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      *  @param _id      Message ID
00051      *  @param _data    Mesaage Data
00052      *  @param _len     Message Data length
00053      *  @param _type    Type of Data: Use enum CANType for valid parameter values
00054      *  @param _format  Data Format: Use enum CANFormat for valid parameter values
00055      */
00056     CANMessage(int _id, const char *_data, char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard) {
00057       len    = _len & 0xF;
00058       type   = _type;
00059       format = _format;
00060       id     = _id;
00061       memcpy(data, _data, _len);
00062     }
00063 
00064     /** Creates CAN remote message.
00065      *
00066      *  @param _id      Message ID
00067      *  @param _format  Data Format: Use enum CANType for valid parameter values
00068      */
00069     CANMessage(int _id, CANFormat _format = CANStandard) {
00070       len    = 0;
00071       type   = CANRemote;
00072       format = _format;
00073       id     = _id;
00074       memset(data, 0, 8);
00075     }
00076 };
00077 
00078 /** A can bus client, used for communicating with can devices
00079  * @ingroup drivers
00080  */
00081 class CAN {
00082 
00083 public:
00084     /** Creates an CAN interface connected to specific pins.
00085      *
00086      *  @param rd read from transmitter
00087      *  @param td transmit to transmitter
00088      *
00089      * Example:
00090      * @code
00091      * #include "mbed.h"
00092      *
00093      * Ticker ticker;
00094      * DigitalOut led1(LED1);
00095      * DigitalOut led2(LED2);
00096      * CAN can1(p9, p10);
00097      * CAN can2(p30, p29);
00098      *
00099      * char counter = 0;
00100      *
00101      * void send() {
00102      *     if(can1.write(CANMessage(1337, &counter, 1))) {
00103      *         printf("Message sent: %d\n", counter);
00104      *         counter++;
00105      *     }
00106      *     led1 = !led1;
00107      * }
00108      *
00109      * int main() {
00110      *     ticker.attach(&send, 1);
00111      *    CANMessage msg;
00112      *     while(1) {
00113      *         if(can2.read(msg)) {
00114      *             printf("Message received: %d\n\n", msg.data[0]);
00115      *             led2 = !led2;
00116      *         }
00117      *         wait(0.2);
00118      *     }
00119      * }
00120      * @endcode
00121      */
00122     CAN(PinName rd, PinName td);
00123 
00124     /** Initialize CAN interface and set the frequency
00125       *
00126       * @param rd the rd pin
00127       * @param td the td pin
00128       * @param hz the bus frequency in hertz
00129       */
00130     CAN(PinName rd, PinName td, int hz);
00131 
00132     virtual ~CAN();
00133 
00134     /** Set the frequency of the CAN interface
00135      *
00136      *  @param hz The bus frequency in hertz
00137      *
00138      *  @returns
00139      *    1 if successful,
00140      *    0 otherwise
00141      */
00142     int frequency(int hz);
00143 
00144     /** Write a CANMessage to the bus.
00145      *
00146      *  @param msg The CANMessage to write.
00147      *
00148      *  @returns
00149      *    0 if write failed,
00150      *    1 if write was successful
00151      */
00152     int write(CANMessage msg);
00153 
00154     /** Read a CANMessage from the bus.
00155      *
00156      *  @param msg A CANMessage to read to.
00157      *  @param handle message filter handle (0 for any message)
00158      *
00159      *  @returns
00160      *    0 if no message arrived,
00161      *    1 if message arrived
00162      */
00163     int read(CANMessage &msg, int handle = 0);
00164 
00165     /** Reset CAN interface.
00166      *
00167      * To use after error overflow.
