Comparison of real-time operating systems


This is a list of real-time operating systems (RTOSs). This is an operating system in which the time taken to process an input stimulus is less than the time lapsed until the next input stimulus of the same type.

Name License Source model Target uses Status Platforms Official website
Abassi Proprietary closed embedded active AVR32, ATmega, ColdFire, Cortex-A53, Cortex-A9, -M0, -M3, -M4, MSP430, PIC32, TMS320C2000, 80251, 8051
Amos Proprietary ? commercial closed 680x0, 683xx, x86 via emulation
AdAstra-RTK BSD 3-clause open source embedded active Cortex-M3-M4-M7-H7, STM32
AMX -RTOS Proprietary closed 680x0, 683xx, ARM, ColdFire, MIPS32, PowerPC, x86
Apache Mynewt Apache 2.0 open source ARM Cortex-M, MIPS32, Microchip PIC32, RISC-V
Arm OS Apache 2.0 Cortex-M, Cortex-R, Cortex-A
uKOS GNU GPL Cortex-M3-M4-M7-H7, 6833x, PIC, CSEM icyflex-1, STM32
ARTOS (Locamation) Proprietary closed power-system automation x86
ARTCOS (Robotu) Proprietary ? embedded, robots defunct ARM9+
Atomosher BSD open source embedded active AVR, STM8, ARM, MIPS
AVIX Proprietary closed Atmel AT91SAM3(U/S), EFM32, NXP LPC1300-1700, ST Micro STM32, Texas Instruments LM3S, Toshiba TMPM330, Microchip PIC32MX-PIC24F-PIC24H-dsPIC30F-dsPIC33F
BeRTOS modified GNU GPL open source archived ARM, Cortex-M3, ARM ARM7TDMI, Atmel AVR, PowerPC (emu), x86 (emu), x86-64 (emu)
BOOS-Mooch Core GNU GPL active ARMv5TEJ (TI AM18x), DSP (TI TMS320C64x)
BRKos MIT Freescale Kinetis (ARM Cortex-M4), NXP ColdFire V1, Freescale HCS08, ST STM32F4xx (ARM Cortex-M4F), NXP LPC11xx (ARM Cortex-M0), NXP LPC176x (ARM Cortex-M3), Renesas RX600 (RX62N), Texas Instruments MSP430, Texas Instruments Stellaris LM3S8968 (ARM Cortex-M3), Texas Instruments Stellaris LM4F120H5QR (ARM Cortex-M4F), Atmel ATMEGA328/128 and Microchip PIC18
Cesium RTOS Proprietary source available to licensees active ARM7-9-11/Cortex-M1-3-4-7-A8/9, AVR, HC11/12/S12, ColdFire, Blackfin, MicroBlaze, NIOS, 8051, x86, Win32, H8S, M16C, M32C, MIPS, 68000, PIC24/dsPIC33/PIC32, MSP430, PowerPC, SH, StarCore, Renesas RX100-200-600-700, RL; STM32
ChibiOS/RT Mixed, GNU GPL or proprietary open source embedded, small footprint x86, ARM7, ARM9, Cortex-M0-M3-M4, PowerPC e200z, STM8, STM32, AVR, MSP430, ColdFire, H8S,
ChorusOS ? ? ? defunct SPARC, x86, PowerPC
ChronOS GNU GPL open source research, general purpose active x86, ARM
CoActionOS (now Stratify OS) Modified GNU GPL or proprietary embedded discontinued ARM Cortex-M3, LPC17xx
cocoOS BSD active AVR, MSP430, STM32
Concurrent CP/M,
became MP/M
Proprietary closed (meanwhile: open source) general purpose, industrial historic 8080, Z80, 8086 Digital Research
Concurrent DOS,
became Multiuser DOS
Proprietary closed defunct 8086, 286, 386, 68000, (also 8080/Z80 in dual-processor variants) Digital Research
Contiki BSD open source embedded, WSN active MSP430, AVR, ARM
COS Proprietary closed process control defunct GEC 4000 series ?
