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authorSebastian Huber <sebastian.huber@embedded-brains.de>2018-11-16 07:14:37 +0100
committerSebastian Huber <sebastian.huber@embedded-brains.de>2018-11-21 08:08:04 +0100
commit92745a4baa1a6eee88d95cfd98e4ded0f19614b6 (patch)
tree683f59f0dcdf35e3e1cdf813d1a42a87464bdb3a
parentfdaef809d58ea959a9bdd6bcc16749000bb08279 (diff)
downloadrtems-docs-92745a4baa1a6eee88d95cfd98e4ded0f19614b6.tar.bz2
c-user: Remove 16-bit object identifiers
Close #3603.
-rw-r--r--c-user/key_concepts.rst44
1 files changed, 8 insertions, 36 deletions
diff --git a/c-user/key_concepts.rst b/c-user/key_concepts.rst
index f717a87..25f9249 100644
--- a/c-user/key_concepts.rst
+++ b/c-user/key_concepts.rst
@@ -94,19 +94,14 @@ name:
Object IDs
----------
-An object ID is a unique unsigned integer value which uniquely identifies an
-object instance. Object IDs are passed as arguments to many directives in
-RTEMS and RTEMS translates the ID to an internal object pointer. The efficient
-manipulation of object IDs is critical to the performance of RTEMS services.
-Because of this, there are two object Id formats defined. Each target
-architecture specifies which format it will use. There is a thirty-two bit
-format which is used for most of the supported architectures and supports
-multiprocessor configurations. There is also a simpler sixteen bit format
-which is appropriate for smaller target architectures and does not support
-multiprocessor configurations.
-
-Thirty-Two Object ID Format
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
+An object ID is a unique 32-bit unsigned integer value which uniquely
+identifies an object instance. Object IDs are passed as arguments to many
+directives in RTEMS and RTEMS translates the ID to an internal object pointer.
+The efficient manipulation of object IDs is critical to the performance of some
+RTEMS services.
+
+Object ID Format
+~~~~~~~~~~~~~~~~
The thirty-two bit format for an object ID is composed of four parts: API,
object class, node, and index. The data type ``rtems_id`` is used to store
@@ -129,29 +124,6 @@ sixteen bits form an identifier within a particular object type. This
identifier, called the object index, ranges in value from 1 to the maximum
number of objects configured for this object type.
-Sixteen Bit Object ID Format
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The sixteen bit format for an object ID is composed of three parts: API, object
-class, and index. The data type ``rtems_id`` is used to store object IDs.
-
-.. code-block:: c
-
- 15 11 10 8 7 0
- +---------+-------+--------------+
- | | | |
- | Class | API | Index |
- | | | |
- +---------+-------+--------------+
-
-The sixteen-bit format is designed to be as similar as possible to the
-thrity-two bit format. The differences are limited to the eliminatation of the
-node field and reduction of the index field from sixteen-bits to 8-bits. Thus
-the sixteen bit format only supports up to 255 object instances per API/Class
-combination and single processor systems. As this format is typically utilized
-by sixteen-bit processors with limited address space, this is more than enough
-object instances.
-
Object ID Description
---------------------