Apache NuttX is a mature, real-time embedded operating system (RTOS) https://nuttx.apache.org/
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Jukka Laitinen 191575eac1 imx9: Add proper initialization of the SD card with different bus speeds
- Change the board's sd-card speed configuration to just specify the wanted frequency
- Calculate the proper divisors in the driver
- If the sd card frequency exceeds 25 MHz, set the card to high-speed mode

This makes it easier to adjust the operating speed of the sd cards and fixes an error
where cards are being operated in standard mode at over 25MHz speeds. If the speed
is higher than 25MHz, the card needs to be set into high-speed mode.

Signed-off-by: Jukka Laitinen <jukka.laitinen@tii.ae>
2026-02-16 10:52:04 -05:00
.github docs/plantuml: Add PlantUML support to Documentation build 2026-02-15 08:47:23 +01:00
arch imx9: Add proper initialization of the SD card with different bus speeds 2026-02-16 10:52:04 -05:00
audio Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
binfmt Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
boards imx9: Add proper initialization of the SD card with different bus speeds 2026-02-16 10:52:04 -05:00
cmake cmake(bugfix):change default compile obj extension to .o 2026-01-27 20:54:26 +08:00
crypto Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
Documentation docs/pic32mz-starterkit: Migrate README.txt to RST 2026-02-15 13:28:32 +01:00
drivers Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
dummy
fs Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
graphics Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
include lzf: prevent lzf header struct optimization 2026-02-13 11:58:50 +01:00
libs Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
mm Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
net Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
openamp Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
syscall Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
tools tools: fix make host_info flag parsing and config string escaping 2026-02-05 14:23:19 +01:00
video Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
wireless Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines net/icmpv6: replace net_lock with conn_lock and conn_lock_dev 2025-12-29 09:42:18 +08:00
.codespellrc codespellrc: add ist to ignorelist 2025-10-14 17:42:01 +08:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore gitignore: add more vim swap files 2025-06-18 15:44:51 -04:00
.gitmessage docs/contributing: Add a commit message template 2025-06-03 17:33:24 +08:00
.pre-commit-config.yaml pre-commit: enable codespell checks 2025-05-05 12:34:39 +08:00
.yamllint
AUTHORS AUTHORS: add Michal Lenc 2025-12-03 08:46:33 -03:00
CMakeLists.txt boards/arm/stm32: Fix CMake build for protected mode on stm32f4discovery 2026-02-02 13:24:34 +08:00
CONTRIBUTING.md style: fix spelling in code comments and strings 2025-05-23 10:48:41 +08:00
INVIOLABLES.md
Kconfig Kconfig: Add ALLOW_CUSTOM_PERMISSIVE_COMPONENTS option 2026-01-20 02:15:19 +08:00
LICENSE style: fix spelling in code comments and strings 2025-05-23 10:48:41 +08:00
Makefile tools: migrate to SPDX identifier 2024-09-10 23:11:11 +08:00
NOTICE
README.md
ReleaseNotes

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Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).

For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.

Getting Started

First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.

Documentation

You can find the current NuttX documentation on the Documentation Page.

Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.

The old NuttX documentation is still available in the Apache wiki.

Supported Boards

NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.

Contributing

If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.

License

The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.