMLAN_SID_DATA_TRANS 0x36 +#define GMLAN_SID_WRITE_DID 0x3B +#define GMLAN_SID_TESTER_PRESENT 0x3E +#define GMLAN_SID_ERROR 0x7F +#define GMLAN_SID_REQ_PROG_STATE 0xA2 +#define GMLAN_SID_PROG_MODE 0xA5 +#define GMLAN_SID_READ_DTC 0xA9 +#define GMLAN_SID_REQ_DPID 0xAA +#define GMLAN_SID_REQ_CONTROL 0xAE + +// States of request +#define GMLAN_STATE_READY_TO_SEND 0x0 +#define GMLAN_STATE_SEND_DATA 0x1 +#define GMLAN_STATE_AWAITING_FC 0x2 +#define GMLAN_STATE_AWAITING_REPLY 0x3 +#define GMLAN_STATE_SEND_FC 0x4 +#define GMLAN_STATE_COMPLETED 0x5 +#define GMLAN_STATE_ERROR 0x6 + #endif \ No newline at end of file