CooCox CoOS BSD open source general purpose inactive STM32, NXP LPC1000, TI LM3S8962, Nuvoton NU1xx, Holtek HT32
Deos Proprietary closed safety critical active x86, PowerPC, MIPS
DioneOS Proprietary available for licensee embedded MSP430, MSP430x
distortos Mozilla open source embedded active ARMv6-M architecture (ARM Cortex-M0, ARM Cortex-M0+, ARM Cortex-M1): STM32F0, STM32L0; ARMv7-M architecture (ARM Cortex-M3, ARM Cortex-M4(F), ARM Cortex-M7(F)): STM32F1, STM32F4, STM32F7, STM32L4
DNIX Proprietary closed general purpose defunct 68000 ?
dnx RTOS GNU GPL, modified GPL, BSD open source embedded (Unix-like) active ARM Cortex-M3, STM32
GEC DOS Proprietary closed process control defunct GEC 4000 series ?
Drone OS Apache 2.0/MIT open source embedded active ARMv7-M, ARMv8-M, RISC-V
DSOS ? ? ? defunct TI-980A minicomputer ?
DSP/BIOS Free closed, available with license general purpose maintenance only Mostly Texas Instruments C2800, C5500, C6000 and OMAP DSP cores. Replaced by TI-RTOS, but available for download.
DSPnano RTOS Mixed, open source and commercial open source MCU, DSC, DSP SoC active R8C, M16C, PIC24, dsPIC33
DuinOS Modified GNU GPL open source general purpose AVR (Arduino)
eChronos CSIRO BSD MIT open source embedded ARM Cortex-M3 - M7
eCos Modified GNU GPL open source ARM-XScale-Cortex-M, CalmRISC, 680x0-ColdFire, fr30, FR-V, H8, IA-32, MIPS, MN10300, OpenRISC, PowerPC, SPARC, SuperH, V8xx
eCosPro Modified GNU GPL or eCosPro license open source with non-free portions ARM7-9, Cortex-A5-A9-M3-M4-M7, 680x0-ColdFire, H8-H8S, IA-32, MIPS32, MIPS64, microMIPS, NIOS II, OpenRISC, PowerPC, SPARC, SH4/4A, TILE-Gx, XScale
embOS Proprietary closed, available to customers, free object code for non-commercial use embedded, industrial, IoT, safety critical active ARM7/9/11, ARM Cortex-A/R/M, AVR, AVR32, C16x, CR16C, ColdFire, H8, HCS12, M16C, M32C, MSP430, NIOS2, PIC18/24/32, R32C, R8C, RISC-V, RL78, RH850, RX100/200/600/700, RZ, SH2A, STM8, ST7, V850, 78K0, 8051
Embox BSD open source embedded ARM, LEON, MicroBlaze, MIPS, PowerPC, x86
Embkernel GNU LGPL ARM Cortex M
ERIKA Enterprise GPL and GPL linking exception ARM7, ARM Cortex-M, ARM Cortex-A (on Jailhouse hypervisor), Hitachi H8, Altera Nios2, Microchip dsPIC (including dsPIC30, dsPIC33, and PIC24), Microchip PIC32, ST Microelectronics ST10, Infineon C167, Infineon Tricore, Freescale PPC e200 (MPC 56xx) (including PPC e200 z0, z6, z7), Freescale S12XS, EnSilica eSi-RISC, AVR, Lattice Mico32, MSP430, Renesas RX200, x86-64 (on Jailhouse hypervisor)
EUROS Proprietary closed 8/16/32 bit processors: among others AVR, 8051, XC800, 16FX, XC166, ARM, Cortex-M3, PowerPC, Nios II, MIPS32, PIC32
EROS Modified GNU GPL open source experimental
research use
dormant IA-32
F9 microkernel Modified BSD embedded maintenance ARM Cortex-M3/M4
Femto OS GNU GPLv3 embedded active AVR
Flexible Safety RTOS Proprietary closed, available to customers embedded, safety critical active ARM9, ARM Cortex-M, ARM Cortex-R, ARM Cortex-A, ColdFire, QorIQ, Infineon TriCore, Infineon AURIX
FlexOS Proprietary closed general purpose, industrial, POS defunct 186, 286, 386, V60, V70, 68000 Digital Research, Novell
FreeOSEK GNU GPLv3 open source embedded active Cortex-M4, MIPS, MSP430, SPARC LEON3
FreeRTOS MIT ARM, AVR, AVR32, ColdFire, ESP32, HCS12, IA-32, Cortex-M3-M4-M7, Infineon XMC4000, MicroBlaze, MSP430, PIC, PIC32, Renesas H8/S, RISC-V, RX100-200-600-700, 8052, STM32, TriCore, EFM32
Frosted GNU GPL embedded, POSIX compliant, unix-like ARM Cortex-M
Fuchsia Varies embedded AArch64, x86-64
FunkOS modified Sleepycat License embedded AVR, MSP430, Cortex-M3
Fusion RTOS Free ? semi-general purpose ARM, Blackfin, StarCore, DSP 56800E
FX-RTOS Proprietary source code provided embedded ARMv6-M (Cortex-M0/M1), ARMv7-M (Cortex-M3), ARMv7-A (including Cortex A9 MPCore), x86, AVR32, PIC32, MIPS M4K, TI MSP430,
HeartOS Proprietary closed safety critical x86, PowerPC, ARM
Helium GNU LGPL open source Embedded HCS08, AVR
HP-1000/RTE ? ? ? ? ?
