sci.h

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/*************************************************************************/
#ifndef SCI_H
#define SCI_H
 
/*!***************************************************************************
 * @defgroup    sci SCI: Systems Communication Interface
 * @ingroup     explorer_app
 *
 * @brief       Systems Communication Interface
 *
 * @details     The systems communication interface module provides a high
 *              level protocol for information exchange between several systems.
 *              Basically it is a two point interface containing a single master
 *              and a single slave device.
 *
 *              The protocol is a frame based hardware interface. Each data
 *              frame consists of a dedicate start and stop byte that determines
 *              the bounds of the frame. After the start byte, the first byte is
 *              considered to be the command identifier that specifies the
 *              following data. After that, an arbitrary number of data bytes
 *              can follow. In order to provide the full range per byte, the
 *              start and stop bytes are escaped and inverted by escape bytes.
 *              Thus the data bytes can have any value. Finally, the frame is
 *              finished with an 8-bit CRC value before the stop byte is send.
 *
 *              Apart from the CRC value, that assures the correct data integrity,
 *              there are acknowledge messages sent from the device in order
 *              to verify the correct receiving and execution of the commands
 *              within the slave system. I.e. every received command will cause
 *              either an acknowledge or an not-acknowledge with a corresponding
 *              status byte that informs the master about the error cause.
 *              On the other hand, the transmitted messages do not have to be
 *              acknowledged by the master.
 *
 * @addtogroup  sci
 * @{
 *****************************************************************************/
 
#include "sci_status.h"
#include "sci_frame.h"
 
/*!***************************************************************************
 *  The SCI command type identifier byte.
 *****************************************************************************/
typedef uint8_t sci_cmd_t;
 
/*!***************************************************************************
 *  The SCI parameter type. An abstract (integer) parameter to be used in the
 *  function.
 *****************************************************************************/
typedef uint32_t sci_param_t;
 
/*!***************************************************************************
 *  The SCI data pointer type. An abstract void pointer to any data object.
 *****************************************************************************/
typedef void const * sci_data_t;
 
/*!***************************************************************************
 *  The SCI device ID type. A value of DEVICEID_DEFAULT will target the
 *  device assigned as default by the ExplorerApp. Any other value >0 up
 *  to a maximum defined by the ExplorerApp is a valid device.
 *****************************************************************************/
typedef uint8_t sci_device_t;
 
/*!***************************************************************************
 *  The Device ID of the default device (usually the first device).
 *****************************************************************************/
#define DEVICEID_DEFAULT    0
 
/*!***************************************************************************
 *  The specific Device ID of the default device (the first device).
 *****************************************************************************/
#define DEVICEID_FIRST_VALID    1
 
/*!***************************************************************************
 * @brief   Received command invocation function definition.
 *
 * @details This function pointer represents a command that is invoked whenever
 *          the corresponding data frame has been received via the SCI module.
 *
 * @param   deviceID The ID (index) of the SPI device that should process
 *          the received frame.
 * @param   frame Pointer to the received data frame.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
typedef status_t (*sci_rx_cmd_fct_t)(sci_device_t deviceID, sci_frame_t * frame);
 
/*!***************************************************************************
 * @brief   Transmitting command function definition.
 *
 * @details This function pointer represents a command that is invoked whenever
 *          the corresponding data frame will be sent via the SCI module. It
 *          contains a pointer to the data that must serialized into the data
 *          frame structure.
 *
 * @param   deviceID The ID (index) of the SPI device that should process
 *          the received frame.
 * @param   frame Pointer to the data frame that will be transmitted.
 * @param   param An optional abstract parameter to be used in the command
 *                  function.
 * @param   data An optional abstract pointer to the data to be serialize.
 *                 The pointer van be null.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
typedef status_t (*sci_tx_cmd_fct_t)(sci_device_t deviceID, sci_frame_t * frame,
        sci_param_t param, sci_data_t data);
 
/*!***************************************************************************
 * @brief   Callback function type for received SCI data frames.
 *
 * @param   frame Pointer to the received data frame.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
typedef status_t (*sci_rx_cmd_cb_t)(sci_frame_t * frame);
 
/*!***************************************************************************
 * @brief   Callback function type for SCI error.
 *
 * @param   status The corresponding error code.
 *****************************************************************************/
typedef void (*sci_error_cb_t)(status_t status);
 
/*!***************************************************************************
 * @brief   Initialize the SCI module.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_Init(void);
 
/*!***************************************************************************
 * @brief   Installs a callback routine for command received event.
 *
 * @details Installs a callback function that will be called after a command
 *          has been received successfully. This call is determined to inform
 *          about an new Rx data frame has been received and the corresponding
 *          command shall be invoked. Thus, after the callback, invoke the
 *          #SCI_InvokeRxCommand() function.
 *
 *          If no callback is set, the commands are invoked directly from the
 *          interrupt services routine. Therefore, it is highly recommended to
 *          install a callback and invoke the commands from the main thread/task.
 *
 * @warning The callback function is called from the interrupt service routine
 *          and should return within an appropriate time!
 *
 * @param   cb The callback functions to be called
 *****************************************************************************/
void SCI_SetRxCommandCallback(sci_rx_cmd_cb_t cb);
 
/*!***************************************************************************
 * @brief   Removes the previously installed callback function.
 *****************************************************************************/
void SCI_RemoveRxCommandCallback(void);
 
