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Diffstat (limited to 'docs/library/pyb.Pin.rst')
| -rw-r--r-- | docs/library/pyb.Pin.rst | 57 |
1 files changed, 55 insertions, 2 deletions
diff --git a/docs/library/pyb.Pin.rst b/docs/library/pyb.Pin.rst index ad47d587ae..576268172d 100644 --- a/docs/library/pyb.Pin.rst +++ b/docs/library/pyb.Pin.rst @@ -1,5 +1,5 @@ -class Pin --- control I/O pins -============================== +class Pin -- control I/O pins +============================= A pin is the basic object to control I/O pins. It has methods to set the mode of the pin (input, output, etc) and methods to get and set the @@ -206,3 +206,56 @@ Constants .. data:: Pin.PULL_UP enable the pull-up resistor on the pin + + +class PinAF -- Pin Alternate Functions +====================================== + +A Pin represents a physical pin on the microcprocessor. Each pin +can have a variety of functions (GPIO, I2C SDA, etc). Each PinAF +object represents a particular function for a pin. + +Usage Model:: + + x3 = pyb.Pin.board.X3 + x3_af = x3.af_list() + +x3_af will now contain an array of PinAF objects which are availble on +pin X3. + +For the pyboard, x3_af would contain: + [Pin.AF1_TIM2, Pin.AF2_TIM5, Pin.AF3_TIM9, Pin.AF7_USART2] + +Normally, each peripheral would configure the af automatically, but sometimes +the same function is available on multiple pins, and having more control +is desired. + +To configure X3 to expose TIM2_CH3, you could use:: + + pin = pyb.Pin(pyb.Pin.board.X3, mode=pyb.Pin.AF_PP, af=pyb.Pin.AF1_TIM2) + +or:: + + pin = pyb.Pin(pyb.Pin.board.X3, mode=pyb.Pin.AF_PP, af=1) + + +Methods +------- + +.. method:: pinaf.__str__() + + Return a string describing the alternate function. + +.. method:: pinaf.index() + + Return the alternate function index. + +.. method:: pinaf.name() + + Return the name of the alternate function. + +.. method:: pinaf.reg() + + Return the base register associated with the peripheral assigned to this + alternate function. For example, if the alternate function were TIM2_CH3 + this would return stm.TIM2 |