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docs/machine.Timer: Move WiPy adhoc parts to its documentation.
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‎docs/library/machine.Timer.rst

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.. currentmodule:: machine
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class Timer -- control internal timers
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class Timer -- control hardware timers
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======================================
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.. only:: port_wipy
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Timers can be used for a great variety of tasks, calling a function periodically,
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counting events, and generating a PWM signal are among the most common use cases.
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Each timer consists of two 16-bit channels and this channels can be tied together to
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form one 32-bit timer. The operating mode needs to be configured per timer, but then
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the period (or the frequency) can be independently configured on each channel.
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By using the callback method, the timer event can call a Python function.
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Example usage to toggle an LED at a fixed frequency::
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from machine import Timer
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from machine import Pin
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led = Pin('GP16', mode=Pin.OUT) # enable GP16 as output to drive the LED
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tim = Timer(3) # create a timer object using timer 3
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tim.init(mode=Timer.PERIODIC) # initialize it in periodic mode
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tim_ch = tim.channel(Timer.A, freq=5) # configure channel A at a frequency of 5Hz
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tim_ch.irq(handler=lambda t:led.toggle(), trigger=Timer.TIMEOUT) # toggle a LED on every cycle of the timer
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Example using named function for the callback::
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from machine import Timer
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from machine import Pin
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tim = Timer(1, mode=Timer.PERIODIC, width=32)
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tim_a = tim.channel(Timer.A | Timer.B, freq=1) # 1 Hz frequency requires a 32 bit timer
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led = Pin('GP16', mode=Pin.OUT) # enable GP16 as output to drive the LED
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def tick(timer): # we will receive the timer object when being called
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global led
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led.toggle() # toggle the LED
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tim_a.irq(handler=tick, trigger=Timer.TIMEOUT) # create the interrupt
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Further examples::
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from machine import Timer
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tim1 = Timer(1, mode=Timer.ONE_SHOT) # initialize it in one shot mode
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tim2 = Timer(2, mode=Timer.PWM) # initialize it in PWM mode
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tim1_ch = tim1.channel(Timer.A, freq=10, polarity=Timer.POSITIVE) # start the event counter with a frequency of 10Hz and triggered by positive edges
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tim2_ch = tim2.channel(Timer.B, freq=10000, duty_cycle=5000) # start the PWM on channel B with a 50% duty cycle
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tim2_ch.freq(20) # set the frequency (can also get)
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tim2_ch.duty_cycle(3010) # set the duty cycle to 30.1% (can also get)
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tim2_ch.duty_cycle(3020, Timer.NEGATIVE) # set the duty cycle to 30.2% and change the polarity to negative
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tim2_ch.period(2000000) # change the period to 2 seconds
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Hardware timers deal with timing of periods and events. Timers are perhaps
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the most flexible and heterogeneous kind of hardware in MCUs and SoCs,
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differently greatly from a model to a model. MicroPython's Timer class
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defines a baseline operation of executing a callback with a given period
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(or once after some delay), and allow specific boards to define more
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non-standard behavior (which thus won't be portable to other boards).
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.. note::
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.. class:: Timer(id, ...)
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.. only:: port_wipy
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Construct a new timer object of the given id. ``id`` can take values from 0 to 3.
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Construct a new timer object of the given id. Id of -1 constructs a
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virtual timer (if supported by a board).
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Methods
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-------
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.. method:: Timer.deinit()
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Deinitialises the timer. Disables all channels and associated IRQs.
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Stops the timer, and disables the timer peripheral.
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Deinitialises the timer. Stops the timer, and disables the timer peripheral.
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.. only:: port_wipy
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- ``GP10`` on Timer 3 channel A.
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- ``GP11`` on Timer 3 channel B.
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class TimerChannel --- setup a channel for a timer
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==================================================
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.. only:: port_wipy
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Timer channels are used to generate/capture a signal using a timer.
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class TimerChannel --- setup a channel for a timer
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==================================================
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TimerChannel objects are created using the Timer.channel() method.
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Timer channels are used to generate/capture a signal using a timer.
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Methods
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-------
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TimerChannel objects are created using the Timer.channel() method.
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.. only:: port_wipy
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Methods
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-------
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.. method:: timerchannel.irq(\*, trigger, priority=1, handler=None)
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.. data:: Timer.ONE_SHOT
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.. data:: Timer.PERIODIC
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.. data:: Timer.PWM
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Selects the timer operating mode.
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.. data:: Timer.A
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.. data:: Timer.B
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Selects the timer channel. Must be ORed (``Timer.A`` | ``Timer.B``) when
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using a 32-bit timer.
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.. data:: Timer.POSITIVE
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.. data:: Timer.NEGATIVE
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Timer channel polarity selection (only relevant in PWM mode).
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.. data:: Timer.TIMEOUT
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.. data:: Timer.MATCH
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Timer channel IRQ triggers.
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Timer operating mode.

