/** * CAN module object for generic microcontroller. * * This file is a template for other microcontrollers. * * @file CO_driver_target.h * @ingroup CO_driver * @author Janez Paternoster * @copyright 2004 - 2015 Janez Paternoster * * This file is part of CANopenNode, an opensource CANopen Stack. * Project home page is . * For more information on CANopen see . * * CANopenNode is free and open source software: you can redistribute * it and/or modify it under the terms of the GNU General Public License * as published by the Free Software Foundation, either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * Following clarification and special exception to the GNU General Public * License is included to the distribution terms of CANopenNode: * * Linking this library statically or dynamically with other modules is * making a combined work based on this library. Thus, the terms and * conditions of the GNU General Public License cover the whole combination. * * As a special exception, the copyright holders of this library give * you permission to link this library with independent modules to * produce an executable, regardless of the license terms of these * independent modules, and to copy and distribute the resulting * executable under terms of your choice, provided that you also meet, * for each linked independent module, the terms and conditions of the * license of that module. An independent module is a module which is * not derived from or based on this library. If you modify this * library, you may extend this exception to your version of the * library, but you are not obliged to do so. If you do not wish * to do so, delete this exception statement from your version. */ #ifndef CO_DRIVER_TARGET_H #define CO_DRIVER_TARGET_H #ifdef __cplusplus extern "C" { #endif /* Include processor header file */ #include /* for 'NULL' */ #include /* for 'int8_t' to 'uint64_t' */ #include /* for 'true', 'false' */ /** * Endianness. * * Depending on processor or compiler architecture, one of the two macros must * be defined: CO_LITTLE_ENDIAN or CO_BIG_ENDIAN. CANopen itself is little endian. */ #define CO_LITTLE_ENDIAN /** * @defgroup CO_driver Driver * @ingroup CO_CANopen * @{ * * Microcontroller specific code for CANopenNode. * * This file contains type definitions, functions and macros for: * - Basic data types. * - Receive and transmit buffers for CANopen messages. * - Interaction with CAN module on the microcontroller. * - CAN receive and transmit interrupts. * * This file is not only a CAN driver. There are no classic CAN queues for CAN * messages. This file provides direct connection with other CANopen * objects. It tries to provide fast responses and tries to avoid unnecessary * calculations and memory consumptions. * * CO_CANmodule_t contains an array of _Received message objects_ (of type * CO_CANrx_t) and an array of _Transmit message objects_ (of type CO_CANtx_t). * Each CANopen communication object owns one member in one of the arrays. * For example Heartbeat producer generates one CANopen transmitting object, * so it has reserved one member in CO_CANtx_t array. * SYNC module may produce sync or consume sync, so it has reserved one member * in CO_CANtx_t and one member in CO_CANrx_t array. * * ###Reception of CAN messages. * Before CAN messages can be received, each member in CO_CANrx_t must be * initialized. CO_CANrxBufferInit() is called by CANopen module, which * uses specific member. For example @ref CO_HBconsumer uses multiple members * in CO_CANrx_t array. (It monitors multiple heartbeat messages from remote * nodes.) It must call CO_CANrxBufferInit() multiple times. * * Main arguments to the CO_CANrxBufferInit() function are CAN identifier * and a pointer to callback function. Those two arguments (and some others) * are copied to the member of the CO_CANrx_t array. * * Callback function is a function, specified by specific CANopen module * (for example by @ref CO_HBconsumer). Each CANopen module defines own * callback function. Callback function will process the received CAN message. * It will copy the necessary data from CAN