35 lines
876 B
Python
35 lines
876 B
Python
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from micropython import const
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from supervisor import ticks_ms
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_TICKS_PERIOD = const(1 << 29)
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_TICKS_MAX = const(_TICKS_PERIOD - 1)
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_TICKS_HALFPERIOD = const(_TICKS_PERIOD // 2)
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def ticks_diff(new: int, start: int) -> int:
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diff = (new - start) & _TICKS_MAX
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diff = ((diff + _TICKS_HALFPERIOD) & _TICKS_MAX) - _TICKS_HALFPERIOD
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return diff
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def ticks_add(ticks: int, delta: int) -> int:
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return (ticks + delta) % _TICKS_PERIOD
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def check_deadline(new: int, start: int, ms: int) -> int:
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return ticks_diff(new, start) < ms
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class PeriodicTimer:
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def __init__(self, period: int):
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self.period = period
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self.last_tick = ticks_ms()
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def tick(self) -> bool:
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now = ticks_ms()
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if ticks_diff(now, self.last_tick) >= self.period:
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self.last_tick = now
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return True
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else:
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return False
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