zephyr/samples/drivers/spi_flash
Keith Packard 0b90fd5adf samples, tests, boards: Switch main return type from void to int
As both C and C++ standards require applications running under an OS to
return 'int', adapt that for Zephyr to align with those standard. This also
eliminates errors when building with clang when not using -ffreestanding,
and reduces the need for compiler flags to silence warnings for both clang
and gcc.

Most of these changes were automated using coccinelle with the following
script:

@@
@@
- void
+ int
main(...) {
	...
-	return;
+	return 0;
	...
}

Approximately 40 files had to be edited by hand as coccinelle was unable to
fix them.

Signed-off-by: Keith Packard <keithp@keithp.com>
2023-04-14 07:49:41 +09:00
..
boards drivers: spi: Microchip XEC QMSPI-LDMA fix spi buffer usage 2023-04-11 16:57:56 +02:00
src samples, tests, boards: Switch main return type from void to int 2023-04-14 07:49:41 +09:00
CMakeLists.txt cmake: increase minimal required version to 3.20.0 2021-08-20 09:47:34 +02:00
prj.conf
README.rst samples: spi_flash: add README 2020-08-27 12:39:43 -04:00
sample.yaml yamllint: indentation: fix files in samples/ 2023-01-04 14:23:53 +01:00

.. _spi-nor-sample:

JEDEC SPI-NOR Sample
####################

Overview
********

This sample demonstrates using the flash API on a SPI NOR serial flash
memory device.  While trivial it is an example of direct access and
allows confirmation that the flash is working and that automatic power
savings is correctly implemented.

Building and Running
********************

The application will build only for a target that has a :ref:`devicetree
<dt-guide>` entry with ``jedec,spi-nor`` as a compatible.

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

Sample Output
=============

.. code-block:: console

   *** Booting Zephyr OS build zephyr-v2.3.0-2142-gca01d2e1d748  ***

   JEDEC QSPI-NOR SPI flash testing
   ==========================

   Test 1: Flash erase
   Flash erase succeeded!

   Test 2: Flash write
   Attempting to write 4 bytes
   Data read matches data written. Good!