zephyr

History

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
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src	samples, tests, boards: Switch main return type from void to int	2023-04-14 07:49:41 +09:00
CMakeLists.txt
prj.conf
README.rst
sample.yaml

README.rst

.. _uart_sample:

UART Driver Sample
##################

Overview
********

This sample demonstrates how to use the UART serial driver with a simple
echo bot. It reads data from the console and echoes the characters back after
an end of line (return key) is received.

The polling API is used for sending data and the interrupt-driven API
for receiving, so that in theory the thread could do something else
while waiting for incoming data.

By default, the UART peripheral that is normally used for the Zephyr shell
is used, so that almost every board should be supported.

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

Build and flash the sample as follows, changing ``nrf52840dk_nrf52840`` for
your board:

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

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

.. code-block:: console

    Hello! I\'m your echo bot.
    Tell me something and press enter:
    # Type e.g. "Hi there!" and hit enter!
    Echo: Hi there!