CAN.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_CAN_H
00017 #define MBED_CAN_H
00018 
00019 #include "platform/platform.h"
00020 
00021 #if defined (DEVICE_CAN) || defined(DOXYGEN_ONLY)
00022 
00023 #include "hal/can_api.h"
00024 #include "platform/Callback.h"
00025 #include "platform/PlatformMutex.h"
00026 #include "platform/NonCopyable.h"
00027 
00028 namespace mbed {
00029 /** \addtogroup drivers */
00030 
00031 /** CANMessage class
00032  *
00033  * @note Synchronization level: Thread safe
00034  * @ingroup drivers
00035  */
00036 class CANMessage : public CAN_Message {
00037 
00038 public:
00039     /** Creates empty CAN message.
00040      */
00041     CANMessage() : CAN_Message() {
00042         len    = 8;
00043         type   = CANData;
00044         format = CANStandard;
00045         id     = 0;
00046         memset(data, 0, 8);
00047     }
00048 
00049     /** Creates CAN message with specific content.
00050      *
00051      *  @param _id      Message ID
00052      *  @param _data    Mesaage Data
00053      *  @param _len     Message Data length
00054      *  @param _type    Type of Data: Use enum CANType for valid parameter values
00055      *  @param _format  Data Format: Use enum CANFormat for valid parameter values
00056      */
00057     CANMessage(int _id, const char *_data, char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard) {
00058       len    = _len & 0xF;
00059       type   = _type;
00060       format = _format;
00061       id     = _id;
00062       memcpy(data, _data, _len);
00063     }
00064 
00065     /** Creates CAN remote message.
00066      *
00067      *  @param _id      Message ID
00068      *  @param _format  Data Format: Use enum CANType for valid parameter values
00069      */
00070     CANMessage(int _id, CANFormat _format = CANStandard) {
00071       len    = 0;
00072       type   = CANRemote;
00073       format = _format;
00074       id     = _id;
00075       memset(data, 0, 8);
00076     }
00077 };
00078 
00079 /** A can bus client, used for communicating with can devices
00080  * @ingroup drivers
00081  */
00082 class CAN : private NonCopyable<CAN> {
00083 
00084 public:
00085     /** Creates an CAN interface connected to specific pins.
00086      *
00087      *  @param rd read from transmitter
00088      *  @param td transmit to transmitter
00089      *
00090      * Example:
00091      * @code
00092      * #include "mbed.h"
00093      *
00094      * Ticker ticker;
00095      * DigitalOut led1(LED1);
00096      * DigitalOut led2(LED2);
00097      * CAN can1(p9, p10);
00098      * CAN can2(p30, p29);
00099      *
00100      * char counter = 0;
00101      *
00102      * void send() {
00103      *     if(can1.write(CANMessage(1337, &counter, 1))) {
00104      *         printf("Message sent: %d\n", counter);
00105      *         counter++;
00106      *     }
00107      *     led1 = !led1;
00108      * }
00109      *
00110      * int main() {
00111      *     ticker.attach(&send, 1);
00112      *    CANMessage msg;
00113      *     while(1) {
00114      *         if(can2.read(msg)) {
00115      *             printf("Message received: %d\n\n", msg.data[0]);
00116      *             led2 = !led2;
00117      *         }
00118      *         wait(0.2);
00119      *     }
00120      * }
00121      * @endcode
00122      */
00123     CAN(PinName rd, PinName td);
00124 
00125     /** Initialize CAN interface and set the frequency
00126       *
00127       * @param rd the rd pin
00128       * @param td the td pin
00129       * @param hz the bus frequency in hertz
00130       */
00131     CAN(PinName rd, PinName td, int hz);
00132 
00133     virtual ~CAN();
00134 
00135     /** Set the frequency of the CAN interface
00136      *
00137      *  @param hz The bus frequency in hertz
00138      *
00139      *  @returns
00140      *    1 if successful,
00141      *    0 otherwise
00142      */
00143     int frequency(int hz);
00144 
00145     /** Write a CANMessage to the bus.
00146      *
00147      *  @param msg The CANMessage to write.
00148      *
00149      *  @returns
00150      *    0 if write failed,
00151      *    1 if write was successful
00152      */
00153     int write(CANMessage msg);
00154 
00155     /** Read a CANMessage from the bus.
00156      *
00157      *  @param msg A CANMessage to read to.
00158      *  @param handle message filter handle (0 for any message)
00159      *
00160      *  @returns
00161      *    0 if no message arrived,
00162      *    1 if message arrived
00163      */
00164     int read(CANMessage &msg, int handle = 0);
00165 
00166     /** Reset CAN interface.
00167      *
00168      * To use after error overflow.
