Work In Progress

NuttX X.Y has not been released yet. These Release Notes are a work-in-progress in preparation for the next release of NuttX. There is a board tracking the PRs that need to be looked at to add to this doc for the OS TODO ADD LINK and for the Apps TODO ADD LINK

What's New In This Release

Major Changes to Core OS

New Features

Bug Fixes

Major Changes to the Build System

New Features

* [#](https://github.com/apache/incubator-nuttx/pull/#)

Architectural Support

New Architecture Support

* [#](https://github.com/apache/incubator-nuttx/pull/#)

Bug Fixes

* [#6070](https://github.com/apache/incubator-nuttx/pull/#6070) MPFS: Set correct interrupt per mode (M-/S-mode) for mtimer

* [#6071](https://github.com/apache/incubator-nuttx/pull/#6071) arm/rtl8720c: Remove up_getsp which is already implemented in arch/arm/arch.h

* [#6072](https://github.com/apache/incubator-nuttx/pull/#6072) arm/armv7-[a|r]: move fpu save/restore to assembly handler

* [#6065](https://github.com/apache/incubator-nuttx/pull/#6065) RISC-V: Support for mtimer in S-mode

* [#6063](https://github.com/apache/incubator-nuttx/pull/#6063) arch/stack_color: correct the stack top of running task

* [#6062](https://github.com/apache/incubator-nuttx/pull/#6062) SAM3X HSMCI DMA Fixes

* [#6060](https://github.com/apache/incubator-nuttx/pull/#6060) MPFS: Fix timer and exception/fault handling

* [#6059](https://github.com/apache/incubator-nuttx/pull/#6059) arch/risc-v/riscv_misaligned: Correct sw source register

* [#6056](https://github.com/apache/incubator-nuttx/pull/#6056) arch/stack_color: correct the end address of stack color

* [#6054](https://github.com/apache/incubator-nuttx/pull/#6054) riscv/riscv_schedulesigaction.c: Remove the duplicate state saving

* [#6051](https://github.com/apache/incubator-nuttx/pull/#6051) arch/risc-v: Add missing DMB to mtimer / setmtimecmp

* [#6050](https://github.com/apache/incubator-nuttx/pull/#6050) RISC-V: Move mhartid to own assembly macro+function

* [#6048](https://github.com/apache/incubator-nuttx/pull/#6048) arm/armv8-m: indicating no low-overhead-loop predication by default

* [#6039](https://github.com/apache/incubator-nuttx/pull/#6039) arch/riscv: Move toolchain config to arch/risc-v/Kconfig like xtensa

* [#6042](https://github.com/apache/incubator-nuttx/pull/#6042) arch/arm: Move FPU initialization to common place

* [#6034](https://github.com/apache/incubator-nuttx/pull/#6034) arch/risc-v: Apply common mtime driver to mtime based chps

* [#6022](https://github.com/apache/incubator-nuttx/pull/#6022) arch/risc-v: Apply misaligned access handler for k210/bl602

* [#6006](https://github.com/apache/incubator-nuttx/pull/#6006) riscv/ESP32C3: Use the common exception handler

* [#6020](https://github.com/apache/incubator-nuttx/pull/#6020) arch/riscv: Add mtimer driver

* [#6008](https://github.com/apache/incubator-nuttx/pull/#6008) arch/risc-v: Attach exception handler in common place

* [#5998](https://github.com/apache/incubator-nuttx/pull/#5998) arch/riscv: Minor style change and text correction

* [#6001](https://github.com/apache/incubator-nuttx/pull/#6001) arm/armv[7|8]-m: skip the fpu save/restore if stack frame is integer-only

* [#6003](https://github.com/apache/incubator-nuttx/pull/#6003) esp32c3: Simplify irq dispatch logic

* [#5993](https://github.com/apache/incubator-nuttx/pull/#5993) MPFS: Prepare support for S-mode

* [#5966](https://github.com/apache/incubator-nuttx/pull/#5966) arch:tcbinfo: update tcbinfo as xcpcontext update

* [#5989](https://github.com/apache/incubator-nuttx/pull/#5989) arch/risc-v: Replace riscv_fault with riscv_exception

