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 
00027 namespace mbed {
00028 /** \addtogroup drivers */
00029 
00030 /** CANMessage class
00031  *
00032  * @note Synchronization level: Thread safe
00033  * @ingroup drivers
00034  */
00035 class CANMessage : public CAN_Message {
00036 
00037 public:
00038     /** Creates empty CAN message.
00039      */
00040     CANMessage() : CAN_Message() {
00041         len    = 8;
00042         type   = CANData;
00043         format = CANStandard;
00044         id     = 0;
00045         memset(data, 0, 8);
00046     }
00047 
00048     /** Creates CAN message with specific content.
00049      */
00050     CANMessage(int _id, const char *_data, char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard) {
00051       len    = _len & 0xF;
00052       type   = _type;
00053       format = _format;
00054       id     = _id;
00055       memcpy(data, _data, _len);
00056     }
00057 
00058     /** Creates CAN remote message.
00059      */
00060     CANMessage(int _id, CANFormat _format = CANStandard) {
00061       len    = 0;
00062       type   = CANRemote;
00063       format = _format;
00064       id     = _id;
00065       memset(data, 0, 8);
00066     }
00067 };
00068 
00069 /** A can bus client, used for communicating with can devices
00070  * @ingroup drivers
00071  */
00072 class CAN {
00073 
00074 public:
00075     /** Creates an CAN interface connected to specific pins.
00076      *
00077      *  @param rd read from transmitter
00078      *  @param td transmit to transmitter
00079      *
00080      * Example:
00081      * @code
00082      * #include "mbed.h"
00083      *
00084      * Ticker ticker;
00085      * DigitalOut led1(LED1);
00086      * DigitalOut led2(LED2);
00087      * CAN can1(p9, p10);
00088      * CAN can2(p30, p29);
00089      *
00090      * char counter = 0;
00091      *
00092      * void send() {
00093      *     if(can1.write(CANMessage(1337, &counter, 1))) {
00094      *         printf("Message sent: %d\n", counter);
00095      *         counter++;
00096      *     }
00097      *     led1 = !led1;
00098      * }
00099      *
00100      * int main() {
00101      *     ticker.attach(&send, 1);
00102      *    CANMessage msg;
00103      *     while(1) {
00104      *         if(can2.read(msg)) {
00105      *             printf("Message received: %d\n\n", msg.data[0]);
00106      *             led2 = !led2;
00107      *         }
00108      *         wait(0.2);
00109      *     }
00110      * }
00111      * @endcode
00112      */
00113     CAN(PinName rd, PinName td);
00114 
00115     /** Initialize CAN interface and set the frequency
00116       *
00117       * @param rd the rd pin
00118       * @param td the td pin
00119       * @param hz the bus frequency in hertz
00120       */
00121     CAN(PinName rd, PinName td, int hz);
00122 
00123     virtual ~CAN();
00124 
00125     /** Set the frequency of the CAN interface
00126      *
00127      *  @param hz The bus frequency in hertz
00128      *
00129      *  @returns
00130      *    1 if successful,
00131      *    0 otherwise
00132      */
00133     int frequency(int hz);
00134 
00135     /** Write a CANMessage to the bus.
00136      *
00137      *  @param msg The CANMessage to write.
00138      *
00139      *  @returns
00140      *    0 if write failed,
00141      *    1 if write was successful
00142      */
00143     int write(CANMessage msg);
00144 
00145     /** Read a CANMessage from the bus.
00146      *
00147      *  @param msg A CANMessage to read to.
00148      *  @param handle message filter handle (0 for any message)
00149      *
00150      *  @returns
00151      *    0 if no message arrived,
00152      *    1 if message arrived
00153      */
00154     int read(CANMessage &msg, int handle = 0);
00155 
00156     /** Reset CAN interface.
00157      *
00158      * To use after error overflow.
