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3e729b2b1c
The period argument of a k_timer needs an offset of one tick from the value computed in user code (because periods get reset from within the ISR, see the comment above this code for an explanation). When the computed tick value was 1, it would become 0. This is actually perfectly correct as a k_timeout_t to be passed to z_add_timeout(). BUT: to k_timer's API, K_NO_WAIT means "never" (i.e. the same as K_FOREVER) and not "as soon as possible", so the period timer would not be reset. This is sort of a wart, but it's the way the API has been specified forever. The upshot is that for the case of calling k_timer_start() with a minimal period argument (i.e. one that produces "one tick"), the period would be ignored and the timer would act like a one shot. Fix the clamp so it can't produce K_NO_WAIT. This also adds a filter for absolute timeouts, which (while that's sort of a pathological usage) were getting that one tick offset when it wasn't appropriate. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
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<a href="https://www.zephyrproject.org">
<p align="center">
<img src="doc/images/Zephyr-Project.png">
</p>
</a>
<a href="https://bestpractices.coreinfrastructure.org/projects/74"><img
src="https://bestpractices.coreinfrastructure.org/projects/74/badge"></a>
<img
src="https://api.shippable.com/projects/58ffb2b8baa5e307002e1d79/badge?branch=master">
The Zephyr Project is a scalable real-time operating system (RTOS) supporting
multiple hardware architectures, optimized for resource constrained devices,
and built with security in mind.
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.
The Zephyr kernel supports multiple architectures, including ARM Cortex-M,
Intel x86, ARC, Nios II, Tensilica Xtensa, and RISC-V, and a large number of
`supported boards`_.
.. below included in doc/introduction/introduction.rst
.. start_include_here
Getting Started
***************
Welcome to Zephyr! See the `Introduction to Zephyr`_ for a high-level overview,
and the documentation's `Getting Started Guide`_ to start developing.
Community Support
*****************
Community support is provided via mailing lists and Slack; see the Resources
below for details.
.. _project-resources:
Resources
*********
Here's a quick summary of resources to help you find your way around:
* **Help**: `Asking for Help Tips`_
* **Documentation**: http://docs.zephyrproject.org (`Getting Started Guide`_)
* **Source Code**: https://github.com/zephyrproject-rtos/zephyr is the main
repository; https://elixir.bootlin.com/zephyr/latest/source contains a
searchable index
* **Releases**: https://github.com/zephyrproject-rtos/zephyr/releases
* **Samples and example code**: see `Sample and Demo Code Examples`_
* **Mailing Lists**: users@lists.zephyrproject.org and
devel@lists.zephyrproject.org are the main user and developer mailing lists,
respectively. You can join the developer's list and search its archives at
`Zephyr Development mailing list`_. The other `Zephyr mailing list
subgroups`_ have their own archives and sign-up pages.
* **Nightly CI Build Status**: https://lists.zephyrproject.org/g/builds
The builds@lists.zephyrproject.org mailing list archives the CI
(shippable) nightly build results.
* **Chat**: Zephyr's Slack workspace is https://zephyrproject.slack.com. Use
this `Slack Invite`_ to register.
* **Contributing**: see the `Contribution Guide`_
* **Wiki**: `Zephyr GitHub wiki`_
* **Issues**: https://github.com/zephyrproject-rtos/zephyr/issues
* **Security Issues**: Email vulnerabilities@zephyrproject.org to report
security issues; also see our `Security`_ documentation. Security issues are
tracked separately at https://zephyrprojectsec.atlassian.net.
* **Zephyr Project Website**: https://zephyrproject.org
.. _Slack Invite: https://tinyurl.com/y5glwylp
.. _supported boards: http://docs.zephyrproject.org/latest/boards/index.html
.. _Zephyr Documentation: http://docs.zephyrproject.org
.. _Introduction to Zephyr: http://docs.zephyrproject.org/latest/introduction/index.html
.. _Getting Started Guide: http://docs.zephyrproject.org/latest/getting_started/index.html
.. _Contribution Guide: http://docs.zephyrproject.org/latest/contribute/index.html
.. _Zephyr GitHub wiki: https://github.com/zephyrproject-rtos/zephyr/wiki
.. _Zephyr Development mailing list: https://lists.zephyrproject.org/g/devel
.. _Zephyr mailing list subgroups: https://lists.zephyrproject.org/g/main/subgroups
.. _Sample and Demo Code Examples: http://docs.zephyrproject.org/latest/samples/index.html
.. _Security: http://docs.zephyrproject.org/latest/security/index.html
.. _Asking for Help Tips: https://docs.zephyrproject.org/latest/guides/getting-help.html