* [#5970](https://github.com/apache/incubator-nuttx/pull/#5970) b-u585i-iot02a:nsh: Drop TrustedFirmware-M dependency

* [#5974](https://github.com/apache/incubator-nuttx/pull/#5974) arch/risc-v: use STACK_FRAME_SIZE for in S-mode syscall asm

* [#5979](https://github.com/apache/incubator-nuttx/pull/#5979) arch/xtensa: Build the xtensa_tcbinfo.c file for S2 and S3

* [#5980](https://github.com/apache/incubator-nuttx/pull/#5980) RISC-V: Fix file name of riscv_dispatch_syscall

* [#5987](https://github.com/apache/incubator-nuttx/pull/#5987) xtensa/esp32: Add support to TWAI/CANBus

* [#5985](https://github.com/apache/incubator-nuttx/pull/#5985) RISC-V: Combine 3 variables that depend on CPU amount into one

* [#5981](https://github.com/apache/incubator-nuttx/pull/#5981) RISC-V: Fix usage of static_assert in riscv_percpu.c

* [#5983](https://github.com/apache/incubator-nuttx/pull/#5983) arch/risc-v: Remove the unnecessary inclusion of board header files

* [#5749](https://github.com/apache/incubator-nuttx/pull/#5749) risc-v/mpfs: usb: fix ep0 stall/resume and rx reads

* [#5752](https://github.com/apache/incubator-nuttx/pull/#5752) arch: cxd56xx: Fix critical section in serial transmission

* [#5754](https://github.com/apache/incubator-nuttx/pull/#5754) arch/risc-v: Correct stack coloration in riscv_cpu_boot

* [#5758](https://github.com/apache/incubator-nuttx/pull/#5758) RISC-V: Prepare CONFIG_BUILD_KERNEL part 1

* [#5760](https://github.com/apache/incubator-nuttx/pull/#5760) ESP32-S3: Fix UART IRQ setup hardcoded to CPU 0

* [#5761](https://github.com/apache/incubator-nuttx/pull/#5761) arch/arm: Remove the code copy register from xcpt to stack

* [#5765 ](https://github.com/apache/incubator-nuttx/pull/#5765) esp32 efuse build fix

* [#5766](https://github.com/apache/incubator-nuttx/pull/#5766) arch/risc-v: Rework riscv_get_newintctx

* [#5771](https://github.com/apache/incubator-nuttx/pull/#5771) arch/xtensa: Don't always reset the APP CPU on startup

* [#5772](https://github.com/apache/incubator-nuttx/pull/#5772) arch/Kconfig: Don't depend on Xtensa for the SUPPRESS_CLOCK_CONFIG option

* [#5773](https://github.com/apache/incubator-nuttx/pull/#5773) risc-v/esp32c3: Remove deprecated option for disabling atomics support

* [#5774](https://github.com/apache/incubator-nuttx/pull/#5774) arch/arm: set the SP to stack top

* [#5775](https://github.com/apache/incubator-nuttx/pull/#5775) arch/risc-v: Merge riscv_getnewintctx into common

* [#5780](https://github.com/apache/incubator-nuttx/pull/#5780) MPFS: Add board_memorymap.h

* [#5781](https://github.com/apache/incubator-nuttx/pull/#5781) phy62xx_exception: using armv6-m exception_common code

* [#5782](https://github.com/apache/incubator-nuttx/pull/#5782) RISC-V: Implement option to run NuttX in supervisor mode (S-mode)

* [#5783](https://github.com/apache/incubator-nuttx/pull/#5783) risc-v/mpfs: usb: fix ep0 read done

* [#5809](https://github.com/apache/incubator-nuttx/pull/#5809) fixed mpu9250 not work on i2c bus issue.

