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diff --git a/CAN-binder/libs/uds-c/README.mkd b/CAN-binder/libs/uds-c/README.mkd deleted file mode 100644 index aa0d7fd..0000000 --- a/CAN-binder/libs/uds-c/README.mkd +++ /dev/null @@ -1,196 +0,0 @@ -Unified Diagnostic Services (UDS) Support Library in C -====================================================== - -This is a platform agnostic C library that implements the Unified Diagnostics -Services protocol for automotive electronics. UDS is documented in ISO 14229 and -is the underpinning for the more well-known On-board Diagnostics (OBD) standard. -The library currently supports UDS running over CAN (ISO 15765-4), which uses -the ISO-TP (ISO 15765-2) protocol for message framing. - -This library doesn't assume anything about the source of your diagnostic message -requests or underlying interface to the CAN bus. It uses dependency injection to -give you complete control. - -## Usage - -First, create some shim functions to let this library use your lower level -system: - - // required, this must send a single CAN message with the given arbitration - // ID (i.e. the CAN message ID) and data. The size will never be more than 8 - // bytes. - bool send_can(const uint32_t arbitration_id, const uint8_t* data, - const uint8_t size) { - ... - } - - // optional, provide to receive debugging log messages - void debug(const char* format, ...) { - ... - } - - - // not used in the current version - void set_timer(uint16_t time_ms, void (*callback)) { - ... - } - -With your shims in place, create a `DiagnosticShims` object to pass them around: - - DiagnosticShims shims = diagnostic_init_shims(debug, send_can, set_timer); - -With your shims in hand, send a simple PID request to the standard broadcast -address, `0x7df` (we use the constant `OBD2_FUNCTIONAL_BROADCAST_ID` here): - - // Optional: This is your callback that will be called the response to your - // diagnostic request is received. - void response_received_handler(const DiagnosticResponse* response) { - // You received a response! Do something with it. - } - - DiagnosticRequestHandle handle = diagnostic_request_pid(&shims, - DIAGNOSTIC_STANDARD_PID, // this is a standard PID request, not an extended or enhanced one - OBD2_FUNCTIONAL_BROADCAST_ID, // the request is going out to the broadcast arbitration ID - 0x2, // we want PID 0x2 - response_received_handler); // our callback (optional, use NULL if you don't have one) - - if(handle.completed) { - if(!handle.success) { - // something happened and it already failed - possibly we aren't - // able to send CAN messages - return; - } else { - // this should never occur right away - you need to receive a fresh - // CAN message first - } - } else { - while(true) { - // Continue to read from CAN, passing off each message to the handle. - // This will return a 'completed' DiagnosticResponse when the when - // the request is completely sent and the response is received - // (which may take more than 1 CAN frames) - DiagnosticResponse response = diagnostic_receive_can_frame(&shims, - &handle, can_message_id, can_data, sizeof(can_data)); - - if(response.completed && handle.completed) { - if(handle.success) { - if(response.success) { - // The request was sent successfully, the response was - // received successfully, and it was a positive response - we - // got back some data! - } else { - // The request was sent successfully, the response was - // received successfully, BUT it was a negative response - // from the other node. - printf("This is the error code: %d", response.negative_response_code); - } - } else { - // Some other fatal error ocurred - we weren't able to send - // the request or receive the response. The CAN connection - // may be down. - } - } - } - } - -### Requests for other modes - -If you want to do more besides PID requests on mode 0x1 and 0x22, there's a -lower level API you can use. Here's how to make a mode 3 request to get DTCs. - - DiagnosticRequest request = { - arbitration_id: OBD2_FUNCTIONAL_BROADCAST_ID, - mode: OBD2_MODE_EMISSIONS_DTC_REQUEST - }; - DiagnosticRequestHandle handle = diagnostic_request(&SHIMS, &request, NULL); - - if(handle.completed) { - if(!handle.success) { - // something happened and it already failed - possibly we aren't - // able to send CAN messages - return; - } else { - // this should never occur right away - you need to receive a fresh - // CAN message first - } - } else { - while(true) { - // Continue to read from CAN, passing off each message to the handle. - // This will return a 'completed' DiagnosticResponse when the when - // the request is completely sent and the response is received - // (which may take more than 1 CAN frames) - DiagnosticResponse response = diagnostic_receive_can_frame(&shims, - &handle, can_message_id, can_data, sizeof(can_data)); - - if(response.completed && handle.completed) { - if(handle.success) { - if(response.success) { - // The request was sent successfully, the response was - // received successfully, and it was a positive response - we - // got back some data! - printf("The DTCs are: "); - for(int i = 0; i < response.payload_length; i++) { - printf("0x%x ", response.payload[i]); - } - } else { - // The request was sent successfully, the response was - // received successfully, BUT it was a negative response - // from the other node. - printf("This is the error code: %d", response.negative_response_code); - } - } else { - // Some other fatal error ocurred - we weren't able to send - // the request or receive the response. The CAN connection - // may be down. - } - } - } - } - -## Dependencies - -This library requires 2 dependencies: - -* [isotp-c](https://github.com/openxc/isotp-c) -* [bitfield-c](https://github.com/openxc/bitfield-c) - -## Testing - -The library includes a test suite that uses the `check` C unit test library. - - $ make test - -You can also see the test coverage if you have `lcov` installed and the -`BROWSER` environment variable set to your choice of web browsers: - - $ BROWSER=google-chrome-stable make coverage - -## OBD-II Basics - -TODO diagram out a request, response and error response - -* store the request arb id, mode, pid, and payload locally -* send a can message -* get all new can messages passed to it -* Check the incoming can message to see if it matches one of the standard ECU - response IDs, or our arb ID + 0x8 -* if it matches, parse the diagnostic response and call the callback - - -## Future Notes - -you're going to request a few PIDs over and over again at some frequency -you're going to request DTCs once and read the response -you're going to clear DTCs once - -we need another layer on top of that to handle the repeated requests. - -## Authors - -Chris Peplin cpeplin@ford.com - -## License - -Copyright (c) 2013 Ford Motor Company - -Licensed under the BSD license. |