Hybridthreads ? open source FPGA active Xilinx Virtex-II Pro ML310, Xilinx Virtex-II Pro XUP
hyperCOS ? free evaluation (not open source) embedded ARM7, ARM9, Cortex-R, Cortex-M3, Cortex-M4F
IBM 4680 OS Proprietary closed general purpose, industrial, POS defunct 286 IBM (DR Concurrent DOS 286 derivative)
IBM 4690 OS Proprietary active 286, 386 IBM (DR FlexOS 286/386 derivative)
INTEGRITY Proprietary embedded ARM, XScale, Blackfin, ColdFire, MIPS, PowerPC, x86
INtime Proprietary x86
IntrOS MIT open source embedded, small footprint ARM Cortex-M, STM8, AVR8
ITRON T-License varies embedded ARM, MIPS, x86, Renesas RX100-200-600-700-others
ISIX GNU LGPL open source Cortex-M3
KolibriOS GNU GPL embeddable active x86
Kithara RTS Proprietary closed general purpose, industrial Windows extension, x86, x86-64, Windows XP-10
Lepton Mozilla open source embeddable ARM9 (ATMEL AT91SAM9261, AT91SAM9260), ARM7 (ATMEL AT91SAM7x, AT91SAM7SE, AT91M55800), CortexM3 (ST STM32F103, Texas Instrument Stellaris) et CortexM4 (Freescale Kinetis)
LithOS Proprietary ? embedded, industrial LEON2-3-4, x86,
LxWin Proprietary closed MS Windows extension x86
LynxOS Proprietary source code available embedded Motorola 68010, x86/IA-32, ARM, Freescale PowerPC, PowerPC 970, LEON
Maestro Proprietary closed ARMv7-A, ARMv8-A, PowerPC64, IA-32
Mark3 BSD open source active, beta ?
MaRTE OS GNU GPL active IA-32
MAX II, IV Proprietary ? ? ? MODCOMP II, IV, ... ?
MenuetOS GNU GPL open source ? active IA-32
Menuet 64 Proprietary unknown ? IA-32, x86-64 ?
MicroC/OS-III Apache 2.0 open source embedded ARM7-9-11/Cortex-M1-3-4-A8/9, AVR, HC11/12/S12, ColdFire, Blackfin, MicroBlaze, NIOS, 8051, x86, Win32, H8S, M16C, M32C, MIPS, 68000, PIC24/dsPIC33/PIC32, MSP430, PowerPC, SH, StarCore, Renesas RX100-200-600-700, RL; STM32, …
Milos GNU GPL Cortex-M3
miosix GNU GPL stm32, efm32 e LPC2000
mipOS Proprietary Cortex-M3, ST7, STM8, x86
Microsoft Invisible Computing (MMLite) Proprietary ARM7-9, i386, h8, mips, Trimedia, eCog1
mLithOS Proprietary ? embedded, industrial LEON2-3-4, x86,
MOTORCORTEX Proprietary server: closed, clients: open source x86, ARM,
MP/M Proprietary closed (meanwhile: open source) general purpose, industrial defunct 8080, Z80, 8086 Digital Research
MQX Proprietary complimentary source code available embedded active Freescale Power, ColdFire, Kinetis Cortex ARM, List of Freescale products
MERT ? ? ? inactive PDP-11 ?
