/** * \file * * \brief ARM functions for busy-wait delay loops * * Copyright (c) 2013-2015 Atmel Corporation. All rights reserved. * * \asf_license_start * * \page License * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * 3. The name of Atmel may not be used to endorse or promote products derived * from this software without specific prior written permission. * * 4. This software may only be redistributed and used in connection with an * Atmel microcontroller product. * * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * \asf_license_stop * */ /* * Support and FAQ: visit Atmel Support */ #ifndef CYCLE_COUNTER_H_INCLUDED #define CYCLE_COUNTER_H_INCLUDED #include #include #ifdef __cplusplus extern "C" { #endif /** * @def F_CPU * @brief MCU Clock Frequency (Hertz) */ #ifndef F_CPU # define F_CPU system_gclk_gen_get_hz(0) #endif /** * @name Convenience functions for busy-wait delay loops * * @def delay_cycles * @brief Delay program execution for a specified number of CPU cycles. * @param n number of CPU cycles to wait * * @def cpu_delay_ms * @brief Delay program execution for a specified number of milliseconds. * @param delay number of milliseconds to wait * @param f_cpu CPU frequency in Hertz * * @def cpu_delay_us * @brief Delay program execution for a specified number of microseconds. * @param delay number of microseconds to wait * @param f_cpu CPU frequency in Hertz * * @def cpu_ms_2_cy * @brief Convert milli-seconds into CPU cycles. * @param ms number of milliseconds * @param f_cpu CPU frequency in Hertz * @return the converted number of CPU cycles * * @def cpu_us_2_cy * @brief Convert micro-seconds into CPU cycles. * @param ms number of microseconds * @param f_cpu CPU frequency in Hertz * @return the converted number of CPU cycles * * @{ */ /** * \brief Delay loop to delay n number of cycles * * \note The function runs in internal RAM so that flash wait states * will not affect the delay time. * * \param n Number of cycles */ void portable_delay_cycles(unsigned long n); #define cpu_ms_2_cy(ms, f_cpu) \ (((uint64_t)(ms) * (f_cpu) + (uint64_t)(7e3-1ul)) / (uint64_t)7e3) #define cpu_us_2_cy(us, f_cpu) \ (((uint64_t)(us) * (f_cpu) + (uint64_t)(7e6-1ul)) / (uint64_t)7e6) #define delay_cycles portable_delay_cycles #define cpu_delay_s(delay) delay_cycles(cpu_ms_2_cy(1000 * delay, F_CPU)) #define cpu_delay_ms(delay) delay_cycles(cpu_ms_2_cy(delay, F_CPU)) #define cpu_delay_us(delay) delay_cycles(cpu_us_2_cy(delay, F_CPU)) //! @} #ifdef __cplusplus } #endif #endif /* CYCLE_COUNTER_H_INCLUDED */