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class Timer – Measure Time and Set
Alarms
Timers can be used for a great variety of tasks, like measuring time spans or being notified
that a specific interval has elapsed.
These two concepts are grouped into two different subclasses:
Chrono
: used to measure time spans.
Alarm
: to get interrupted after a specific interval.
You can create as many of these objects as needed.
Constructors
class Timer.Chrono()
Create a chronometer object.
class Timer.Alarm(handler=None, s, * , ms, us, arg=None, periodic=False)
Create an Alarm object.
handler
: will be called after the interval has elapsed. If set to
None
, the alarm will be
disabled after creation.
arg
: an optional argument can be passed to the callback handler function. If
None
is
specified, the function will receive the object that triggered the alarm.
s, ms, us
: the interval can be specified in seconds (float), miliseconds (integer) or
microseconds (integer). Only one at a time can be specified.
periodic
: an alarm can be set to trigger repeatedly by setting this parameter to
True
.
Methods
Timer.sleep_us()
Delay for a given number of microseconds, should be positive or 0 (for speed, the condition
is not enforced). Internally it uses the same timer as the other elements of the
Timer
class.
It compensates for the calling overhead, so for example, 100us should be really close to
100us. For times bigger than 10,000us it releases the GIL to let other threads run, so
exactitude is not guaranteed for delays longer than that.
5.2.1.10 Timer
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