* [#5815](https://github.com/apache/incubator-nuttx/pull/#5815) defconfig: add Lua configs for sim and teensy-4.x

* [#5820](https://github.com/apache/incubator-nuttx/pull/#5820) xtensa/esp32(s2)_user.c: Use macros defined in xtens_corebits.h

* [#5824](https://github.com/apache/incubator-nuttx/pull/#5824) arch/arm/src/stm32l4: peripheral voltage monitor support for vddio2

* [#5825](https://github.com/apache/incubator-nuttx/pull/#5825) ESP32-S3: Enable GPIO read/write operations and interrupts support

* [#5827](https://github.com/apache/incubator-nuttx/pull/#5827) Add SPIRAM to ESP32-S2

* [#5829](https://github.com/apache/incubator-nuttx/pull/#5829) RISC-V: Add/fix implementation for arch_elf.c

* [#5830](https://github.com/apache/incubator-nuttx/pull/#5830) risc-v/qemu-rv: Restore FPU context after context switch

* [#5831](https://github.com/apache/incubator-nuttx/pull/#5831) RISC-V: Add kernel stack

* [#5833](https://github.com/apache/incubator-nuttx/pull/#5833) ESP32-S2: Remove unused and unsupported configs from Kconfig

* [#5834](https://github.com/apache/incubator-nuttx/pull/#5834) ESP32-S2: Initialize instruction cache on startup

* [#5876](https://github.com/apache/incubator-nuttx/pull/#5876) xtensa: add xtensa_spill_window declaration

* [#5878](https://github.com/apache/incubator-nuttx/pull/#5878) arch/risc-v: Use riscv_fpuconfig to enable FPU

* [#5881](https://github.com/apache/incubator-nuttx/pull/#5881) MPFS: Fix issue with external interrupt detection

* [#5898](https://github.com/apache/incubator-nuttx/pull/#5898) riscv/bl602: Implement SPI Cmd/Data

* [#5957](https://github.com/apache/incubator-nuttx/pull/#5957) risc-v/esp32c3: Fix regression on IRQ handling for ECALL instruction

* [#5905](https://github.com/apache/incubator-nuttx/pull/#5905) arch/risc-v: Store/Restore FPU register in exception_common

* [#5795](https://github.com/apache/incubator-nuttx/pull/#5795) ESP32-S3: Clean up and improve GPIO driver interface

* [#5838](https://github.com/apache/incubator-nuttx/pull/#5838) esp32/Make.defs: Organise common arch files and chip files appropriately

* [#5865](https://github.com/apache/incubator-nuttx/pull/#5865) arch: Add -fsanitize=kernel-address to ARCHCPUFLAGS if CONFIG_MM_KASAN=y

* [#5864](https://github.com/apache/incubator-nuttx/pull/#5864) arch/Toolchain.defs: add wildcard for EXTRA_LIBS

* [#5863](https://github.com/apache/incubator-nuttx/pull/#5863) arch/arm: Change arm_arch.h to arm_internal.h in arm_perf.c

* [#5868](https://github.com/apache/incubator-nuttx/pull/#5868) arch/risc-v: Move fpu [re]store to common place

* [#5869](https://github.com/apache/incubator-nuttx/pull/#5869) riscv/bl602: Enable SPI Master in SPI Poll Send

* [#5870](https://github.com/apache/incubator-nuttx/pull/#5870) arch/armv7-a: Fix a typo in Toolchain.defs

* [#5875](https://github.com/apache/incubator-nuttx/pull/#5875)MPFS: Fix error in flat build linker script

* [#5877 ](https://github.com/apache/incubator-nuttx/pull/#5877) xtensa: add xtensa arch oneshot ops

* [#5907](https://github.com/apache/incubator-nuttx/pull/#5907)riscv/bl602: Remove check for LCD driver

* [#5908](https://github.com/apache/incubator-nuttx/pull/#5908) riscv/esp32c3: Remove check for LCD driver

* [#5946](https://github.com/apache/incubator-nuttx/pull/#5946) arch/xtensa: Add xtensa_tcbinfo struct that contains helpful offsets

* [#5845](https://github.com/apache/incubator-nuttx/pull/#5845) armv8-m: make the securefault handled by non-securefult

* [#5850](https://github.com/apache/incubator-nuttx/pull/#5850) armv7-m/armv8-m: move up_pref* api to common place

