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Marco Casaroli 52e3c8fb64 boards/mps2-an521: Correct the swapped UART0 TX and RX interrupts.
The SSE-200 subsystem the AN521 image implements lists the UART interrupts
receive first: UART0 RX is external interrupt 32 and UART0 TX is 33, which
in NuttX numbering are 48 and 49.  The configuration had those two the wrong
way round, so the TX interrupt was dispatched to uart_cmsdk_rx_interrupt.

That handler clears only UART_INTSTATUS_RX, so the asserted TX status bit
survived the acknowledgement and the interrupt re-fired immediately.  The
board live-locked in the interrupt handler as soon as the console emitted its
first character: the NSH banner appeared, and nothing ran afterwards, console
input included.

Note that the overflow interrupt already sits at 63, external 47, which is
where the SSE-200 map puts it only if the pair below it is receive first --
the two corrected values are the ones consistent with it.  mps2-an500 already
follows the same order with RX at 16 and TX at 17.

Assisted-by: Claude Code:claude-opus-5
Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>
2026-08-03 23:17:11 +08:00
.github !arch/stm32: move stm32l1 and finalize the directory split 2026-07-03 10:27:27 +08:00
arch arch/rp23xx: Fix six register/bit macro name clashes. 2026-08-03 23:17:05 +08:00
audio drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-08-03 17:23:22 +08:00
binfmt fs/binfmt: Enforce POSIX execute permissions prior to binary load 2026-06-17 17:11:07 +08:00
boards boards/mps2-an521: Correct the swapped UART0 TX and RX interrupts. 2026-08-03 23:17:11 +08:00
cmake cmake: Sanitize NAME for _main symbol generation 2026-08-03 20:59:22 +08:00
crypto drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-08-03 17:23:22 +08:00
Documentation docs/raspberrypi-4b: Documentation about the SD card updated 2026-08-03 20:57:47 +08:00
drivers drivers/video: zero message on MIPI DSI driver 2026-08-03 23:16:13 +08:00
dummy
fs drivers/eeprom: I2C EEPROM Read/Write Kernel Operations Cause a Device Crash 2026-08-03 21:00:39 +08:00
graphics drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-08-03 17:23:22 +08:00
include lib/math32: Avoid __uint128_t casts for LDC ImportC 2026-08-03 22:20:43 +08:00
libs libc/time: Fix POSIX timezone string parsing. 2026-08-03 22:21:19 +08:00
mm mm/gran: reject pools with too many granules 2026-07-03 10:32:15 +08:00
net fix(net/igmp): restore General Query handling broken by pointer compare 2026-08-03 17:22:28 +08:00
openamp openamp: fix CMake dcache option 2026-05-10 15:03:24 +02:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched sched/addrenv: do not dereference a NULL address environment 2026-08-03 23:15:29 +08:00
syscall syscall: fcntl param3 type to uintptr_t 2026-04-27 12:01:55 -03:00
tools tools/Zig.defs: Fix Zig builds on sim:x86_64 2026-08-03 21:02:20 +08:00
video video: fix EDID standard timing decode 2026-08-03 20:59:41 +08:00
wireless drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-08-03 17:23:22 +08:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines !boards: Remove NSH_ARCHINIT and board_app_initialize 2026-05-02 18:36:46 +08:00
.codespellrc arch/sim: replace macOS C++ constructor runtime hack with post-link patch 2026-05-19 07:08:55 -03:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore git: Specify multiple build directories in .gitignore. 2026-05-20 03:06:58 +08:00
.gitmessage docs/contributing: Add a commit message template 2025-06-03 17:33:24 +08:00
.pre-commit-config.yaml
.yamllint
AUTHORS AUTHORS: add Eren Terzioglu 2026-05-20 15:17:00 +08:00
CMakeLists.txt cmake: Do not link an executable to detect the compiler. 2026-08-03 22:21:10 +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 sched/misc/assert: Add CONFIG_SCHED_DUMP_TASKS and CONFIG_SCHED_DUMP_STACK 2026-07-04 13:29:32 -04:00
LICENSE !arch/stm32: move stm32l1 and finalize the directory split 2026-07-03 10:27:27 +08:00
Makefile !boards: enforce secure ROMFS passwd and TEA key setup 2026-07-06 12:04:07 -03:00
NOTICE
README.md docs: Fix typos, formatting, and numbering in README.md and CONTRIBUTING.md. 2026-03-23 12:05:24 +01:00
ReleaseNotes

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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.