45 lines
1.3 KiB
ReStructuredText
45 lines
1.3 KiB
ReStructuredText
.. _button-sample:
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Button demo
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###########
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Overview
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********
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A simple button demo showcasing the use of GPIO input with interrupts.
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Requirements
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************
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The demo assumes that a push button is connected to one of GPIO lines. The
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sample code is configured to work on boards with user defined buttons and that
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have defined the SW0_* variables.
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To use this sample, you will require a board that defines the user switch in its
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header file. The :file:`board.h` must define the following variables:
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- SW0_GPIO_NAME (or DT_ALIAS_SW0_GPIOS_CONTROLLER)
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- DT_ALIAS_SW0_GPIOS_PIN
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Alternatively, this could also be done by defining 'sw0' alias in the board
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device tree description file.
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Building and Running
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********************
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This sample can be built for multiple boards, in this example we will build it
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for the nucleo_f103rb board:
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.. zephyr-app-commands::
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:zephyr-app: samples/basic/button
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:board: nucleo_f103rb
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:goals: build
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:compact:
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After startup, the program looks up a predefined GPIO device, and configures the
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pin in input mode, enabling interrupt generation on falling edge. During each
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iteration of the main loop, the state of GPIO line is monitored and printed to
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the serial console. When the input button gets pressed, the interrupt handler
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will print an information about this event along with its timestamp.
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