Multiuser DOS Proprietary closed general-purpose, industrial defunct 386 Digital Research/Novell, Concurrent Controls, Datapac, IMS (see REAL/32)
Nano-RK Mixed open source embedded, WSN active AVR, MSP430
Neutrino Proprietary some source code provided microkernel ARM, MIPS, PPC, SH, x86, XScale
NI Linux Real-Time Proprietary developed from open source data acquisition and process control National Instruments CompactRIO controllers
nOS Mozilla open source embedded AVR, MSP430, Cortex-M0-M3-M4, M16C, RX600, PIC24, Win32, POSIX, STM8
Nucleus RTOS Proprietary source code provided ARM (Cortex-M3-M4-R4-R4F-A8-A9, ARM7-9-11), PowerPC, MIPS32-16e, microMIPS, ColdFire, SuperH
NUFR Modified BSD open source ARM (Cortex-M0,-M3,-M4), MSP430, MSP430X (16- and 20-bit models)
Nut/OS BSD open source embedded, industrial AVR, AVR32, ARM7, ARM9, Cortex-M3
NuttX Apache 2.0 open source embedded, small footprint Linux user mode, ARM7-9, Cortex-A5-A8-A9-M0-M3-M4-M7, 8052, Espressif ESP32, Lattice LM32, Renesas MC16C/26/SH-1, RISC-V, Zilog Z16F, Zilog eZ80 Acclaim!, Zilog Z8Encore!, Z80, MIPS PIC32MX, PIC32MZ
OpenEPOS Proprietary open source embedded ARM, x86, AVR, MIPS, PowerPC
OS20 Proprietary closed embedded (STB) maintenance only ST20 ?
OS2000 Proprietary ? embedded active MIPS (Baget-MIPS variant), KOMDIV-32, KOMDIV-64, Intel BSPs (x86)
OS21 Proprietary source code provided embedded (STB) active ST40/SH4, ST200, ARM ?
OS4000 Proprietary closed process control maintenance only GEC 4000 series ?
OpenRTOS Proprietary source code available embedded active Same as FreeRTOS
OSA BSD open source PIC10-PIC24, AVR 8-bit, STM8
OSE Proprietary available to customers general purpose ARM, PowerPC, x86, TI OMAP, …
OS-9 Proprietary available to customers embedded ARM-strongARM, MIPS, PowerPC, SuperH, x86/Pentium, XSCALE, Motorola 6809, 680x0, SPARC
OSEK Mixed, open source and commercial specification engine control units Various (mostly Automotive) vendors implemented and distribute/sell OSEK
Partikle Proprietary ? embedded, industrial LEON2-3-4, x86,
Phar Lap ETS ? ? ? ? ? ?
PaulOS GNU GPL open source embedded ? ?
PICOS18 GNU GPL open source ? PIC18 ?
picoOS Modified BSD open source maintenance 6502, 80x86, ARM7, AVR, PowerPC, Cortex-M, MSP430, PIC32,
Piko/RT Modified BSD open source active ARM Cortex-M3/M4
Pharos Apache 2.0 open source embedded, industrial, safety critical ARM (ARM926, Cortex-R5, Cortex-M4, Cortex-A53 - 64 bits), RISC-V (64 bits) (all with memory protection)
Phoenix-RTOS BSD open source embedded ARMv7 Cortex-M, ARMv7 Cortex-A, IA-32, RISC V
PikeOS Proprietary available to customers certifiable safety & security, embedded virtualisation PPC, x86, ARM, MIPS, SPARC-LEON,
Portos Proprietary source code provided embedded, small footprint (ARM soon)
POK BSD open source embedded x86, PowerPC, SPARC
PowerTV Proprietary ? ? ? ?
Prex BSD open source microkernel active ARM, IA-32
Protothreads BSD open source general purpose Architecture independent
pSOS Proprietary ? ? discontinued 680x0 ?