message to proper place. It may * also trigger additional task, which will further process the received message. * Callback function must be fast and must only make the necessary calculations * and copying. * * Received CAN messages are processed by CAN receive interrupt function. * After CAN message is received, function first tries to find matching CAN * identifier from CO_CANrx_t array. If found, then a corresponding callback * function is called. * * Callback function accepts two parameters: * - object is pointer to object registered by CO_CANrxBufferInit(). * - msg is pointer to CAN message of type CO_CANrxMsg_t. * * Callback function must return #CO_ReturnError_t: CO_ERROR_NO, * CO_ERROR_RX_OVERFLOW, CO_ERROR_RX_PDO_OVERFLOW, CO_ERROR_RX_MSG_LENGTH or * CO_ERROR_RX_PDO_LENGTH. * * * ###Transmission of CAN messages. * Before CAN messages can be transmitted, each member in CO_CANtx_t must be * initialized. CO_CANtxBufferInit() is called by CANopen module, which * uses specific member. For example Heartbeat producer must initialize it's * member in CO_CANtx_t array. * * CO_CANtxBufferInit() returns a pointer of type CO_CANtx_t, which contains buffer * where CAN message data can be written. CAN message is send with calling * CO_CANsend() function. If at that moment CAN transmit buffer inside * microcontroller's CAN module is free, message is copied directly to CAN module. * Otherwise CO_CANsend() function sets _bufferFull_ flag to true. Message will be * then sent by CAN TX interrupt as soon as CAN module is freed. Until message is * not copied to CAN module, its contents must not change. There may be multiple * _bufferFull_ flags in CO_CANtx_t array set to true. In that case messages with * lower index inside array will be sent first. */ /** * @name Critical sections * CANopenNode is designed to run in different threads, as described in README. * Threads are implemented differently in different systems. In microcontrollers * threads are interrupts with different priorities, for example. * It is necessary to protect sections, where different threads access to the * same resource. In simple systems interrupts or scheduler may be temporary * disabled between access to the shared resource. Otherwise mutexes or * semaphores can be used. * * ####Reentrant functions. * Functions CO_CANsend() from C_driver.h, CO_errorReport() from CO_Emergency.h * and CO_errorReset() from CO_Emergency.h may be called from different threads. * Critical sections must be protected. Eather by disabling scheduler or * interrupts or by mutexes or semaphores. * * ####Object Dictionary variables. * In general, there are two threads, which accesses OD variables: mainline and * timer. CANopenNode initialization and SDO server runs in mainline. PDOs runs * in faster timer thread. Processing of PDOs must not be interrupted by * mainline. Mainline thread must protect sections, which accesses the same OD * variables as timer thread. This care must also take the application. Note * that not all variables are allowed to be mapped to PDOs, so they may not need * to be protected. SDO server protects sections with access to OD variables. * * ####CAN receive thread. * It partially processes received CAN data and puts them into appropriate * objects. Objects are later processed. It does not need protection of * critical sections. There is one circumstance, where CANrx should be disabled: * After presence of SYNC message on CANopen bus, CANrx should be temporary * disabled until all receive PDOs are processed. See also CO_SYNC.h file and * CO_SYNC_initCallback() function. * @{ */ #define CO_LOCK_CAN_SEND() /**< Lock critical section in CO_CANsend() */ #define CO_UNLOCK_CAN_SEND()/**< Unlock critical section in CO_CANsend() */ #define CO_LOCK_EMCY() /**< Lock critical section in CO_errorReport() or CO_errorReset() */ #define CO_UNLOCK_EMCY() /**< Unlock critical section in CO_errorReport() or CO_errorReset() */ #define CO_LOCK_OD() /**< Lock critical section when accessing Object Dictionary */ #define CO_UNLOCK_OD() /**< Unock critical section when accessing Object Dictionary */ /** @} */ /** * @name Syncronisation functions * syncronisation for message buffer for communication between CAN receive and * message processing threads. * * If receive function runs inside IRQ, no further synchronsiation is needed. * Otherwise, some kind of synchronsiation has to be included. The following * example uses GCC builtin memory barrier __sync_synchronize(). A comprehensive * list can be found here: https://gist.github.com/leo-yuriev/ba186a6bf5cf3a27bae7 * \code{.c} #define CANrxMemoryBarrier() {__sync_synchronize();} * \endcode * @{ */ /** Memory barrier */ #define CANrxMemoryBarrier() /** Check if new message has arrived */ #define IS_CANrxNew(rxNew) ((uintptr_t)rxNew) /** Set new message flag */ #define SET_CANrxNew(rxNew) {CANrxMemoryBarrier(); rxNew = (void*)1L;} /** Clear new message flag */ #define CLEAR_CANrxNew(rxNew) {CANrxMemoryBarrier(); rxNew = (void*)0L;} /** @} */ /** * @defgroup CO_dataTypes Data types * @{ * * According to Misra C */ /* int8_t to uint64_t are defined in stdint.h */ typedef unsigned char bool_t; /**< bool_t */ typedef float float32_t; /**< float32_t */ typedef long double float64_t; /**< float64_t */ typedef char char_t; /**< char_t */ typedef unsigned char oChar_t; /**< oChar_t */ typedef unsigned char domain_t; /**< domain_t */ /** @} */ /** * CAN receive message structure as aligned in CAN module. It is different in * different microcontrollers. It usually contains other variables. */ typedef struct{ /** CAN identifier. It must be read through CO_CANrxMsg_readIdent() function. */ uint32_t ident; uint8_t DLC ; /**< Length of CAN message */ uint8_t data[8]; /**< 8 data bytes */ }CO_CANrxMsg_t; /** * Received message object */ typedef struct{ uint16_t ident; /**< Standard CAN Identifier (bits 0..10) + RTR (bit 11) */ uint16_t mask; /**< Standard Identifier mask with same alignment as ident */ void *object; /**< From CO_CANrxBufferInit() */ void (*pFunct)(void *object, const CO_CANrxMsg_t *message); /**< From CO_CANrxBufferInit() */ }CO_CANrx_t; /** * Transmit message object. */ typedef struct{ uint32_t ident; /**< CAN identifier as aligned in CAN module */ uint8_t DLC ; /**< Length of CAN message. (DLC may also be part of ident) */ uint8_t data[8]; /**< 8 data bytes */ volatile bool_t bufferFull; /**< True if previous message is still in buffer */ /** Synchronous PDO messages has this flag set. It prevents them to be sent outside the synchronous window */ volatile bool_t syncFlag; }CO_CANtx_t; /** * CAN module object. It may be different in different microcontrollers. */ typedef struct{ void *CANdriverState; /**< From CO_CANmodule_init() */ CO_CANrx_t *rxArray; /**< From CO_CANmodule_init() */ uint16_t rxSize; /**< From CO_CANmodule_init() */ CO_CANtx_t *txArray; /**< From CO_CANmodule_init() */ uint16_t txSize; /**< From CO_CANmodule_init() */ volatile bool_t CANnormal; /**< CAN module is in normal mode */ /** Value different than zero indicates, that CAN module hardware filters * are used for CAN reception. If there is not enough hardware filters, * they won't be used. In this case will be *all* received CAN messages * processed by software. */ volatile bool_t useCANrxFilters; /** If flag is true, then message in transmitt buffer is synchronous PDO * message, which will be aborted, if CO_clearPendingSyncPDOs() function * will be called by application. This may be necessary if Synchronous * window time was expired. */ volatile bool_t bufferInhibitFlag; /** Equal to 1, when the first transmitted message (bootup message) is in CAN TX buffers */ volatile bool_t firstCANtxMessage; /** Number of messages in transmit buffer, which are waiting to be copied to the CAN module */ volatile uint16_t CANtxCount; uint32_t errOld; /**< Previous state of CAN errors */ void *em; /**< Emergency object */ }CO_CANmodule_t; /** * Receives and transmits CAN messages. * * Function must be called directly from high priority CAN interrupt. * * @param CANmodule This object. */ void CO_CANinterrupt(CO_CANmodule_t *CANmodule); #ifdef __cplusplus } #endif /* __cplusplus */ /** @} */ #endif /* CO_DRIVER_TARGET_H */