Apache NuttX is a mature, real-time embedded operating system (RTOS) https://nuttx.apache.org/
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wangjianyu3 8bd50d2797 boards/xtensa/esp32s3/esp32s3-xiao: re-enable nxinit, with a working console
This restores the entrypoint switch from commit
7cc6707a76 ("boards/esp32s3-xiao: switch
defconfigs to nxinit entrypoint"), reverted in 76b90e02cbe4967193
b620abcb1efb9f6b3f8f5b after a real-hardware regression report on
Seeed XIAO ESP32-S3 (board hangs, no USB console), and fixes the
actual root cause this time instead of just reverting it.

Root cause: the shared boards/xtensa/esp32s3 init.rc starts the
interactive console as a plain "sh", which, unlike nsh_main's
nsh_consolemain(), never registers/connects the CDC-ACM gadget this
board uses as its console (CONFIG_CDCACM_CONSOLE=y, no
CONFIG_DEV_CONSOLE). Restoring the previous commit's entrypoint switch
on its own is therefore not sufficient - it would just reintroduce the
same regression, so that commit is folded into this one rather than
kept as a separate, individually broken step.

Fix, using the "console" service option added to nxinit by a companion
apps change:

- init.rc: bring up the console gadget once, unconditionally, before
  any service starts, via "exec -- sercon" (apps/system/cdcacm already
  implements exactly this and depends on neither nxinit nor nsh); flag
  the "console" service with the new "console" option so its stdio is
  connected to the (now registered) gadget device.
- esp32s3-xiao's usbnsh/combo defconfigs: add CONFIG_SYSTEM_CDCACM=y so
  sercon is actually built in. Verified with "make savedefconfig"
  against both defconfigs (byte-identical, no manual edits beyond the
  generated diff).

Verified end to end on real Seeed XIAO ESP32-S3 Sense hardware
(usbnsh): after this change the board enumerates its NuttX CDC-ACM
gadget on a normal reset and boots to an interactive nsh session
spawned by nxinit ("ps" shows init_main as PID 2, parent of "sh").

Assisted-by: Kiro:claude-sonnet-5
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
2026-09-11 21:12:18 +08:00
.github tools/ci: remove obsolete testrun harness 2026-09-02 11:44:23 -03:00
arch arch/arm/am67: Mark the DDR MPU region Non-shareable. 2026-09-11 02:59:59 +08:00
audio audio: limit the buffer count guard to shared ring requests 2026-08-05 07:58:53 +02:00
binfmt libs/libc/elf, binfmt: Describe the GOT by base and size, not by index. 2026-09-08 16:31:16 -03:00
boards boards/xtensa/esp32s3/esp32s3-xiao: re-enable nxinit, with a working console 2026-09-11 21:12:18 +08:00
cmake cmake: Build FDPIC modules the way the make build does. 2026-09-09 10:21:21 +08:00
crypto tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
Documentation tools/refresh.sh: Fix multi-argument parsing 2026-09-10 16:26:53 +02:00
drivers drivers/serial: read the consumer index once in uart_recvchars() 2026-09-10 23:09:16 +08:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs libs/libc/elf: Place an FDPIC object's segments independently. 2026-09-08 16:31:16 -03:00
graphics graphics/nxterm: consume SGR escape sequences 2026-08-23 10:46:02 +08:00
include mm/pgalloc: support 32 KB and 64 KB page sizes 2026-09-10 23:28:43 +08:00
libs arch/arm, libs/libc/elf: Build FDPIC modules in the normal ELF build. 2026-09-09 10:21:21 +08:00
mm mm/pgalloc: support 32 KB and 64 KB page sizes 2026-09-10 23:28:43 +08:00
net net/tcp: add configurable delayed ACK threshold 2026-09-08 09:00:19 +08:00
openamp cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
pass1 tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
sched sched/waitid: honor WNOWAIT instead of discarding child status 2026-09-11 03:00:15 +08:00
syscall fs: rename PSEUDOFS_SOFTLINKS to FS_LINKS 2026-08-27 01:12:33 +08:00
tools tools/nxstyle: whitelist Micro XRCE-DDS type names 2026-09-11 03:00:05 +08:00
video video/videomode: Fix EDID parsing and formatting of video mode dumps 2026-08-29 11:09:11 -03:00
wireless wireless/bluetooth: fix inverted MTU cap in bt_conn_send() 2026-08-30 10:48:18 -03:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines arch/arm: Reserve r10 via ARCHCFLAGS and hoist the PIC module flags. 2026-07-24 23:09:08 +08:00
.codespellrc Revert "zbus: Add linker support and documentation for the zbus port" 2026-08-30 10:45:19 -03:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore boards/risc-v/eic7700x: Adopt the common board layout. 2026-08-19 01:40:57 +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 feat: add a GitHub action to lint the YAML files 2020-12-15 09:52:04 -06:00
AUTHORS AUTHORS: add Jorge Guzman 2026-08-25 08:43:13 -04:00
CMakeLists.txt arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md INVIOLABLES.md: Fix a simple alignment and change occurrences of Nuttx 2020-09-03 01:33:05 +08:00
Kconfig include/nuttx: Add link-time iterable sections infrastructure 2026-08-27 01:04:05 +08:00
LICENSE libs/libdsp: Add Matrix operations 2026-07-11 14:55:59 -03:00
Makefile !boards: enforce secure ROMFS passwd and TEA key setup 2026-07-09 22:41:11 +08:00
NOTICE Remove the double blank line from source files 2022-02-20 20:10:14 +01:00
README.md ci/testing: Add MemBrowse Integration 2026-06-18 12:07:41 -03:00
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.