QNX Proprietary ? general purpose, medical devices active IA-32, MIPS, PowerPC, SH-4, ARM, StrongARM, XScale
QP Dual, open source and commercial dual MCU, DSC, DSP SoC ARM7/9, ARM Cortex-M3-M0, MSP430, TMS320C28x, AVR, AVRXmega, ColdFire, 68HC08, M16C/R8C, H8, 8051, 80251, PIC18, PIC24/dsPIC33, Nios II, PSoC1
Quest Apache 2.0 open source embedded / mixed-criticality x86
Kaspersky OS Proprietary ? safety critical, virtualization ? ?
Data General RDOS Proprietary ? general purpose defunct Data General Nova, Data General Eclipse ?
ReaGOS Proprietary closed, available with license embedded active x86, ATmega, ARM, portable
REAL/32 Proprietary closed general-purpose, industrial 386 IMS (Multiuser DOS derivative)
RedHawk Linux (RHEL, CentOS; Ubuntu compatible) Proprietary closed, available with license Hard Real-Time: server, workstation; embedded x86, ARM
Real-time Linux (CONFIG_RT_PREEMPT) GNU GPLv2 open source general purpose same as Linux,,
REX OS Proprietary closed, available with license embedded inactive ARM ja:REX OS
RIOT GNU LGPL open source active ARM, MSP430, AVR, x86, RISC-V
RMX Proprietary closed defunct 8080, 8086, 80386 or higher
RODOS BSD source code provided active ARMv7 (M3, A8, A9), AVR32, PowerPC 405, sparc64

Platforms: SmartFusion2, RaspberryPi, STM32 On top of OS: Linux, Windows, MacOS, FreeRTOS, RTems

rodos download
RSX-11 Proprietary ? ? historic PDP-11 n/a
RT-11 Proprietary ? general purpose defunct PDP-11 n/a
RTAI GNU GPL open source general purpose active x86 (with and without FPU and TSC), x86-64, PowerPC, ARM (StrongARM; ARM7: clps711x-family, Cirrus Logic EP7xxx, CS89712, PXA25x), m68k (supporting both MMU and NOMMU cpus)
RTEMS modified GNU GPL embedded ARM, Blackfin, ColdFire, TI C3x/C4x, H8/300, x86, 68k, Milkymist SoC, MIPS, Nios II, PowerPC, SuperH, SPARC, ERC32, LEON, Mongoose-V
RTLinux GNU GPL general purpose inactive same as Linux Official vendor Wind River Linux
RTOS-UH[1] Proprietary ? embedded ? 68k, 683xx, PowerPC, MPC5xx
RTOS-32 Proprietary, royalty free source available embedded active x86
RT-Thread Apache 2.0 open source embedded ARM, ARM Cortex-M0-M3-R4-M4-M7, IA-32, AVR32, Blackfin, nios, PPC, M16C, MIPS (loongson-1b-1c, PIC32,xburst), MicroBlaze, V850, unicore32,,
RTXC Quadros Proprietary source available embedded ARM - Atmel/Freescale/NXP/ST/TI, Blackfin, 680x0-ColdFire, PowerPC, StarCore, TI-Luminary Stellaris, TI OMAP, XScale
RTX, RTX64 Proprietary closed MS Windows extension x86, x86-64 RTX64 RTOS, Real-Time Solutions for Windows 10 IoT (
RTX Keil Apache 2.0 open source embedded ARM
Ruff Proprietary closed embedded, general purpose, industrial, IoT ARM, MIPS, x86
RX116 ? ? embedded, industrial defunct NEC V20, NEC V30, NEC V40, NEC V50 first ITRON 1 compatible 16-bit RTOS
RX616 ? ? safety critical, embedded, industrial NEC V60, NEC V70 32-bit ITRON compatible
RX-UX832 ? ? embedded, industrial, general-purpose NEC V60, NEC V70 32-bit Unix-like RTOS
SafeRTOS Proprietary source code & Design Assurance Pack available embedded, safety critical active Same as FreeRTOS Same as FreeRTOS
SCIOPTA Proprietary closed, source available embedded, safety related ARM, Cortex-M0-M3-M4, Cortex-R4, -A5, -A7, -A9, -A53, XScale, Renesas RX100, RX200, RX600, RX700, PowerPC, ColdFire, HCS12, M16C, Windows (simulation), Aurix TC2xx, BlackFin BF52x, BF70x
scmRTOS Free open source embedded ARM, Cortex-M3, Blackfin, MSP430, AVR, STM8
SDPOS GNU LGPL embedded ARM, Cortex-M3, Blackfin, PIC18, PIC24, i386 win32/linux synthetic targets
SHaRK GNU GPL ? inactive ?
