1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
.. _machine.Pin:
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
digital logic level. For analog control of a pin, see the ADC class.
Usage Model:
.. only:: port_wipy
Board pins are identified by their string id::
from machine import Pin
g = machine.Pin('GP9', mode=Pin.OUT, pull=None, drive=Pin.MED_POWER, alt=-1)
You can also configure the Pin to generate interrupts. For instance::
from machine import Pin
def pincb(pin):
print(pin.id())
pin_int = Pin('GP10', mode=Pin.IN, pull=Pin.PULL_DOWN)
pin_int.irq(mode=Pin.IRQ_RISING, handler=pincb)
# the callback can be triggered manually
pin_int.irq()()
# to disable the callback
pin_int.irq().disable()
Now every time a falling edge is seen on the gpio pin, the callback will be
executed. Caution: mechanical push buttons have "bounce" and pushing or
releasing a switch will often generate multiple edges.
See: http://www.eng.utah.edu/~cs5780/debouncing.pdf for a detailed
explanation, along with various techniques for debouncing.
All pin objects go through the pin mapper to come up with one of the
gpio pins.
Constructors
------------
.. class:: machine.Pin(id, ...)
Create a new Pin object associated with the id. If additional arguments are given,
they are used to initialise the pin. See :meth:`pin.init`.
Methods
-------
.. only:: port_wipy
.. method:: pin.init(mode, pull, \*, drive, alt)
Initialise the pin:
- ``mode`` can be one of:
- ``Pin.IN`` - input pin.
- ``Pin.OUT`` - output pin in push-pull mode.
- ``Pin.OPEN_DRAIN`` - output pin in open-drain mode.
- ``Pin.ALT`` - pin mapped to an alternate function.
- ``Pin.ALT_OPEN_DRAIN`` - pin mapped to an alternate function in open-drain mode.
- ``pull`` can be one of:
- ``None`` - no pull up or down resistor.
- ``Pin.PULL_UP`` - pull up resistor enabled.
- ``Pin.PULL_DOWN`` - pull down resitor enabled.
- ``drive`` can be one of:
- ``Pin.LOW_POWER`` - 2mA drive capability.
- ``Pin.MED_POWER`` - 4mA drive capability.
- ``Pin.HIGH_POWER`` - 6mA drive capability.
- ``alt`` is the number of the alternate function. Please refer to the
`pinout and alternate functions table. <https://raw.githubusercontent.com/wipy/wipy/master/docs/PinOUT.png>`_
for the specific alternate functions that each pin supports.
Returns: ``None``.
.. method:: pin.id()
Get the pin id.
.. method:: pin.value([value])
Get or set the digital logic level of the pin:
- With no argument, return 0 or 1 depending on the logic level of the pin.
- With ``value`` given, set the logic level of the pin. ``value`` can be
anything that converts to a boolean. If it converts to ``True``, the pin
is set high, otherwise it is set low.
.. method:: pin.alt_list()
Returns a list of the alternate functions supported by the pin. List items are
a tuple of the form: ``('ALT_FUN_NAME', ALT_FUN_INDEX)``
.. only:: port_wipy
.. method:: pin([value])
Pin objects are callable. The call method provides a (fast) shortcut to set and get the value of the pin.
See **pin.value** for more details.
.. method:: pin.toggle()
Toggle the value of the pin.
.. method:: pin.mode([mode])
Get or set the pin mode.
.. method:: pin.pull([pull])
Get or set the pin pull.
.. method:: pin.drive([drive])
Get or set the pin drive strength.
.. method:: pin.irq(\*, trigger, priority=1, handler=None, wake=None)
Create a callback to be triggered when the input level at the pin changes.
- ``trigger`` configures the pin level which can generate an interrupt. Possible values are:
- ``Pin.IRQ_FALLING`` interrupt on falling edge.
- ``Pin.IRQ_RISING`` interrupt on rising edge.
- ``Pin.IRQ_LOW_LEVEL`` interrupt on low level.
- ``Pin.IRQ_HIGH_LEVEL`` interrupt on high level.
The values can be *ORed* together, for instance mode=Pin.IRQ_FALLING | Pin.IRQ_RISING
- ``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 new characters arrive.
- ``wakes`` selects the power mode in which this interrupt can wake up the
board. Please note:
- If ``wake_from=machine.Sleep.ACTIVE`` any pin can wake the board.
- If ``wake_from=machine.Sleep.SUSPENDED`` pins ``GP2``, ``GP4``, ``GP10``,
``GP11``, GP17`` or ``GP24`` can wake the board. Note that only 1
of this pins can be enabled as a wake source at the same time, so, only
the last enabled pin as a ``machine.Sleep.SUSPENDED`` wake source will have effect.
- If ``wake_from=machine.Sleep.SUSPENDED`` pins ``GP2``, ``GP4``, ``GP10``,
``GP11``, ``GP17`` and ``GP24`` can wake the board. In this case all of the
6 pins can be enabled as a ``machine.Sleep.HIBERNATE`` wake source at the same time.
- Values can be ORed to make a pin generate interrupts in more than one power
mode.
Returns a callback object.
Attributes
----------
.. class:: Pin.board
Contains all ``Pin`` objects supported by the board. Examples::
Pin.board.GP25
led = Pin(Pin.board.GP25, mode=Pin.OUT)
Pin.board.GP2.alt_list()
Constants
---------
.. only:: port_wipy
.. data:: Pin.IN
.. data:: Pin.OUT
.. data:: Pin.OPEN_DRAIN
.. data:: Pin.ALT
.. data:: Pin.ALT_OPEN_DRAIN
Selects the pin mode.
.. data:: Pin.PULL_UP
.. data:: Pin.PULL_DOWN
Selectes the wether there's pull up/down resistor.
.. data:: Pin.LOW_POWER
.. data:: Pin.MED_POWER
.. data:: Pin.HIGH_POWER
Selects the drive strength.
.. data:: Pin.IRQ_FALLING
.. data:: Pin.IRQ_RISING
.. data:: Pin.IRQ_LOW_LEVEL
.. data:: Pin.IRQ_HIGH_LEVEL
Selects the IRQ trigger type.
|
