2020-03-14 02:02:31 +08:00
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.. _kscan_api:
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2019-10-08 04:48:45 +08:00
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KSCAN
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#####
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Overview
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********
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The kscan driver (keyboard scan matrix) is used for detecting a key press in a
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connected matrix keyboard or any device with buttons such as joysticks.
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Typically, matrix keyboards are implemented using a two-dimensional
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configuration in order to sense several keys. This allows interfacing to
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many keys through fewer physical pins. Keyboard matrix
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drivers read the rows while applying power through the columns one at a time
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with the purpose of detecting key events.
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There is no correlation between the physical and electrical layout of keys.
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For, example, the physical layout may be one array of 16 or fewer keys, which
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may be electrically connected to a 4 x 4 array. In addition, key values are
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defined by a keymap provided by the keyboard manufacturer.
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Configuration Options
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*********************
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Related configuration options:
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2022-02-08 00:27:43 +08:00
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* :kconfig:option:`CONFIG_KSCAN`
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2019-10-08 04:48:45 +08:00
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API Reference
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*************
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.. doxygengroup:: kscan_interface
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