1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
/*
* @brief LPC8xx specific stopwatch implementation
*
* @note
* Copyright(C) NXP Semiconductors, 2013
* All rights reserved.
*
* @par
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* LPC products. This software is supplied "AS IS" without any warranties of
* any kind, and NXP Semiconductors and its licensor disclaim any and
* all warranties, express or implied, including all implied warranties of
* merchantability, fitness for a particular purpose and non-infringement of
* intellectual property rights. NXP Semiconductors assumes no responsibility
* or liability for the use of the software, conveys no license or rights under any
* patent, copyright, mask work right, or any other intellectual property rights in
* or to any products. NXP Semiconductors reserves the right to make changes
* in the software without notification. NXP Semiconductors also makes no
* representation or warranty that such application will be suitable for the
* specified use without further testing or modification.
*
* @par
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, under NXP Semiconductors' and its
* licensor's relevant copyrights in the software, without fee, provided that it
* is used in conjunction with NXP Semiconductors microcontrollers. This
* copyright, permission, and disclaimer notice must appear in all copies of
* this code.
*/
#include "chip.h"
#include "stopwatch.h"
/*****************************************************************************
* Private types/enumerations/variables
****************************************************************************/
/* Precompute these to optimize runtime */
static uint32_t ticksPerSecond;
static uint32_t ticksPerMs;
static uint32_t ticksPerUs;
/*****************************************************************************
* Public types/enumerations/variables
****************************************************************************/
/*****************************************************************************
* Private functions
****************************************************************************/
/*****************************************************************************
* Public functions
****************************************************************************/
/* Initialize stopwatch */
void StopWatch_Init(void)
{
Chip_MRT_Init();
Chip_MRT_SetMode(LPC_MRT_CH1, MRT_MODE_REPEAT);
Chip_MRT_SetInterval(LPC_MRT_CH1, 0x7ffffff | MRT_INTVAL_LOAD);
Chip_MRT_GetEnabled(LPC_MRT_CH1);
/* Pre-compute tick rate. */
ticksPerSecond = Chip_Clock_GetSystemClockRate();
ticksPerMs = ticksPerSecond / 1000;
ticksPerUs = ticksPerSecond / 1000000;
}
/* reset stopwatch */
void StopWatch_Reset(void)
{
Chip_MRT_SetInterval(LPC_MRT_CH1, 0x7ffffff | MRT_INTVAL_LOAD);
}
/* Start a stopwatch */
uint32_t StopWatch_Start(void)
{
/* Return the current timer count. */
return 0x7ffffff - Chip_MRT_GetTimer(LPC_MRT_CH1);
}
/* Returns number of ticks per second of the stopwatch timer */
uint32_t StopWatch_TicksPerSecond(void)
{
return ticksPerSecond;
}
/* Converts from stopwatch ticks to mS. */
uint32_t StopWatch_TicksToMs(uint32_t ticks)
{
return ticks / ticksPerMs;
}
/* Converts from stopwatch ticks to uS. */
uint32_t StopWatch_TicksToUs(uint32_t ticks)
{
return ticks / ticksPerUs;
}
/* Converts from mS to stopwatch ticks. */
uint32_t StopWatch_MsToTicks(uint32_t mS)
{
return mS * ticksPerMs;
}
/* Converts from uS to stopwatch ticks. */
uint32_t StopWatch_UsToTicks(uint32_t uS)
{
return uS * ticksPerUs;
}
|
