diff options
Diffstat (limited to 'c-user/config/intro.rst')
| -rw-r--r-- | c-user/config/intro.rst | 43 |
1 files changed, 0 insertions, 43 deletions
diff --git a/c-user/config/intro.rst b/c-user/config/intro.rst index 4c2f715..04ec996 100644 --- a/c-user/config/intro.rst +++ b/c-user/config/intro.rst @@ -3,49 +3,6 @@ .. Copyright (C) 2012 Gedare Bloom .. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR) -Introduction -============ - -RTEMS must be configured for an application. This configuration encompasses a -variety of information including the length of each clock tick, the maximum -number of each information RTEMS object that can be created, the application -initialization tasks, the task scheduling algorithm to be used, and the device -drivers in the application. - -Although this information is contained in data structures that are used by -RTEMS at system initialization time, the data structures themselves must not be -generated by hand. RTEMS provides a set of macros system which provides a -simple standard mechanism to automate the generation of these structures. - -.. index:: confdefs.h -.. index:: <rtems/confdefs.h> - -The RTEMS header file ``<rtems/confdefs.h>`` is at the core of the automatic -generation of system configuration. It is based on the idea of setting macros -which define configuration parameters of interest to the application and -defaulting or calculating all others. This variety of macros can automatically -produce all of the configuration data required for an RTEMS application. - -.. sidebar: Trivia: - - The term ``confdefs`` is shorthand for a *Configuration Defaults*. - -As a general rule, application developers only specify values for the -configuration parameters of interest to them. They define what resources or -features they require. In most cases, when a parameter is not specified, it -defaults to zero (0) instances, a standards compliant value, or disabled as -appropriate. For example, by default there will be 256 task priority levels but -this can be lowered by the application. This number of priority levels is -required to be compliant with the RTEID/ORKID standards upon which the Classic -API is based. There are similar cases where the default is selected to be -compliant with the POSIX standard. - -For each configuration parameter in the configuration tables, the macro -corresponding to that field is discussed. The RTEMS Maintainers expect that all -systems can be easily configured using the ``<rtems/confdefs.h>`` mechanism and -that using this mechanism will avoid internal RTEMS configuration changes -impacting applications. - Default Value Selection Philosophy ================================== |