55 lines
1.4 KiB
ReStructuredText
55 lines
1.4 KiB
ReStructuredText
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.. _spi-bitbang-sample:
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SPI-Bitbang Sample
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####################
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Overview
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********
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This sample demonstrates using the bitbang SPI driver. The bitbang driver can
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be useful for devices which use a non multiple of 8 word size, for example some
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LCDs which have an extra cmd/data bit.
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This sample loops through some different spi transfer configurations.
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Building and Running
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********************
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The application will build only for a target that has a :ref:`devicetree
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<dt-guide>` entry with :dtcompatible:`zephyr,spi-bitbang` as a compatible.
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You can connect the MISO and MOSI pins with a wire to provide a basic loopback
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test for receive data.
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.. zephyr-app-commands::
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:zephyr-app: samples/drivers/spi_bitbang
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:board: nrf52840dk_nrf52840
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:goals: build flash
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:compact:
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Sample Output
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=============
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.. code-block:: console
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*** Booting Zephyr OS build zephyr-v2.6.0-2939-g1882b95b42e2 ***
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basic_write_9bit_words; ret: 0
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wrote 0101 00ff 00a5 0000 0102
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9bit_loopback_partial; ret: 0
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tx (i) : 0101 0102
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tx (ii) : 0003 0004 0105
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rx (ii) : 0003 0004 0105
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basic_write_9bit_words; ret: 0
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wrote 0101 00ff 00a5 0000 0102
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9bit_loopback_partial; ret: 0
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tx (i) : 0101 0102
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tx (ii) : 0003 0004 0105
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rx (ii) : 0003 0004 0105
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basic_write_9bit_words; ret: 0
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wrote 0101 00ff 00a5 0000 0102
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9bit_loopback_partial; ret: 0
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tx (i) : 0101 0102
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tx (ii) : 0003 0004 0105
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rx (ii) : 0003 0004 0105
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