‎docs/wipy/quickref.rst

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@@ -44,7 +44,8 @@ See :ref:`machine.Pin <machine.Pin>`. ::
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Timers
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------
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See :ref:`machine.Timer <machine.Timer>` and :ref:`machine.Pin <machine.Pin>`. ::
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See :ref:`machine.Timer <machine.Timer>` and :ref:`machine.Pin <machine.Pin>`.
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Timer ``id``'s take values from 0 to 3.::
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from machine import Timer
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from machine import Pin

‎docs/wipy/tutorial/index.rst

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repl.rst
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blynk.rst
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wlan.rst
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timer.rst
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reset.rst

‎docs/wipy/tutorial/timer.rst

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Hardware timers
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===============
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Timers can be used for a great variety of tasks, calling a function periodically,
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counting events, and generating a PWM signal are among the most common use cases.
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Each timer consists of two 16-bit channels and this channels can be tied together to
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form one 32-bit timer. The operating mode needs to be configured per timer, but then
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the period (or the frequency) can be independently configured on each channel.
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By using the callback method, the timer event can call a Python function.
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Example usage to toggle an LED at a fixed frequency::
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from machine import Timer
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from machine import Pin
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led = Pin('GP16', mode=Pin.OUT) # enable GP16 as output to drive the LED
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tim = Timer(3) # create a timer object using timer 3
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tim.init(mode=Timer.PERIODIC) # initialize it in periodic mode
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tim_ch = tim.channel(Timer.A, freq=5) # configure channel A at a frequency of 5Hz
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tim_ch.irq(handler=lambda t:led.toggle(), trigger=Timer.TIMEOUT) # toggle a LED on every cycle of the timer
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Example using named function for the callback::
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from machine import Timer
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from machine import Pin
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tim = Timer(1, mode=Timer.PERIODIC, width=32)
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tim_a = tim.channel(Timer.A | Timer.B, freq=1) # 1 Hz frequency requires a 32 bit timer
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led = Pin('GP16', mode=Pin.OUT) # enable GP16 as output to drive the LED
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def tick(timer): # we will receive the timer object when being called
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global led
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led.toggle() # toggle the LED
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tim_a.irq(handler=tick, trigger=Timer.TIMEOUT) # create the interrupt
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Further examples::
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from machine import Timer
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tim1 = Timer(1, mode=Timer.ONE_SHOT) # initialize it in one shot mode
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tim2 = Timer(2, mode=Timer.PWM) # initialize it in PWM mode
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tim1_ch = tim1.channel(Timer.A, freq=10, polarity=Timer.POSITIVE) # start the event counter with a frequency of 10Hz and triggered by positive edges
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tim2_ch = tim2.channel(Timer.B, freq=10000, duty_cycle=5000) # start the PWM on channel B with a 50% duty cycle
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tim2_ch.freq(20) # set the frequency (can also get)
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tim2_ch.duty_cycle(3010) # set the duty cycle to 30.1% (can also get)
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tim2_ch.duty_cycle(3020, Timer.NEGATIVE) # set the duty cycle to 30.2% and change the polarity to negative
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tim2_ch.period(2000000) # change the period to 2 seconds
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Additional constants for Timer class
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------------------------------------
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.. data:: Timer.PWM
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PWM timer operating mode.
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.. data:: Timer.A
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.. data:: Timer.B
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Selects the timer channel. Must be ORed (``Timer.A`` | ``Timer.B``) when
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using a 32-bit timer.
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.. data:: Timer.POSITIVE
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.. data:: Timer.NEGATIVE
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Timer channel polarity selection (only relevant in PWM mode).
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.. data:: Timer.TIMEOUT
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.. data:: Timer.MATCH
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Timer channel IRQ triggers.

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