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/**
* @file
* @brief Asynchronous delay routines based on the SysTick Timer.
*/
/* ****************************************************************************
* Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of Maxim Integrated
* Products, Inc. shall not be used except as stated in the Maxim Integrated
* Products, Inc. Branding Policy.
*
* The mere transfer of this software does not imply any licenses
* of trade secrets, proprietary technology, copyrights, patents,
* trademarks, maskwork rights, or any other form of intellectual
* property whatsoever. Maxim Integrated Products, Inc. retains all
* ownership rights.
*
* $Date: 2018-11-05 09:52:05 -0600 (Mon, 05 Nov 2018) $
* $Revision: 38934 $
*
*************************************************************************** */
/* Define to prevent redundant inclusion */
#ifndef _DELAY_H_
#define _DELAY_H_
/**
* @defgroup MXC_delay Delay Utility Functions
* @ingroup devicelibs
* @brief Asynchronous delay routines based on the SysTick Timer
* @{
*/
/***** Definitions *****/
/**
* Macro used to specify a microsecond timing parameter in seconds.
* \code
* x = SEC(3) // 3 seconds -> x = 3,000,000
* \endcode
*/
#define MXC_DELAY_SEC(s) (((unsigned long)s) * 1000000UL)
/**
* Macro used to specify a microsecond timing parameter in milliseconds.
* \code
* x = MSEC(3) // 3ms -> x = 3,000
* \endcode
*/
#define MXC_DELAY_MSEC(ms) (ms * 1000UL)
/**
* Macro used to specify a microsecond timing parameter.
* \code
* x = USEC(3) // 3us -> x = 3
* \endcode
*/
#define MXC_DELAY_USEC(us) (us)
/***** Function Prototypes *****/
/**
* @brief Blocks and delays for the specified number of microseconds.
* @details Uses the SysTick to create the requested delay. If the SysTick is
* running, the current settings will be used. If the SysTick is not
* running, it will be started.
* @param us microseconds to delay
* @return #E_NO_ERROR if no errors, @ref MXC_Error_Codes "error" if unsuccessful.
*/
int mxc_delay(unsigned long us);
/**
* @brief Starts a non-blocking delay for the specified number of
* microseconds.
* @details Uses the SysTick to time the requested delay. If the SysTick is
* running, the current settings will be used. If the SysTick is not
* running, it will be started.
* @note mxc_delay_handler() must be called from the SysTick interrupt service
* routine or at a rate greater than the SysTick overflow rate.
* @param us microseconds to delay
* @return #E_NO_ERROR if no errors, #E_BUSY if currently servicing another
* delay request.
*/
int mxc_delay_start(unsigned long us);
/**
* @brief Returns the status of a non-blocking delay request
* @pre Start the asynchronous delay by calling mxc_delay_start().
* @return #E_BUSY until the requested delay time has expired.
*/
int mxc_delay_check(void);
/**
* @brief Stops an asynchronous delay previously started.
* @pre Start the asynchronous delay by calling mxc_delay_start().
*/
void mxc_delay_stop(void);
/**
* @brief Processes the delay interrupt.
* @details This function must be called from the SysTick IRQ or polled at a
* rate greater than the SysTick overflow rate.
*/
void mxc_delay_handler(void);
/**@} end of group MXC_delay */
#endif /* _DELAY_H_ */