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author | danicampora <daniel@wipy.io> | 2015-10-14 12:32:01 +0200 |
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committer | danicampora <daniel@wipy.io> | 2015-10-17 23:29:04 +0200 |
commit | 4542643025c77a7272bde348b89d5039aea28d23 (patch) | |
tree | bf9fb006f46b96d2ea9ecf4aa190c4e4cc2abfc8 /docs/library/pyb.Timer.rst | |
parent | fca3308cc376f2c1c66fa3cef82e30c55c9acca2 (diff) | |
download | micropython-4542643025c77a7272bde348b89d5039aea28d23.tar.gz micropython-4542643025c77a7272bde348b89d5039aea28d23.zip |
docs: Update all WiPy docs to reflect the new API.
Diffstat (limited to 'docs/library/pyb.Timer.rst')
-rw-r--r-- | docs/library/pyb.Timer.rst | 158 |
1 files changed, 0 insertions, 158 deletions
diff --git a/docs/library/pyb.Timer.rst b/docs/library/pyb.Timer.rst index ca1d4702e5..af28fb6787 100644 --- a/docs/library/pyb.Timer.rst +++ b/docs/library/pyb.Timer.rst @@ -41,50 +41,6 @@ class Timer -- control internal timers the servo driver, and Timer 6 is used for timed ADC/DAC reading/writing. It is recommended to use the other timers in your programs. -.. only:: port_wipy - - Timers can be used for a great variety of tasks, calling a function periodically, - counting events, and generating a PWM signal are among the most common use cases. - Each timer consists of 2 16-bit channels and this channels can be tied together to - form 1 32-bit timer. The operating mode needs to be configured per timer, but then - the period (or the frequency) can be independently configured on each channel. - By using the callback method, the timer event can call a Python function. - - Example usage to toggle an LED at a fixed frequency:: - - tim = pyb.Timer(4) # create a timer object using timer 4 - tim.init(mode=Timer.PERIODIC) # initialize it in periodic mode - tim_ch = tim.channel(Timer.A, freq=2) # configure channel A at a frequency of 2Hz - tim_ch.callback(handler=lambda t:led.toggle()) # toggle a LED on every cycle of the timer - - Example using named function for the callback:: - - tim = Timer(1, mode=Timer.PERIODIC) - tim_a = tim.channel(Timer.A, freq=1000) - - led = Pin('GPIO2', af=0, mode=Pin.OUT) - - def tick(timer): # we will receive the timer object when being called - print(timer.time()) # show current timer's time value (is microseconds) - led.toggle() # toggle the LED - - tim_a.callback(handler=tick) - - Further examples:: - - tim1 = pyb.Timer(2, mode=Timer.EVENT_COUNT) # initialize it capture mode - tim2 = pyb.Timer(1, mode=Timer.PWM) # initialize it in PWM mode - tim_ch = tim1.channel(Timer.A, freq=1, polarity=Timer.POSITIVE) # start the event counter with a frequency of 1Hz and triggered by positive edges - tim_ch = tim2.channel(Timer.B, freq=10000, duty_cycle=50) # start the PWM on channel B with a 50% duty cycle - tim_ch.time() # get the current time in usec (can also be set) - tim_ch.freq(20) # set the frequency (can also get) - tim_ch.duty_cycle(30) # set the duty cycle to 30% (can also get) - tim_ch.duty_cycle(30, Timer.NEGATIVE) # set the duty cycle to 30% and change the polarity to negative - tim_ch.event_count() # get the number of captured events - tim_ch.event_time() # get the the time of the last captured event - tim_ch.period(2000000) # change the period to 2 seconds - - *Note:* Memory can't be allocated during a callback (an interrupt) and so exceptions raised within a callback don't give much information. See :func:`micropython.alloc_emergency_exception_buf` for how to get around this @@ -102,13 +58,6 @@ Constructors arguments are given, then the timer is initialised by ``init(...)``. ``id`` can be 1 to 14, excluding 3. - .. only:: port_wipy - - Construct a new timer object of the given id. If additional - arguments are given, then the timer is initialised by ``init(...)