Mbed OS Reference | CAN.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2006-2019 ARM Limited
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 #ifndef MBED_CAN_H
 #define MBED_CAN_H
 
 #include "platform/platform.h"
 
 #if DEVICE_CAN || defined(DOXYGEN_ONLY)
 
 #include "hal/can_api.h"
 #include "platform/Callback.h"
 #include "platform/PlatformMutex.h"
 #include "platform/NonCopyable.h"
 
 namespace mbed {
 /** \defgroup drivers-public-api-can CAN
  * \ingroup drivers-public-api
  */
 
 /**
  * \defgroup drivers_CANMessage CANMessage class
  * \ingroup drivers-public-api-can
  * @{
  */
 
 /** CANMessage class
  *
  * @note Synchronization level: Thread safe
  */
 class CANMessage : public CAN_Message {
 
 public:
     /** Creates empty CAN message.
      */
     CANMessage() : CAN_Message()
     {
         len    = 8U;
         type   = CANData;
         format = CANStandard;
         id     = 0U;
         memset(data, 0, 8);
     }
 
     /** Creates CAN message with specific content.
      *
      *  @param _id      Message ID
      *  @param _data    Mesaage Data
      *  @param _len     Message Data length
      *  @param _type    Type of Data: Use enum CANType for valid parameter values
      *  @param _format  Data Format: Use enum CANFormat for valid parameter values
      */
     CANMessage(unsigned int _id, const unsigned char *_data, unsigned char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard)
     {
         len    = _len & 0xF;
         type   = _type;
         format = _format;
         id     = _id;
         memcpy(data, _data, _len);
     }
 
 
     /** Creates CAN message with specific content.
      *
      *  @param _id      Message ID
      *  @param _data    Mesaage Data
      *  @param _len     Message Data length
      *  @param _type    Type of Data: Use enum CANType for valid parameter values
      *  @param _format  Data Format: Use enum CANFormat for valid parameter values
      */
     CANMessage(unsigned int _id, const char *_data, unsigned char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard)
     {
         len    = _len & 0xF;
         type   = _type;
         format = _format;
         id     = _id;
         memcpy(data, _data, _len);
     }
 
     /** Creates CAN remote message.
      *
      *  @param _id      Message ID
      *  @param _format  Data Format: Use enum CANType for valid parameter values
      */
     CANMessage(unsigned int _id, CANFormat _format = CANStandard)
     {
         len    = 0;
         type   = CANRemote;
         format = _format;
         id     = _id;
         memset(data, 0, 8);
     }
 };
 
 /** @}*/
 
 /**
  * \defgroup drivers_CAN CAN class
  * \ingroup drivers-public-api-can
  * @{
  */
 
 /** A can bus client, used for communicating with can devices
  */
 class CAN : private NonCopyable<CAN> {
 
 public:
     /** Creates a CAN interface connected to specific pins.
      *
      *  @param rd read from transmitter
      *  @param td transmit to transmitter
      *
      * Example:
      * @code
      * #include "mbed.h"
      *
      *
      * Ticker ticker;
      * DigitalOut led1(LED1);
      * DigitalOut led2(LED2);
      * //The constructor takes in RX, and TX pin respectively.
      * //These pins, for this example, are defined in mbed_app.json
      * CAN can1(MBED_CONF_APP_CAN1_RD, MBED_CONF_APP_CAN1_TD);
      * CAN can2(MBED_CONF_APP_CAN2_RD, MBED_CONF_APP_CAN2_TD);
      *
      * unsigned char counter = 0;
      *
      * void send() {
      *     if(can1.write(CANMessage(1337U, &counter, 1))) {
      *         printf("Message sent: %d\n", counter);
      *         counter++;
      *     }
      *     led1 = !led1;
      * }
      *
      * int main() {
      *     ticker.attach(&send, 1);
      *     CANMessage msg;
      *     while(1) {
      *         if(can2.read(msg)) {
      *             printf("Message received: %d\n\n", msg.data[0]);
      *             led2 = !led2;
      *         }
      *         wait(0.2);
      *     }
      * }
      *
      * @endcode
      */
     CAN(PinName rd, PinName td);
 
     /** Initialize CAN interface and set the frequency
       *
       * @param rd the read pin
       * @param td the transmit pin
       * @param hz the bus frequency in hertz
       */
     CAN(PinName rd, PinName td, int hz);
 
     virtual ~CAN();
 
     /** Set the frequency of the CAN interface
      *
      *  @param hz The bus frequency in hertz
      *
      *  @returns
      *    1 if successful,
      *    0 otherwise
      */
     int frequency(int hz);
 
