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
|
.. _lang-board-values:
Board-Specific Constants
========================
There are a number of board-specific values: constants or variables
which are different depending on which LeafLabs board you have.
This page lists and documents the board-specific values. You should
use these when appropriate in your own programs. This will help make
it easier to share your code with other people who have different
boards. Some example usages are given :ref:`below
<lang-board-values-examples>`.
.. contents:: Contents
:local:
Constants
---------
- ``CLOCK_SPEED_MHZ``: Clock speed of your board, in megahertz
(MHz). This is the same as ``CYCLES_PER_MICROSECOND``.
- ``CLOCK_SPEED_HZ``: Clock speed of your board, in hertz (Hz). This
is the same as ``CLOCK_SPEED_MHZ * 1000000``.
- ``CYCLES_PER_MICROSECOND``: Number of CPU cycles per microsecond on
your board.
.. _lang-board-values-but:
- ``BOARD_BUTTON_PIN``: Pin connected to the built-in button (labeled
"BUT" on your board's silkscreen).
.. _lang-board-values-led:
- ``BOARD_LED_PIN``: Pin connected to the built-in LED.
- ``BOARD_NR_GPIO_PINS``: Total number of :ref:`GPIO pins <gpio>` that
are broken out to headers. Some of these might already be connected
to external hardware (like the built-in LED and button). To find
out if a pin is in use, see :ref:`boardUsesPin()
<lang-boardusespin>` (and also :ref:`boardUsedPins
<lang-board-values-used-pins>`).
.. _lang-board-values-nr-pwm-pins:
- ``BOARD_NR_PWM_PINS``: Total *number* of GPIO pins that can be used
for :ref:`PWM <pwm>`. The actual *pins* that can do PWM are in the
:ref:`boardPWMPins <lang-board-values-pwm-pins>` array.
.. _lang-board-values-nr-adc-pins:
- ``BOARD_NR_ADC_PINS``: Total number of GPIO pins that can be used
for :ref:`analog-to-digital conversion <adc>`. The actual pins that
can do ADC conversion are in the :ref:`boardADCPins
<lang-board-values-adc-pins>` array.
.. _lang-board-values-nr-used-pins:
- ``BOARD_NR_USED_PINS``: Total number of GPIO pins that are already
connected to some external hardware (like a built-in LED) on the
board. The actual pins that that are already used are in the
:ref:`boardUsedPins <lang-board-values-used-pins>` array. To see if
a pin is already in use, use the :ref:`boardUsesPin()
<lang-boardusespin>` function.
.. _lang-board-values-usart:
- USART (serial port) related constants:
* ``BOARD_USART1_TX_PIN``, ``BOARD_USART2_TX_PIN``, ``BOARD_USART3_TX_PIN``:
TX pins for the 3 USARTS.
* ``BOARD_USART1_RX_PIN``, ``BOARD_USART2_RX_PIN``, ``BOARD_USART3_RX_PIN``:
RX pins for the 3 USARTS.
* ``BOARD_UART4_TX_PIN``, ``BOARD_UART5_TX_PIN``: TX pins for
UARTs 4 and 5 (high-density boards like Maple Native only).
* ``BOARD_UART4_RX_PIN``, ``BOARD_UART5_RX_PIN``: RX pins for
UARTs 4 and 5 (high-density boards like Maple Native only).
* ``BOARD_NR_USARTS``: Number of serial ports on the board. This
number includes UARTs 4 and 5 if they are available.
.. _lang-board-values-pwm-pins:
.. _lang-board-values-adc-pins:
.. _lang-board-values-used-pins:
Pin Arrays
----------
Some :ref:`arrays <lang-array>` of pin numbers are available which you
can use to find out certain important information about a given pin.
.. TODO add links to the board-specific hardware information on what
.. are in these arrays
- ``boardPWMPins``: Pin numbers of each pin capable of :ref:`PWM
<pwm>` output, using :ref:`pwmWrite() <lang-pwmwrite>`. The total
number of these pins is :ref:`BOARD_NR_PWM_PINS
<lang-board-values-nr-pwm-pins>`.
- ``boardADCPins``: Pin numbers of each pin capable of :ref:`ADC
<adc>` conversion, using :ref:`analogRead() <lang-analogread>`. The
total number of these pins is :ref:`BOARD_NR_ADC_PINS
<lang-board-values-nr-adc-pins>`.
- ``boardUsedPins``: Pin numbers of each pin that, by default, is used
for some special purpose by the board. The total number of these
pins is :ref:`BOARD_NR_USED_PINS <lang-board-values-nr-used-pins>`.
To check if a pin is used for a special purpose, use
:ref:`boardUsesPin() <lang-boardusespin>`.
.. _lang-board-values-examples:
Examples
--------
:ref:`BOARD_LED_PIN <lang-board-values-led>` On the Maple, the
built-in LED is connected to pin 13. On the Maple Mini, however, it
is connected to pin 33. You can write a "blinky" program that works
on all LeafLabs boards using ``BOARD_LED_PIN`` and :ref:`toggleLED()
<lang-toggleled>`::
void setup() {
pinMode(BOARD_LED_PIN, OUTPUT);
}
void loop() {
toggleLED();
delay(100);
}
:ref:`BOARD_BUTTON_PIN <lang-board-values-but>`: Similarly, you can
write a single program that prints a message whenever the button is
pressed which will work on all LeafLabs boards using
``BOARD_BUTTON_PIN`` and :ref:`isButtonPressed()
<lang-isbuttonpressed>`::
void setup() {
pinMode(BOARD_BUTTON_PIN, INPUT);
}
void loop() {
if (isButtonPressed()) {
SerialUSB.println("You pressed the button!");
}
}
See Also
--------
- :ref:`lang-boardusespin`
- :ref:`lang-isbuttonpressed`
- :ref:`lang-waitforbuttonpress`
- :ref:`lang-pinmode`
- :ref:`lang-toggleled`
- :ref:`lang-analogread`
- :ref:`lang-pwmwrite`
|