00169      */
00170     void reset();
00171 
00172     /** Puts or removes the CAN interface into silent monitoring mode
00173      *
00174      *  @param silent boolean indicating whether to go into silent mode or not
00175      */
00176     void monitor(bool silent);
00177 
00178     enum Mode {
00179         Reset = 0,
00180         Normal,
00181         Silent,
00182         LocalTest,
00183         GlobalTest,
00184         SilentTest
00185     };
00186 
00187     /** Change CAN operation to the specified mode
00188      *
00189      *  @param mode The new operation mode (CAN::Normal, CAN::Silent, CAN::LocalTest, CAN::GlobalTest, CAN::SilentTest)
00190      *
00191      *  @returns
00192      *    0 if mode change failed or unsupported,
00193      *    1 if mode change was successful
00194      */
00195     int mode(Mode mode);
00196 
00197     /** Filter out incomming messages
00198      *
00199      *  @param id the id to filter on
00200      *  @param mask the mask applied to the id
00201      *  @param format format to filter on (Default CANAny)
00202      *  @param handle message filter handle (Optional)
00203      *
00204      *  @returns
00205      *    0 if filter change failed or unsupported,
00206      *    new filter handle if successful
00207      */
00208     int filter(unsigned int id, unsigned int mask, CANFormat format = CANAny, int handle = 0);
00209 
00210     /**  Detects read errors - Used to detect read overflow errors.
00211      *
00212      *  @returns number of read errors
00213      */
00214     unsigned char rderror();
00215 
00216     /** Detects write errors - Used to detect write overflow errors.
00217      *
00218      *  @returns number of write errors
00219      */
00220     unsigned char tderror();
00221 
00222     enum IrqType {
00223         RxIrq = 0,
00224         TxIrq,
00225         EwIrq,
00226         DoIrq,
00227         WuIrq,
00228         EpIrq,
00229         AlIrq,
00230         BeIrq,
00231         IdIrq,
00232 
00233         IrqCnt
00234     };
00235 
00236     /** Attach a function to call whenever a CAN frame received interrupt is
00237      *  generated.
00238      *
00239      *  @param func A pointer to a void function, or 0 to set as none
00240      *  @param type Which CAN interrupt to attach the member function to (CAN::RxIrq for message received, CAN::TxIrq for transmitted or aborted, CAN::EwIrq for error warning, CAN::DoIrq for data overrun, CAN::WuIrq for wake-up, CAN::EpIrq for error passive, CAN::AlIrq for arbitration lost, CAN::BeIrq for bus error)
00241      */
00242     void attach(Callback<void()> func, IrqType type=RxIrq);
00243 
00244    /** Attach a member function to call whenever a CAN frame received interrupt
00245     *  is generated.
00246     *
00247     *  @param obj pointer to the object to call the member function on
00248     *  @param method pointer to the member function to be called
00249     *  @param type Which CAN interrupt to attach the member function to (CAN::RxIrq for message received, TxIrq for transmitted or aborted, EwIrq for error warning, DoIrq for data overrun, WuIrq for wake-up, EpIrq for error passive, AlIrq for arbitration lost, BeIrq for bus error)
00250     *  @deprecated
00251     *      The attach function does not support cv-qualifiers. Replaced by
00252     *      attach(callback(obj, method), type).
00253     */
00254     template<typename T>
00255     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00256         "The attach function does not support cv-qualifiers. Replaced by "
00257         "attach(callback(obj, method), type).")
00258     void attach(T* obj, void (T::*method)(), IrqType type=RxIrq) {
00259         // Underlying call thread safe
00260         attach(callback(obj, method), type);
00261     }
00262 
00263    /** Attach a member function to call whenever a CAN frame received interrupt
00264     *  is generated.
00265     *
00266     *  @param obj pointer to the object to call the member function on
00267     *  @param method pointer to the member function to be called
00268     *  @param type Which CAN interrupt to attach the member function to (CAN::RxIrq for message received, TxIrq for transmitted or aborted, EwIrq for error warning, DoIrq for data overrun, WuIrq for wake-up, EpIrq for error passive, AlIrq for arbitration lost, BeIrq for bus error)
00269     *  @deprecated
00270     *      The attach function does not support cv-qualifiers. Replaced by
00271     *      attach(callback(obj, method), type).
00272     */
00273     template<typename T>
00274     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00275         "The attach function does not support cv-qualifiers. Replaced by "
00276         "attach(callback(obj, method), type).")
00277     void attach(T* obj, void (*method)(T*), IrqType type=RxIrq) {
00278         // Underlying call thread safe
00279         attach(callback(obj, method), type);
00280     }
00281 
00282     static void _irq_handler(uint32_t id, CanIrqType type);
00283 
00284 protected:
00285     virtual void lock();
00286     virtual void unlock();
00287     can_t               _can;
00288     Callback<void()>    _irq[IrqCnt];
00289     PlatformMutex       _mutex;
00290 };
00291 
00292 } // namespace mbed
00293 
00294 #endif
00295 
00296 #endif    // MBED_CAN_H
00297