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/******************************************************************************
* The MIT License
*
* Copyright (c) 2010 Perry Hung.
* Copyright (c) 2011 LeafLabs, LLC.
*
* 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 THE AUTHORS OR COPYRIGHT HOLDERS
* 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.
*****************************************************************************/
/**
* @file libmaple/include/libmaple/delay.h
* @brief Delay implementation
*/
#ifndef _LIBMAPLE_DELAY_H_
#define _LIBMAPLE_DELAY_H_
#ifdef __cplusplus
extern "C" {
#endif
#include <libmaple/libmaple_types.h>
#include <libmaple/stm32.h>
/**
* @brief Delay the given number of microseconds.
*
* @param us Number of microseconds to delay.
*/
static inline void delay_us(uint32 us) {
us *= STM32_DELAY_US_MULT;
/* fudge for function call overhead */
us--;
asm volatile(" mov r0, %[us] \n\t"
"1: subs r0, #1 \n\t"
" bhi 1b \n\t"
:
: [us] "r" (us)
: "r0");
}
#ifdef __cplusplus
}
#endif
#endif
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