/**
* @defgroup stdcan StdCan Library
* @code #include <drivers/can/stdcan.h> @endcode
*
* @brief High level functions for bus communication and standard node behaviour.
*
* This library provides a higher level interface to the CAN bus than the raw driver/BIOS
* interface, as well as functions for easy implementation of required node behaviour.
*
* It implements receive and transmit FIFOs of configurable lengths, Application Startup
* message at init, and Heartbeat transmission.
*
* @author Andreas Fritiofson
* @date 2007-10-24
*/
/**@{*/
#ifndef STDCAN_H_
#define STDCAN_H_
#include <config.h>
#include <drivers/can/canid.h>
#include <inttypes.h>
#ifndef STDCAN_FILTER
#define STDCAN_FILTER 0
#endif
#ifndef STDCAN_RX_QUEUE_SIZE
#define STDCAN_RX_QUEUE_SIZE 8
#endif
#ifndef STDCAN_TX_QUEUE_SIZE
#define STDCAN_TX_QUEUE_SIZE 1
#endif
/**
* @brief Return values.
*
* Most StdCan functions return one of these values.
*/
typedef enum {
StdCan_Ret_OK, /**< Operation completed successfully. */
StdCan_Ret_Full, /**< Failed to send because transmit queue was full. */
StdCan_Ret_Empty, /**< Failed to read because receive queue was empty. */
StdCan_Ret_Fail, /**< General error. */
StdCan_Ret_DataErr /**< Malformed data. */
} StdCan_Ret_t;
/**
* @brief Message structure.
*
* Stores a CAN message frame. Flags that are unsupported have been
* excluded (RTR and standard id).
*/
typedef struct {
#ifdef MODULE_APPLICATION
union {
uint32_t Id; /**< CAN extended ID (29 bits). */
struct {
uint8_t Command;
uint8_t ModuleId;
uint8_t ModuleType;
uint8_t ClassAndDirection;
} Header;
};
#else
unsigned long Id; /**< CAN extended ID (29 bits). */
#endif
char Length; /**< Data length [0,8]. */
unsigned char Data[8]; /**< Data array. Only the first \c Length elements are valid. */
#if (STDCAN_FILTER)
unsigned char Match; /**< Filter id that matched this message. */
#endif
} StdCan_Msg_t;
#define StdCan_Ret_class(Header) (uint8_t)((Header.ClassAndDirection >> 1) & 0x0F)
#define StdCan_Set_class(Header, CLASS) Header.ClassAndDirection &= 0x01; Header.ClassAndDirection |= (CLASS << 1);
#define StdCan_Ret_direction(Header) (uint8_t)(Header.ClassAndDirection & 0x01)
#define StdCan_Set_direction(Header, DIR) Header.ClassAndDirection &= 0xfe; Header.ClassAndDirection |= DIR;
#define NODE_HW_ID_BYTE3 (uint8_t)((BIOS_GetHwId()>>24)&0xff)
#define NODE_HW_ID_BYTE2 (uint8_t)((BIOS_GetHwId()>>16)&0xff)
#define NODE_HW_ID_BYTE1 (uint8_t)((BIOS_GetHwId()>>8)&0xff)
#define NODE_HW_ID_BYTE0 (uint8_t)((BIOS_GetHwId())&0xff)
/**
* @brief Node descriptor.
*
* Describes the node and the application running on it.
* TODO: Discuss the purpose and layout of Node_Desc_t.
*/
typedef struct {
unsigned short Type; /**< Application type (documented elsewhere). */
unsigned short Version; /**< Application version number (application defined). */
unsigned char Id; /**< Node ID. */
} Node_Desc_t;
/**
* @brief Initialize StdCan.
*
* Initializes the StdCan and lower layers and sends an Application Startup
* Message.
*
* @param node_desc
* Pointer to node descriptor, containing information about the type and
* version of the application that should be announced in startup and
* heartbeat messages.
*/
#ifdef MODULE_APPLICATION
StdCan_Ret_t StdCan_Init(void);
#else
StdCan_Ret_t StdCan_Init(Node_Desc_t* node_desc);
#endif
/**
* @brief Get a message.
*
* Retrieves a message from the receive queue.
*
* @param[out] msg
* Pointer to message stucture to be filled with the next message from
* the queue.
*/
StdCan_Ret_t StdCan_Get(StdCan_Msg_t* msg);
/**
* @brief Send a message.
*
* Puts a message on the transmit queue.
*
* @param[in] msg
* Pointer to message to send.
*/
StdCan_Ret_t StdCan_Put(StdCan_Msg_t* msg);
/**
* @brief Send a Heartbeat.
*
* Puts a Heartbeat message on the transmit queue. Takes an \c uint8_t and
* returns \c void in order to be able to use it as a \c Timer callback
* directly, i.e.
* @code
* Timer_SetTimeout(APP_HEARTBEAT_TIMER, STDCAN_HEARTBEAT_PERIOD, TimerTypeFreeRunning, StdCan_SendHeartbeat);
* @endcode
* If the transmit queue is full this function will silently fail.
*
* @param n
* Dummy value.
*/
void StdCan_SendHeartbeat(uint8_t n);
/**
* @brief Enable a message acceptance filter.
*
* Allows incoming messages to be accepted or rejected by matching their id.
* Message is accepted if @code (message_id ^ id) & mask @endcode is zero for any
* of the active filters.
*
* @param filter
* Filter slot to activate (filter < STDCAN_NUM_FILTERS).
* @param id
* Match if id matches the message id in all bit locations that are
* not masked.
* @param mask
* Each bit specifies if the corresponding id bit must match (mask[n] = 1)
* or is Don't Care (mask[n] = 0).
*/
StdCan_Ret_t StdCan_EnableFilter(unsigned char filter, unsigned long id, unsigned long mask);
/**
* @brief Disable a message acceptance filter.
*
* Disables a filter (marks it at not matching any messages).
*
* @param filter
* Filter slot to disable (filter < STDCAN_NUM_FILTERS).
*/
StdCan_Ret_t StdCan_DisableFilter(unsigned char filter);
/**@}*/
#endif /*STDCAN_H_*/