     /** Write a CANMessage to the bus.
      *
      *  @param msg The CANMessage to write.
      *
      *  @returns
      *    0 if write failed,
      *    1 if write was successful
      */
     int write(CANMessage msg);
 
     /** Read a CANMessage from the bus.
      *
      *  @param msg A CANMessage to read to.
      *  @param handle message filter handle (0 for any message)
      *
      *  @returns
      *    0 if no message arrived,
      *    1 if message arrived
      */
     int read(CANMessage &msg, int handle = 0);
 
     /** Reset CAN interface.
      *
      * To use after error overflow.
      */
     void reset();
 
     /** Puts or removes the CAN interface into silent monitoring mode
      *
      *  @param silent boolean indicating whether to go into silent mode or not
      */
     void monitor(bool silent);
 
     enum Mode {
         Reset = 0,
         Normal,
         Silent,
         LocalTest,
         GlobalTest,
         SilentTest
     };
 
     /** Change CAN operation to the specified mode
      *
      *  @param mode The new operation mode (CAN::Normal, CAN::Silent, CAN::LocalTest, CAN::GlobalTest, CAN::SilentTest)
      *
      *  @returns
      *    0 if mode change failed or unsupported,
      *    1 if mode change was successful
      */
     int mode(Mode mode);
 
     /** Filter out incoming messages
      *
      *  @param id the id to filter on
      *  @param mask the mask applied to the id
      *  @param format format to filter on (Default CANAny)
      *  @param handle message filter handle (Optional)
      *
      *  @returns
      *    0 if filter change failed or unsupported,
      *    new filter handle if successful
      */
     int filter(unsigned int id, unsigned int mask, CANFormat format = CANAny, int handle = 0);
 
     /**  Detects read errors - Used to detect read overflow errors.
      *
      *  @returns number of read errors
      */
     unsigned char rderror();
 
     /** Detects write errors - Used to detect write overflow errors.
      *
      *  @returns number of write errors
      */
     unsigned char tderror();
 
     enum IrqType {
         RxIrq = 0,
         TxIrq,
         EwIrq,
         DoIrq,
         WuIrq,
         EpIrq,
         AlIrq,
         BeIrq,
         IdIrq,
 
         IrqCnt
     };
 
     /** Attach a function to call whenever a CAN frame received interrupt is
      *  generated.
      *
      *  This function locks the deep sleep while a callback is attached
      *
      *  @param func A pointer to a void function, or 0 to set as none
      *  @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)
      */
     void attach(Callback<void()> func, IrqType type = RxIrq);
 
     /** Attach a member function to call whenever a CAN frame received interrupt
      *  is generated.
      *
      *  @param obj pointer to the object to call the member function on
      *  @param method pointer to the member function to be called
      *  @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)
      *  @deprecated
      *      The attach function does not support cv-qualifiers. Replaced by
      *      attach(callback(obj, method), type).
      */
     template<typename T>
     MBED_DEPRECATED_SINCE("mbed-os-5.1",
                           "The attach function does not support cv-qualifiers. Replaced by "
                           "attach(callback(obj, method), type).")
     void attach(T *obj, void (T::*method)(), IrqType type = RxIrq)
     {
         // Underlying call thread safe
         attach(callback(obj, method), type);
     }
 
     /** Attach a member function to call whenever a CAN frame received interrupt
      *  is generated.
      *
      *  @param obj pointer to the object to call the member function on
      *  @param method pointer to the member function to be called
      *  @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)
      *  @deprecated
      *      The attach function does not support cv-qualifiers. Replaced by
      *      attach(callback(obj, method), type).
      */
     template<typename T>
     MBED_DEPRECATED_SINCE("mbed-os-5.1",
                           "The attach function does not support cv-qualifiers. Replaced by "
                           "attach(callback(obj, method), type).")
     void attach(T *obj, void (*method)(T *), IrqType type = RxIrq)
     {
         // Underlying call thread safe
         attach(callback(obj, method), type);
     }
 
     static void _irq_handler(uint32_t id, CanIrqType type);
 
 #if !defined(DOXYGEN_ONLY)
 protected:
     virtual void lock();
     virtual void unlock();
 
     can_t               _can;
     Callback<void()>    _irq[IrqCnt];
     PlatformMutex       _mutex;
 #endif
 };
 
 /** @}*/
 
 } // namespace mbed
 
 #endif
 
 #endif    // MBED_CAN_H
 
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