1 /*
2  * @brief Common stopwatch support
3  *
4  * @note
5  * Copyright(C) NXP Semiconductors, 2013
6  * All rights reserved.
7  *
8  * @par
9  * Software that is described herein is for illustrative purposes only
10  * which provides customers with programming information regarding the
11  * LPC products.  This software is supplied "AS IS" without any warranties of
12  * any kind, and NXP Semiconductors and its licensor disclaim any and
13  * all warranties, express or implied, including all implied warranties of
14  * merchantability, fitness for a particular purpose and non-infringement of
15  * intellectual property rights.  NXP Semiconductors assumes no responsibility
16  * or liability for the use of the software, conveys no license or rights under any
17  * patent, copyright, mask work right, or any other intellectual property rights in
18  * or to any products. NXP Semiconductors reserves the right to make changes
19  * in the software without notification. NXP Semiconductors also makes no
20  * representation or warranty that such application will be suitable for the
21  * specified use without further testing or modification.
22  *
23  * @par
24  * Permission to use, copy, modify, and distribute this software and its
25  * documentation is hereby granted, under NXP Semiconductors' and its
26  * licensor's relevant copyrights in the software, without fee, provided that it
27  * is used in conjunction with NXP Semiconductors microcontrollers.  This
28  * copyright, permission, and disclaimer notice must appear in all copies of
29  * this code.
30  */
31 
32 #ifndef __STOPWATCH_H_
33 #define __STOPWATCH_H_
34 
35 #include "cmsis.h"
36 
37 /** @defgroup Stop_Watch CHIP: Stopwatch primitives.
38  * @ingroup CHIP_Common
39  * @{
40  */
41 
42 /**
43  * @brief	Initialize stopwatch
44  * @return	Nothing
45  */
46 void StopWatch_Init(void);
47 
48 /**
49  * @brief	Start a stopwatch
50  * @return	Current cycle count
51  */
52 uint32_t StopWatch_Start(void);
53 
54 /**
55  * @brief      Returns number of ticks elapsed since stopwatch was started
56  * @param      startTime	: Time returned by StopWatch_Start().
57  * @return     Number of ticks elapsed since stopwatch was started
58  */
StopWatch_Elapsed(uint32_t startTime)59 STATIC INLINE uint32_t StopWatch_Elapsed(uint32_t startTime)
60 {
61 	return StopWatch_Start() - startTime;
62 }
63 
64 /**
65  * @brief	Returns number of ticks per second of the stopwatch timer
66  * @return	Number of ticks per second of the stopwatch timer
67  */
68 uint32_t StopWatch_TicksPerSecond(void);
69 
70 /**
71  * @brief	Converts from stopwatch ticks to mS.
72  * @param	ticks	: Duration in ticks to convert to mS.
73  * @return	Number of mS in given number of ticks
74  */
75 uint32_t StopWatch_TicksToMs(uint32_t ticks);
76 
77 /**
78  * @brief	Converts from stopwatch ticks to uS.
79  * @param	ticks	: Duration in ticks to convert to uS.
80  * @return	Number of uS in given number of ticks
81  */
82 uint32_t StopWatch_TicksToUs(uint32_t ticks);
83 
84 /**
85  * @brief	Converts from mS to stopwatch ticks.
86  * @param	mS	: Duration in mS to convert to ticks.
87  * @return	Number of ticks in given number of mS
88  */
89 uint32_t StopWatch_MsToTicks(uint32_t mS);
90 
91 /**
92  * @brief	Converts from uS to stopwatch ticks.
93  * @param	uS	: Duration in uS to convert to ticks.
94  * @return	Number of ticks in given number of uS
95  */
96 uint32_t StopWatch_UsToTicks(uint32_t uS);
97 
98 /**
99  * @brief	Delays the given number of ticks using stopwatch primitives
100  * @param	ticks	: Number of ticks to delay
101  * @return	Nothing
102  */
StopWatch_DelayTicks(uint32_t ticks)103 STATIC INLINE void StopWatch_DelayTicks(uint32_t ticks)
104 {
105 	uint32_t startTime = StopWatch_Start();
106 	while (StopWatch_Elapsed(startTime) < ticks) {}
107 }
108 
109 /**
110  * @brief	Delays the given number of mS using stopwatch primitives
111  * @param	mS	: Number of mS to delay
112  * @return	Nothing
113  */
StopWatch_DelayMs(uint32_t mS)114 STATIC INLINE void StopWatch_DelayMs(uint32_t mS)
115 {
116 	uint32_t ticks = StopWatch_MsToTicks(mS);
117 	uint32_t startTime = StopWatch_Start();
118 	while (StopWatch_Elapsed(startTime) < ticks) {}
119 }
120 
121 /**
122  * @brief	Delays the given number of uS using stopwatch primitives
123  * @param	uS	: Number of uS to delay
124  * @return	Nothing
125  */
StopWatch_DelayUs(uint32_t uS)126 STATIC INLINE void StopWatch_DelayUs(uint32_t uS)
127 {
128 	uint32_t ticks = StopWatch_UsToTicks(uS);
129 	uint32_t startTime = StopWatch_Start();
130 	while (StopWatch_Elapsed(startTime) < ticks) {}
131 }
132 
133 /**
134  * @}
135  */
136 
137 #endif /* __STOPWATCH_H_ */
138