doc: Update intro with ble mesh and kernel features

Expand introduction about Zephyr with additional details.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This commit is contained in:
Anas Nashif 2018-09-20 06:47:37 -05:00
commit 780c1c28ee

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@ -4,11 +4,12 @@ Introducing Zephyr
##################
The Zephyr OS is based on a small-footprint kernel designed for use on
resource-constrained systems: from simple embedded environmental sensors and LED
wearables to sophisticated smart watches and IoT wireless gateways.
resource-constrained and embedded systems: from simple embedded environmental
sensors and LED wearables to sophisticated embedded controllers, smart
watches, and IoT wireless applications.
The Zephyr kernel supports multiple architectures, including ARM Cortex-M, Intel
x86, ARC, NIOS II, Tensilica Xtensa, and RISC-V. The full list of supported
x86, ARC, NIOS II, Tensilica Xtensa and RISC-V 32. The full list of supported
boards can be found :ref:`here <boards>`.
Licensing
@ -29,8 +30,43 @@ as described in :ref:`Zephyr_Licensing`.
Distinguishing Features
***********************
The Zephyr kernel offers a number of features that distinguish it from other
small-footprint OSes:
Zephyr offers a large and evergrowing number of features including:
**Extensive suite of Kernel services**
Zephyr offers a number of familiar services for development:
* *Multi-threading Services* for cooperative, priority-based,
non-preemptive, and preemptive threads with optional round robin
time-slicing. Includes POSIX pthreads compatible API support.
* *Interrupt Services* for compile-time registration of interrupt handlers.
* *Memory Allocation Services* for dynamic allocation and freeing of
fixed-size or variable-size memory blocks.
* *Inter-thread Synchronization Services* for binary semaphores,
counting semaphores, and mutex semaphores.
* *Inter-thread Data Passing Services* for basic message queues, enhanced
message queues, and byte streams.
* *Power Management Services* such as tickless idle and an advanced idling
infrastructure.
**Multiple Scheduling Algorithms**
Zephyr provides a comprehensive set of thread scheduling choices:
* Cooperative and Preemptive Scheduling
* Earliest Deadline First (EDF)
* Meta IRQ scheduling implementing "interrupt bottom half" or "tasklet"
behavior
* Timeslicing: Enables time slicing between preemptible threads of equal
priority
* Multiple queueing strategies:
* Simple linked-list ready queue
* Red/black tree ready queue
* Traditional multi-queue ready queue
**Highly configurable / Modular for flexibility**
Allows an application to incorporate *only* the capabilities it needs as it
@ -90,6 +126,12 @@ small-footprint OSes:
* Verified with multiple popular controllers
* Highly configurable
Mesh Support:
* Relay, Friend Node, Low-Power Node (LPN) and GATT Proxy features
* Both Provisioning bearers supported (PB-ADV & PB-GATT)
* Highly configurable, fitting in devices with at least 16k RAM
**Native Linux, macOS, and Windows Development**
A command-line CMake build environment runs on popular developer OS
systems. A native POSIX port, lets you build and run Zephyr as a native
@ -123,28 +165,6 @@ small-footprint OSes:
Supports running Zephyr as a Linux application with support for various
subsystems and networking.
**Extensive suite of Kernel services**
Zephyr offers a number of familiar services for development:
* *Multi-threading Services* for cooperative, priority-based,
non-preemptive, and preemptive threads with optional round robin
time-slicing. Includes pthreads compatible API support.
* *Interrupt Services* for compile-time registration of interrupt handlers.
* *Memory Allocation Services* for dynamic allocation and freeing of
fixed-size or variable-size memory blocks.
* *Inter-thread Synchronization Services* for binary semaphores,
counting semaphores, and mutex semaphores.
* *Inter-thread Data Passing Services* for basic message queues, enhanced
message queues, and byte streams.
* *Power Management Services* such as tickless idle and an advanced idling
infrastructure.
.. include:: ../../README.rst
:start-after: start_include_here