00159      */
00160     void reset();
00161 
00162     /** Puts or removes the CAN interface into silent monitoring mode
00163      *
00164      *  @param silent boolean indicating whether to go into silent mode or not
00165      */
00166     void monitor(bool silent);
00167 
00168     enum Mode {
00169         Reset = 0,
00170         Normal,
00171         Silent,
00172         LocalTest,
00173         GlobalTest,
00174         SilentTest
00175     };
00176 
00177     /** Change CAN operation to the specified mode
00178      *
00179      *  @param mode The new operation mode (CAN::Normal, CAN::Silent, CAN::LocalTest, CAN::GlobalTest, CAN::SilentTest)
00180      *
00181      *  @returns
00182      *    0 if mode change failed or unsupported,
00183      *    1 if mode change was successful
00184      */
00185     int mode(Mode mode);
00186 
00187     /** Filter out incomming messages
00188      *
00189      *  @param id the id to filter on
00190      *  @param mask the mask applied to the id
00191      *  @param format format to filter on (Default CANAny)
00192      *  @param handle message filter handle (Optional)
00193      *
00194      *  @returns
00195      *    0 if filter change failed or unsupported,
00196      *    new filter handle if successful
00197      */
00198     int filter(unsigned int id, unsigned int mask, CANFormat format = CANAny, int handle = 0);
00199 
00200     /** Returns number of read errors to detect read overflow errors.
00201      */
00202     unsigned char rderror();
00203 
00204     /** Returns number of write errors to detect write overflow errors.
00205      */
00206     unsigned char tderror();
00207 
00208     enum IrqType {
00209         RxIrq = 0,
00210         TxIrq,
00211         EwIrq,
00212         DoIrq,
00213         WuIrq,
00214         EpIrq,
00215         AlIrq,
00216         BeIrq,
00217         IdIrq,
00218 
00219         IrqCnt
00220     };
00221 
00222     /** Attach a function to call whenever a CAN frame received interrupt is
00223      *  generated.
00224      *
00225      *  @param func A pointer to a void function, or 0 to set as none
00226      *  @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)
00227      */
00228     void attach(Callback<void()> func, IrqType type=RxIrq);
00229 
00230    /** Attach a member function to call whenever a CAN frame received interrupt
00231     *  is generated.
00232     *
00233     *  @param obj pointer to the object to call the member function on
00234     *  @param method pointer to the member function to be called
00235     *  @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)
00236     *  @deprecated
00237     *      The attach function does not support cv-qualifiers. Replaced by
00238     *      attach(callback(obj, method), type).
00239     */
00240     template<typename T>
00241     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00242         "The attach function does not support cv-qualifiers. Replaced by "
00243         "attach(callback(obj, method), type).")
00244     void attach(T* obj, void (T::*method)(), IrqType type=RxIrq) {
00245         // Underlying call thread safe
00246         attach(callback(obj, method), type);
00247     }
00248 
00249    /** Attach a member function to call whenever a CAN frame received interrupt
00250     *  is generated.
00251     *
00252     *  @param obj pointer to the object to call the member function on
00253     *  @param method pointer to the member function to be called
00254     *  @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)
00255     *  @deprecated
00256     *      The attach function does not support cv-qualifiers. Replaced by
00257     *      attach(callback(obj, method), type).
00258     */
00259     template<typename T>
00260     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00261         "The attach function does not support cv-qualifiers. Replaced by "
00262         "attach(callback(obj, method), type).")
00263     void attach(T* obj, void (*method)(T*), IrqType type=RxIrq) {
00264         // Underlying call thread safe
00265         attach(callback(obj, method), type);
00266     }
00267 
00268     static void _irq_handler(uint32_t id, CanIrqType type);
00269 
00270 protected:
00271     virtual void lock();
00272     virtual void unlock();
00273     can_t               _can;
00274     Callback<void()>    _irq[IrqCnt];
00275     PlatformMutex       _mutex;
00276 };
00277 
00278 } // namespace mbed
00279 
00280 #endif
00281 
00282 #endif    // MBED_CAN_H
00283 
00284