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hysteresis.cpp
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33 
34 /**
35  * @file hysteresis.cpp
36  *
37  * @author Julian Oes <julian@oes.ch>
38  */
39 
40 #include "hysteresis.h"
41 
42 namespace systemlib
43 {
44 
45 void
46 Hysteresis::set_hysteresis_time_from(const bool from_state, const hrt_abstime new_hysteresis_time_us)
47 {
48  if (from_state) {
49  _time_from_true_us = new_hysteresis_time_us;
50 
51  } else {
52  _time_from_false_us = new_hysteresis_time_us;
53  }
54 }
55 
56 void
57 Hysteresis::set_state_and_update(const bool new_state, const hrt_abstime &now_us)
58 {
59  if (new_state != _state) {
60  if (new_state != _requested_state) {
61  _requested_state = new_state;
63  }
64 
65  } else {
67  }
68 
69  update(now_us);
70 }
71 
72 void
74 {
75  if (_requested_state != _state) {
76 
77  const hrt_abstime elapsed = now_us - _last_time_to_change_state;
78 
79  if (_state && !_requested_state) {
80  // true -> false
81  if (elapsed >= _time_from_true_us) {
82  _state = false;
83  }
84 
85  } else if (!_state && _requested_state) {
86  // false -> true
87  if (elapsed >= _time_from_false_us) {
88  _state = true;
89  }
90  }
91  }
92 }
93 
94 } // namespace systemlib
hrt_abstime _time_from_true_us
Definition: hysteresis.h:72
void set_state_and_update(const bool new_state, const hrt_abstime &now_us)
Definition: hysteresis.cpp:57
void update(const hrt_abstime &now_us)
Definition: hysteresis.cpp:73
__BEGIN_DECLS typedef uint64_t hrt_abstime
Absolute time, in microsecond units.
Definition: drv_hrt.h:58
Hysteresis of a boolean value.
void set_hysteresis_time_from(const bool from_state, const hrt_abstime new_hysteresis_time_us)
Definition: hysteresis.cpp:46
hrt_abstime _time_from_false_us
Definition: hysteresis.h:73
hrt_abstime _last_time_to_change_state
Definition: hysteresis.h:70