SPI-Bitbang Sample

Overview

This sample demonstrates using the bitbang SPI driver. The bitbang driver can be useful for devices which use a non multiple of 8 word size, for example some LCDs which have an extra cmd/data bit.

This sample loops through some different spi transfer configurations.

Building and Running

The application will build only for a target that has a :ref:`devicetree <dt-guide>` entry with :dtcompatible:`zephyr,spi-bitbang` as a compatible.

You can connect the MISO and MOSI pins with a wire to provide a basic loopback test for receive data.

.. zephyr-app-commands::
   :zephyr-app: samples/drivers/spi_bitbang
   :board: nrf52840dk_nrf52840
   :goals: build flash
   :compact:

Sample Output

*** Booting Zephyr OS build zephyr-v2.6.0-2939-g1882b95b42e2  ***
basic_write_9bit_words; ret: 0
  wrote 0101 00ff 00a5 0000 0102
9bit_loopback_partial; ret: 0
 tx (i)  : 0101 0102
 tx (ii) : 0003 0004 0105
 rx (ii) : 0003 0004 0105
basic_write_9bit_words; ret: 0
 wrote 0101 00ff 00a5 0000 0102
9bit_loopback_partial; ret: 0
 tx (i)  : 0101 0102
 tx (ii) : 0003 0004 0105
 rx (ii) : 0003 0004 0105
basic_write_9bit_words; ret: 0
 wrote 0101 00ff 00a5 0000 0102
9bit_loopback_partial; ret: 0
 tx (i)  : 0101 0102
 tx (ii) : 0003 0004 0105
 rx (ii) : 0003 0004 0105