mirror of https://github.com/ArduPilot/ardupilot
46 lines
948 B
C
46 lines
948 B
C
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#ifndef _STOPWATCH_H
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#define _STOPWATCH_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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extern uint32_t us_ticks;
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#define DEMCR_TRCENA 0x01000000
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/* Core Debug registers */
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#define DEMCR (*((volatile uint32_t *)0xE000EDFC))
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#define DWT_CTRL (*(volatile uint32_t *)0xe0001000)
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#define CYCCNTENA (1<<0)
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#define DWT_CYCCNT ((volatile uint32_t *)0xE0001004)
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#define CPU_CYCLES *DWT_CYCCNT
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void stopwatch_init(void);
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void stopwatch_delay_us(uint32_t us);
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static inline void stopwatch_reset(void)
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{
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/* enable DWT access */
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DEMCR |= DEMCR_TRCENA;
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*DWT_CYCCNT = 0;
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/* enable the CPU cycle counter */
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DWT_CTRL |= CYCCNTENA;
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}
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static inline uint32_t stopwatch_getticks()
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{
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return CPU_CYCLES;
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}
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#ifdef __cplusplus
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}
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#endif
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#endif
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/*----------------------------------------------------------------------------
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* end of file
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*---------------------------------------------------------------------------*/
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