/*!***************************************************************************
 * @brief   Installs a callback routine for the error event.
 *
 * @details Installs a callback function that will be called after an error
 *          has occurred.
 *
 * @warning The callback function is called from the interrupt service routine
 *          and should return within an appropriate time!
 *
 * @param   cb The callback functions to be called
 *****************************************************************************/
void SCI_SetErrorCallback(sci_error_cb_t cb);
 
/*!***************************************************************************
 * @brief   Removes the previously installed callback function.
 *****************************************************************************/
void SCI_RemoveErrorCallback(void);
 
/*!***************************************************************************
 * @brief   Sends a command via the SCI module.
 *
 * @details The corresponding command function will be called in order to
 *          serialize the data from into a data frame. The frame is sent
 *          afterwards.
 *
 * @param   deviceID deviceID to which this frame belongs to.
 * @param   cmd  The command code / keyword.
 * @param   param An optional abstract parameter to be used in the command
 *                  function.
 * @param   data An optional abstract pointer to the data to be serialize.
 *                 The pointer can be null.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SendCommand(sci_device_t deviceID, sci_cmd_t cmd, sci_param_t param, sci_data_t data);
 
/*!***************************************************************************
 * @brief   Sets a Rx command function in the list of available commands.
 *
 * @details Registers the command code to the SCI module. If already set, the
 *          corresponding Rx function is replaced by the specified one. The Tx
 *          function will not be changed.
 *
 * @param   cmd The command code / keyword.
 * @param   fct The function to be called when a command is received.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SetRxCommand(sci_cmd_t cmd, sci_rx_cmd_fct_t fct);
 
/*!***************************************************************************
 * @brief   Sets Rx and post Rx command functions in the list of available commands.
 *
 * @details Registers the command code to the SCI module. If already set, the
 *          corresponding Rx function is replaced by the specified one. The Tx
 *          function will not be changed.
 *
 *          An optional post RX function can be passed that will be called
 *          after the RX command has finished. This is after the ACK has been
 *          sent and the TX line has become idle. Note that this might block
 *          the MCU for some time.
 *
 * @param   cmd The command code / keyword.
 * @param   rxfct The function to be called when a command is received.
 * @param   pfct  The function to be called when a command is received but after
 *                the ACK/NAK has been invoked.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SetPostRxCommand(sci_cmd_t cmd, sci_rx_cmd_fct_t rxfct, sci_rx_cmd_fct_t pfct);
 
/*!***************************************************************************
 * @brief   Sets a Tx command function in the list of available commands.
 *
 * @details Registers the command code to the SCIs module. If already set, the
 *          corresponding Tx function is replaced by the specified one. The Rx
 *          function will not be changed.
 *
 * @param   cmd The command code / keyword.
 * @param   txfct The function to be called when a command is sent.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SetTxCommand(sci_cmd_t cmd, sci_tx_cmd_fct_t txfct);
 
/*!***************************************************************************
 * @brief   Sets the Rx and Tx command functions in the list of available commands.
 *
 * @details Registers the command code to the SCI module. If already set, the
 *          corresponding Tx and Rx functions are replaced by the specified ones.
 *
 * @param   cmd   The command code / keyword.
 * @param   rxfct The function to be called when a command is received.
 * @param   txfct The function to be called when a command is sent.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SetRxTxCommand(sci_cmd_t cmd, sci_rx_cmd_fct_t rxfct, sci_tx_cmd_fct_t txfct);
 
/*!***************************************************************************
 * @brief   Sets the Rx and Tx command functions in the list of available commands.
 *
 * @details Registers the command code to the SCI module. If already set, the
 *          corresponding Tx and Rx functions are replaced by the specified ones.
 *
 *          An optional post RX function can be passed that will be called
 *          after the RX command has finished. This is after the ACK has been
 *          sent and the TX line has become idle. Note that this might block
 *          the MCU for some time.
 *
 * @param   cmd   The command code / keyword.
 * @param   rxfct The function to be called when a command is received.
 * @param   txfct The function to be called when a command is sent.
 * @param   pfct  The function to be called when a command is received but
 *                after the ACK/NAK has been invoked.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_SetCommand(sci_cmd_t cmd, sci_rx_cmd_fct_t rxfct,
                        sci_tx_cmd_fct_t txfct, sci_rx_cmd_fct_t pfct);
 
/*!***************************************************************************
 * @brief   Unsets a command from the list of available commands.
 *
 * @details Removes the command code from the SCI module, i.e. it deletes the
 *          corresponding Tx and Rx functions. If not set, the function returns
 *          with #ERROR_SCI_UNKNOWN_COMMAND.
 *
 * @param   cmd The command code / keyword.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_UnsetCommand(sci_cmd_t cmd);
 
/*!***************************************************************************
 * @brief   Invokes the previously received user command.
 *
 * @details Parses and executes the previously received command. To be called
 *          after Command Received Handler has been invoked.
 *
 * @param   frame The previously received SCI frame (parameter of
 *                  "RxFrameCallback") with the command code and parameter
 *                   buffer.
 *
 * @return  Returns the \link #status_t status\endlink (#STATUS_OK on success).
 *****************************************************************************/
status_t SCI_InvokeRxCommand(sci_frame_t * frame);
 
#endif // SCI_H