* [#5940](https://github.com/apache/incubator-nuttx/pull/#5940) arch/risc-v: Add handler for misaligned load/store

* [#5941](https://github.com/apache/incubator-nuttx/pull/#5941) arch/xtensa: add syscall note support in the flat build

* [#5917](https://github.com/apache/incubator-nuttx/pull/#5917) arch/risc-v: move REGLOAD/REGSTORE macro to riscv_internal.h

* [#5745](https://github.com/apache/incubator-nuttx/pull/#5745) arch/arm/samv7/sam_tc: implement timer driver support

* [#5746](https://github.com/apache/incubator-nuttx/pull/#5746) RISCV: Fix nasty bug in PMP region test

* [#5842](https://github.com/apache/incubator-nuttx/pull/#5842) arch/risc-v: improve style consistency accross chip variants

* [#5896](https://github.com/apache/incubator-nuttx/pull/#5896) arm/cortex-[a|r]: IRQ Switch return should with shadow SPSR

* [#5897](https://github.com/apache/incubator-nuttx/pull/#5897) ESP32{S2/S3/C3}: Enable support for C++ applications

* [#5912](https://github.com/apache/incubator-nuttx/pull/#5912) arch/risc-v/mpfs: Remove duplicated riscv_restorefpu

* [#5913](https://github.com/apache/incubator-nuttx/pull/#5913)arch/risc-v: Move group_addrenv to correct place

* [#5922](https://github.com/apache/incubator-nuttx/pull/#5922) arch/risc-v: get wider visibility for arch instruction macros

* [#5918](https://github.com/apache/incubator-nuttx/pull/#5918) arm/chip: add backtrace support for all chips that support thumb instruction set

* [#5920](https://github.com/apache/incubator-nuttx/pull/#5920) ARCH_ADDRENV: Add guard against mis-configuration

* [#](https://github.com/apache/incubator-nuttx/pull/#)

* [#5862](https://github.com/apache/incubator-nuttx/pull/#5862) arch/sim: Remove the unused SIM_TCNWAITERS from Kconfig

* [#5923](https://github.com/apache/incubator-nuttx/pull/#5923) sim: Fix initialization of static C++ constructors when using glibc >= 2.34

* [#5885](https://github.com/apache/incubator-nuttx/pull/#5885) sim/rptun: rsc must set rpmsg_vdev.config_len

* [#5756](https://github.com/apache/incubator-nuttx/pull/#5756) sim: Enable garbage collection of unused input sections

* [#5988](https://github.com/apache/incubator-nuttx/pull/#5988) arch/sim: support simulator keyboard devices

* [#6043](https://github.com/apache/incubator-nuttx/pull/#6043) sim: bt: Add specific bluetooth HCI number id

Driver Support

Bug Fixes

* [#6068](https://github.com/apache/incubator-nuttx/pull/#6068) driver/mmcsdio: do not hold the semaphore on interrupt context

* [#6019](https://github.com/apache/incubator-nuttx/pull/#6019) power/governor: Remove the duplicated function prototype

* [#6021](https://github.com/apache/incubator-nuttx/pull/#6021) Test/wm8904balance

* [#6018](https://github.com/apache/incubator-nuttx/pull/#6018) Increase audio_comp driver flexibility

* [#5927](https://github.com/apache/incubator-nuttx/pull/#5927) Minor improve for mmcsd

* [#5747](https://github.com/apache/incubator-nuttx/pull/#5747) drivers/timers: rename notification parameter oneshot to periodic

* [#5849](https://github.com/apache/incubator-nuttx/pull/#5849) pm: remove unnecessary depends on OSINIT_OS_READY

* [#5853](https://github.com/apache/incubator-nuttx/pull/#5853) driver/syslog: Add microseconds after date time

* [#5901](https://github.com/apache/incubator-nuttx/pull/#5901) power: unify lock sates and move pm_auto_update to outer dir

* [#5990](https://github.com/apache/incubator-nuttx/pull/#5990) fix uinput rpmsg logic error

* [#5816](https://github.com/apache/incubator-nuttx/pull/#5816) drivers/mtd/mtd_config: set different format versions for named and ID modes

