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Jukka Laitinen 101ff2c2bb arch/imx9: Add bidirectional dshot driver using i.MX9 FlexIO
Create a bidirectional dshot lower-half driver, using the flexio block.

This driver enables use of DShot protocol for Electronic Speed Controllers
(ESCs) typically used in drone motor control.

Eight channels of DShot per flexio block are supported in:

- Normal mode in all DShot speeds, with telemetry request (uart response
  needs to be handled outside of this driver)
- Bidirectional mode in all DShot speeds, with telemetry request & response
- Configurable to use either independent TX timers for each channel, or to
  use a common TX timer for all channels to synchronize the output
- For bidirectional RX, each channel always uses an own timer.

In normal mode, the driver operates without any interrupts.

In bidirectional mode, the driver reconfigures the FlexIO timers (as needed)
and shifters from TX to RX in the interrupt handler, and reads out the
raw response packet.

Signed-off-by: Jukka Laitinen <jukka.laitinen@tii.ae>
2026-04-30 12:24:47 +08:00
.github .github: use ntfc test cases from Apache repo 2026-04-24 19:56:22 +08:00
arch arch/imx9: Add bidirectional dshot driver using i.MX9 FlexIO 2026-04-30 12:24:47 +08:00
audio include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
binfmt include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
boards boards/qemu-i486: Add support to QEMU VGA framebuffer 2026-04-30 11:56:49 +08:00
cmake cmake: Moved the creation of the nxtmpdir folder to the root CMake file 2026-04-22 06:22:36 +08:00
crypto include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
Documentation doc/qemu-i486: Add documentation about qemu-i486:vga_fb 2026-04-30 11:56:49 +08:00
drivers drivers/timers: Add common include files, definitions and upper-half for DSHOT 2026-04-30 12:24:47 +08:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs fs/inode: add optional manual FD backtrace control via task group flag 2026-04-28 09:53:27 +02:00
graphics include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
include drivers/timers: Add common include files, definitions and upper-half for DSHOT 2026-04-30 12:24:47 +08:00
libs include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
mm include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
net net/nat: Let ICMP echo id zero be a valid NAT id. 2026-04-28 00:38:34 -03:00
openamp openamp: Fix Make style 2026-03-23 18:16:46 -04:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched clock_settime: don't block when up_rtc_settime is called 2026-04-28 15:15:05 -04:00
syscall syscall: fcntl param3 type to uintptr_t 2026-04-27 12:01:55 -03:00
tools ci/testlist/risc-v-02.dat: Added boards build with CMake 2026-04-22 06:22:36 +08:00
video include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
wireless include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
.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 tools/Unix.mk: fix Untracked files defconfig.tmp-e on macOS 2026-04-15 17:10:22 +08:00
.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 Donny Jiuzhu 2026-02-25 10:17:40 +01:00
CMakeLists.txt cmake: Moved the creation of the nxtmpdir folder to the root CMake file 2026-04-22 06:22:36 +08:00
CONTRIBUTING.md docs: Fix typos, formatting, and numbering in README.md and CONTRIBUTING.md. 2026-03-23 12:05:24 +01:00
INVIOLABLES.md
Kconfig tools/stackusage.py: use toolchain binaries instead of Python libraries 2026-03-17 11:26:44 -03:00
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 docs: Fix typos, formatting, and numbering in README.md and CONTRIBUTING.md. 2026-03-23 12:05:24 +01:00
ReleaseNotes Documentation: move ReleaseNotes 2023-09-26 20:41:00 +08:00

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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.