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Timer.h
1 /* mbed Microcontroller Library
2  * Copyright (c) 2006-2019 ARM Limited
3  * SPDX-License-Identifier: Apache-2.0
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 #ifndef MBED_TIMER_H
18 #define MBED_TIMER_H
19 
20 #include "platform/platform.h"
21 #include "hal/ticker_api.h"
22 #include "platform/NonCopyable.h"
23 
24 namespace mbed {
25 /**
26  * \defgroup drivers_Timer Timer class
27  * \ingroup drivers-public-api-ticker
28  * @{
29  */
30 
31 /** A general purpose timer
32  *
33  * @note Synchronization level: Interrupt safe
34  *
35  * Example:
36  * @code
37  * // Count the time to toggle an LED
38  *
39  * #include "mbed.h"
40  *
41  * Timer timer;
42  * DigitalOut led(LED1);
43  * int begin, end;
44  *
45  * int main() {
46  * timer.start();
47  * begin = timer.read_us();
48  * led = !led;
49  * end = timer.read_us();
50  * printf("Toggle the led takes %d us", end - begin);
51  * }
52  * @endcode
53  */
54 class Timer : private NonCopyable<Timer> {
55 
56 public:
57  Timer();
58  Timer(const ticker_data_t *data);
59  ~Timer();
60 
61  /** Start the timer
62  */
63  void start();
64 
65  /** Stop the timer
66  */
67  void stop();
68 
69  /** Reset the timer to 0.
70  *
71  * If it was already running, it will continue
72  */
73  void reset();
74 
75  /** Get the time passed in seconds
76  *
77  * @returns Time passed in seconds
78  */
79  float read();
80 
81  /** Get the time passed in milliseconds
82  *
83  * @returns Time passed in milliseconds
84  */
85  int read_ms();
86 
87  /** Get the time passed in microseconds
88  *
89  * @returns Time passed in microseconds
90  */
91  int read_us();
92 
93  /** An operator shorthand for read()
94  */
95  operator float();
96 
97  /** Get in a high resolution type the time passed in microseconds.
98  * Returns a 64 bit integer.
99  */
100  us_timestamp_t read_high_resolution_us();
101 
102 #if !defined(DOXYGEN_ONLY)
103 protected:
104  us_timestamp_t slicetime();
105  int _running; // whether the timer is running
106  us_timestamp_t _start; // the start time of the latest slice
107  us_timestamp_t _time; // any accumulated time from previous slices
108  const ticker_data_t *_ticker_data;
109  bool _lock_deepsleep; // flag that indicates if deep sleep should be disabled
110 };
111 #endif
112 
113 /** @}*/
114 
115 } // namespace mbed
116 
117 #endif
us_timestamp_t
uint64_t us_timestamp_t
A us timestamp stored in a 64 bit integer.
Definition: ticker_api.h:39
ticker_data_t
Ticker&#39;s data structure.
Definition: ticker_api.h:93
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