00168      */
00169     void reset();
00170 
00171     /** Puts or removes the CAN interface into silent monitoring mode
00172      *
00173      *  @param silent boolean indicating whether to go into silent mode or not
00174      */
00175     void monitor(bool silent);
00176 
00177     enum Mode {
00178         Reset = 0,
00179         Normal,
00180         Silent,
00181         LocalTest,
00182         GlobalTest,
00183         SilentTest
00184     };
00185 
00186     /** Change CAN operation to the specified mode
00187      *
00188      *  @param mode The new operation mode (CAN::Normal, CAN::Silent, CAN::LocalTest, CAN::GlobalTest, CAN::SilentTest)
00189      *
00190      *  @returns
00191      *    0 if mode change failed or unsupported,
00192      *    1 if mode change was successful
00193      */
00194     int mode(Mode mode);
00195 
00196     /** Filter out incomming messages
00197      *
00198      *  @param id the id to filter on
00199      *  @param mask the mask applied to the id
00200      *  @param format format to filter on (Default CANAny)
00201      *  @param handle message filter handle (Optional)
00202      *
00203      *  @returns
00204      *    0 if filter change failed or unsupported,
00205      *    new filter handle if successful
00206      */
00207     int filter(unsigned int id, unsigned int mask, CANFormat format = CANAny, int handle = 0);
00208 
00209     /**  Detects read errors - Used to detect read overflow errors.
00210      *
00211      *  @returns number of read errors
00212      */
00213     unsigned char rderror();
00214 
00215     /** Detects write errors - Used to detect write overflow errors.
00216      *
00217      *  @returns number of write errors
00218      */
00219     unsigned char tderror();
00220 
00221     enum IrqType {
00222         RxIrq = 0,
00223         TxIrq,
00224         EwIrq,
00225         DoIrq,
00226         WuIrq,
00227         EpIrq,
00228         AlIrq,
00229         BeIrq,
00230         IdIrq,
00231 
00232         IrqCnt
00233     };
00234 
00235     /** Attach a function to call whenever a CAN frame received interrupt is
00236      *  generated.
00237      *
00238      *  @param func A pointer to a void function, or 0 to set as none
00239      *  @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)
00240      */
00241     void attach(Callback<void()> func, IrqType type=RxIrq);
00242 
00243    /** Attach a member function to call whenever a CAN frame received interrupt
00244     *  is generated.
00245     *
00246     *  @param obj pointer to the object to call the member function on
00247     *  @param method pointer to the member function to be called
00248     *  @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)
00249     *  @deprecated
00250     *      The attach function does not support cv-qualifiers. Replaced by
00251     *      attach(callback(obj, method), type).
00252     */
00253     template<typename T>
00254     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00255         "The attach function does not support cv-qualifiers. Replaced by "
00256         "attach(callback(obj, method), type).")
00257     void attach(T* obj, void (T::*method)(), IrqType type=RxIrq) {
00258         // Underlying call thread safe
00259         attach(callback(obj, method), type);
00260     }
00261 
00262    /** Attach a member function to call whenever a CAN frame received interrupt
00263     *  is generated.
00264     *
00265     *  @param obj pointer to the object to call the member function on
00266     *  @param method pointer to the member function to be called
00267     *  @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)
00268     *  @deprecated
00269     *      The attach function does not support cv-qualifiers. Replaced by
00270     *      attach(callback(obj, method), type).
00271     */
00272     template<typename T>
00273     MBED_DEPRECATED_SINCE("mbed-os-5.1",
00274         "The attach function does not support cv-qualifiers. Replaced by "
00275         "attach(callback(obj, method), type).")
00276     void attach(T* obj, void (*method)(T*), IrqType type=RxIrq) {
00277         // Underlying call thread safe
00278         attach(callback(obj, method), type);
00279     }
00280 
00281     static void _irq_handler(uint32_t id, CanIrqType type);
00282 
00283 protected:
00284     virtual void lock();
00285     virtual void unlock();
00286     can_t               _can;
00287     Callback<void()>    _irq[IrqCnt];
00288     PlatformMutex       _mutex;
00289 };
00290 
00291 } // namespace mbed
00292 
00293 #endif
00294 
00295 #endif    // MBED_CAN_H
00296