zephyr

History

Sebastian Bøe 55ee53ce91 cmake: Prepend 'cmake_minimum_required()' into 'app' build scripts Prepend the text 'cmake_minimum_required(VERSION 3.8.2)' into the application and test build scripts. Modern versions of CMake will spam users with a deprecation warning when the toplevel CMakeLists.txt does not specify a CMake version. This is documented in bug #8355. To resolve this we include a cmake_minimum_required() line into the toplevel build scripts. Additionally, cmake_minimum_required is invoked from within boilerplate.cmake. The highest version will be enforced. This patch allows us to afterwards change CMake policy CMP000 from OLD to NEW which in turn finally rids us of the verbose warning. The extra boilerplate is considered more acceptable than the verbosity of the CMP0000 policy. Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>		2018-08-15 04:06:50 -07:00
..
src	samples: console: add print statements for user	2018-07-13 08:48:40 -04:00
CMakeLists.txt	cmake: Prepend 'cmake_minimum_required()' into 'app' build scripts	2018-08-15 04:06:50 -07:00
README.rst	…
prj.conf	subsys: console: Factor out fifo-based console input abstraction	2018-06-20 15:59:12 -04:00
sample.yaml	…

README.rst

.. _console_getchar_sample:

console_getchar() Sample Application
####################################

Overview
********

This example shows how to use :cpp:func:`console_getchar()` function.
Similar to the well-known ANSI C getchar() function,
:cpp:func:`console_getchar()` either returns the next available input
character or blocks waiting for one. Using this function, it should be
fairly easy to port existing ANSI C, POSIX, or Linux applications which
process console input character by character. The sample also allows to
see key/character codes as returned by the function.

If you are interested in line by line console input, see
:ref:`console_getline_sample`.


Requirements
************

UART console is required to run this simple.


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

The easiest way to run this sample is using QEMU:

.. zephyr-app-commands::
   :zephyr-app: samples/subsys/console/getchar
   :host-os: unix
   :board: qemu_x86
   :goals: run
   :compact:

Now start pressing keys on a keyboard, and they will be printed both as
hex values and in character form. Be sure to press Enter, Up/Down, etc.
key to check what control characters are produced for them.