* [#](https://github.com/apache/incubator-nuttx/pull/#)

New Driver Support

* [#6030](https://github.com/apache/incubator-nuttx/pull/#6030) Add Sensirion's SCD41 driver and minor fix

Drivers With Significant Improvements

Board Support

Significant Improvements

New Board Support

Boards With Significant Improvements

* [#6036](https://github.com/apache/incubator-nuttx/pull/#6036) arch, boards: cxd56xx: Minor update for spresense

* [#6074](https://github.com/apache/incubator-nuttx/pull/#6074) boards/arm/a1x: Remove the check CONFIG_ARCH_FPU around arm_fpuconfig

* [#5964](https://github.com/apache/incubator-nuttx/pull/#5964) boards/nucleo-f446re: support for SystemView

* [#5788](https://github.com/apache/incubator-nuttx/pull/#5788) boards/arm/samv7/same70-qmtech: add gpio driver support

* [#5812](https://github.com/apache/incubator-nuttx/pull/#5812) esp32s3-devkit/spiflash: Use SmartFS instead of LittleFS

* [#5817](https://github.com/apache/incubator-nuttx/pull/#5817) boards/arm/same70-qmtech: Remove dead code

* [#5841](https://github.com/apache/incubator-nuttx/pull/#5841) esp32s3-devkit: Fix the number of memory regions in some configurations

* [#5909](https://github.com/apache/incubator-nuttx/pull/#5909) boards/boardctl:common boardctl to read reset cause

* [#5751](https://github.com/apache/incubator-nuttx/pull/#5751) boards/sim/adb: Enable CONFIG_ADBD_SOCKET_SERVICE

* [#5763](https://github.com/apache/incubator-nuttx/pull/#5763) boards: sabre-6quad: Enable environ and path in knsh/defconfig

* [#5839](https://github.com/apache/incubator-nuttx/pull/#5839) boards: rv-virt: Fix stack corruption for rv64 config

* [#5860](https://github.com/apache/incubator-nuttx/pull/#5860) boards/arm/uid: fix pointer to int compare

* [#5895](https://github.com/apache/incubator-nuttx/pull/#5895) boards: correct path to RCRAWS files during file copy

* [#5785](https://github.com/apache/incubator-nuttx/pull/#5785) boards/arm/samv7: define MTD progmem partitions at board level

* [#5787](https://github.com/apache/incubator-nuttx/pull/#5787) boards/arm/samv7/same70-qmtech: add /dev/timer0 support

* [#5804](https://github.com/apache/incubator-nuttx/pull/#5804) boards/arm/samv7/samv71-xult: Fix mcuboot update example missing config

* [#](https://github.com/apache/incubator-nuttx/pull/#)

File System

Bug Fixes

Significant Improvements

Networking

Applications

Improvements

Bug Fixes

Security Issues Fixed In This Release

Compatibility Concerns

Changes to Build System

Known Problems In This Release

More Information

How to Download

Release artifacts for all current and past NuttX releases can be downloaded at:

https://nuttx.apache.org/download/

How to Clone the Git Repository

The Apache NuttX project uses Git SCM as its version control system.

There are two primary repositories:

nuttx - The real time operating system itself.
apps - Optional applications and example programs for the operating system. You can use this repository or make your own custom one.

The main "Single Source of Truth" repositories are hosted by the ASF:

These are synchronized with repositories hosted at GitHub:

How to Contact the Community

The main forum for project communication, to ask a question, get involved, or contribute to NuttX, is our mailing list, dev@nuttx.apache.org. The list is publicly archived and searchable at https://lists.apache.org/list.html?dev@nuttx.apache.org. For more information, see NuttX Community.

Enthusiastic Contributors Welcome!

NuttX is a free open-source project. If you'd like to participate, whether it's to enhance documentation (even these release notes) or dive into the nitty gritty of some low-level drivers, please join us! You can join the conversation at our dev mailing list by emailing dev-subscribe@nuttx.apache.org. The mailing list is open to the public and archived. You can browse older messages at https://lists.apache.org/list.html?dev@nuttx.apache.org.