``. - ``id`` can be 1 to 4. - - Methods ------- @@ -161,30 +110,6 @@ Methods You must either specify freq or both of period and prescaler. -.. only:: port_wipy - - .. method:: timer.init(mode, \*, width=16) - - Initialise the timer. Example:: - - tim.init(Timer.PERIODIC) # periodic 16-bit timer - tim.init(Timer.ONE_SHOT, width=32) # one shot 32-bit timer - - Keyword arguments: - - - ``mode`` can be one of: - - - ``Timer.ONE_SHOT`` - The timer runs once until the configured - period of the channel expires. - - ``Timer.PERIODIC`` - The timer runs periodically at the configured - frequency of the channel. - - ``Timer.EDGE_TIME`` - Meaure the time pin level changes. - - ``Timer.EDGE_COUNT`` - Count the number of pin level changes. - - - ``width`` must be either 16 or 32 (bits). For really low frequencies <= ~1Hz - (or large periods), 32-bit timers should be used. 32-bit mode is only available - for ``ONE_SHOT`` AND ``PERIODIC`` modes. - .. method:: timer.deinit() Deinitialises the timer. @@ -280,37 +205,6 @@ Methods ch2 = timer.channel(2, pyb.Timer.PWM, pin=pyb.Pin.board.X2, pulse_width=8000) ch3 = timer.channel(3, pyb.Timer.PWM, pin=pyb.Pin.board.X3, pulse_width=16000) -.. only:: port_wipy - - .. method:: timer.channel(channel, \**, freq, period, polarity=Timer.POSITIVE, duty_cycle=0) - - If only a channel identifier passed, then a previously initialized channel - object is returned (or ``None`` if there is no previous channel). - - Othwerwise, a TimerChannel object is initialized and returned. - - The operating mode is is the one configured to the Timer object that was used to - create the channel. - - - ``channel`` if the width of the timer is 16-bit, then must be either ``TIMER.A``, ``TIMER.B``. - If the width is 32-bit then it **must be** ``TIMER.A | TIMER.B``. - - Keyword only arguments: - - - ``freq`` sets the frequency in Hz. - - ``period`` sets the period in microseconds. - - .. note:: - - Either ``freq`` or ``period`` must be given, never both. - - - ``polarity`` this is applicable for: - - - ``PWM``, defines the polarity of the duty cycle - - ``EDGE_TIME`` and ``EDGE_COUNT``, defines the polarity of the pin level change to detect. - To detect both rising and falling edges, make ``polarity=Timer.POSITIVE | Timer.NEGATIVE``. - - ``duty_cycle`` only applicable to ``PWM``. It's a percentage (0-100) - .. only:: port_pyboard .. method:: timer.counter([value]) @@ -355,32 +249,6 @@ Methods ``fun`` is passed 1 argument, the timer object. If ``fun`` is ``None`` then the callback will be disabled. -.. only:: port_wipy - - .. method:: timerchannel.callback(\**, value, priority=1, handler=None) - - The behavior of this callback is heaviliy dependent on the operating - mode of the timer channel: - - - If mode is ``Timer.PERIODIC`` the callback is executed periodically - with the configured frequency or period. - - If mode is ``Timer.ONE_SHOT`` the callback is executed once when - the configured timer expires. - - If mode is ``Timer.EDGE_COUNT`` the callback is executed when reaching - the configured number of events (see ``value`` param below). - - If mode is ``Timer.PWM`` the callback is executed when reaching the duty - cycle value. - - The accepted params are: - - - ``priority`` level of the interrupt. Can take values in the range 1-7. - Higher values represent higher priorities. - - ``handler`` is an optional function to be called when the interrupt is triggered. - - ``value`` is **only valid** when in ``Timer.EDGE_COUNT`` mode and is used to set - the number of edge events that will trigger the interrupt. - - Returns a callback object. - .. only:: port_pyboard .. method:: timerchannel.capture([value]) @@ -411,29 +279,3 @@ Methods for which the pulse is active. The value can be an integer or floating-point number for more accuracy. For example, a value of 25 gives a duty cycle of 25%. - -.. only:: port_wipy - - .. method:: timerchannel.freq([value]) - - Get or set the timer channel frequency (in Hz). - - .. method:: timerchannel.period([value]) - - Get or set the timer channel period (in microseconds). - - .. method:: timerchannel.time([value]) - - Get or set the timer channel current **time** value (in microseconds). - - .. method:: timerchannel.event_count() - - Get the number of edge events counted. - - .. method:: timerchannel.event_time() - - Get the time of ocurrance of the last event. - - .. method:: timerchannel.duty_cycle([value]) - - Get or set the duty cycle of the PWM signal (in the range of 0-100). |