silRTOS Free embedded active ARM, Cortex-M3 -A9 -11MP, Blackfin, MIPS, AVR
Simba MIT active, beta Arduino Nano (AVR), Arduino Mega (AVR), Arduino Due (ARM), ESP8266, ESP32, cygwin/linux
SimpleAVROS GNU GPLv3 AVR ATmega48 n/a
SINTRAN III ? ? ? ? Norsk Data computers n/a
SOOS Project Free open source embedded active, beta H8/300
StateOS MIT embedded, small footprint active ARM Cortex-M, STM8
Stratify OS Modified GNU GPL or proprietary embedded ARM Cortex-M3, M4
Symbian OS Eclipse defunct ARM
Talon DSP RTOS Proprietary ? embedded DSP active TMS320
TargetOS Proprietary available to customers embedded ARM, Cortus, NXP ColdFire, PowerPC
T-Kernel T-License source available embedded RTOS ARM, MIPS, SH, more
THEOS ? ? ? ? ?
ThreadX Proprietary partial source available ? active ARC, ARM/Thumb, AVR32, BlackFin, 680x0-ColdFire, H8-300H, Luminary Micro Stellaris, M-CORE, MicroBlaze, PIC24-dsPIC, PIC32, MIPS, V8xx, Nios II, PowerPC, Renesas RX100, RX200, RX600, RX700, Synergy, SH, SHARC, StarCore, STM32, StrongARM, TMS320C54x, TMS320C6x, x86/x386, XScale, Xtensa/Diamond, ZSP
TizenRT Apache 2.0 open source embedded ARM
TI-RTOS Kernel (SYS/BIOS) BSD open source Mostly Texas Instruments: MSP430-432, C2000-5000-6000, TI's ARM families (Cortex M3-4F-R4-A8-A15), SimpleLink Wireless CC2xxx-CC3xxx
Tock OS Apache 2.0/MIT open source ARM Cortex, RISC-V
Trampoline Operating System (OSEK and AUTOSAR) GNU GPLv2 open source embedded active Arduino Uno (AVR - ATMega), Arduino Mega (AVR - ATMega), XPlainedPro (Cortex-M0+), Raspberry Pi 2 Model B (Cortex-A7), Olimex LPC-L2294-1MB (ARM7 - NXP LPC2294), Teensy31 (Cortex-M4), XPC56XX EVB + XPC56XL MINI-MODULE (PowerPC - MPC564xL), ZedBoard (RISC-V - PULPino), STM32F4DISCOVERY (Cortex-M4 - STM32F40x), Nucleo-32 (Cortex-M4 - STM32F30x), Cortex-M3 - SmartFusion2, virt-V7 (builds a firmware with TrampolineRTOS that can be used as a guest on the hypervisor XVisor)
TNKernel BSD open source ARM, PIC24-32-dsPIC, HCS08, STM32 (Cortex-M3)
TNeo BSD Cortex-M0-M0+-M1-M3-M4-M4F, PIC24-32-dsPIC
Transaction Processing Facility Proprietary mixed general purpose IBM Z series
TRON project Free mixed mixed active any: is a specification, not an implementation
TUD:OS GNU GPL open source ? ARM, IA-32, x86-64
Ultibo Core GNU GPL open source Embedded unikernel Raspberry Pi including the A, B, A+ and B+ as well as the Raspberry Pi 2B, 3B, 4B/400/CM4 and Zero.
Unison RTOS Mixed, open source and commercial open source MCU, DSC, DSP SoC, FPGA Pic32, ARM Cortex (TI Stellaris Tiva Sitara, ST STM32, NXP LPC1X00, Freescale iMX6 Kinetis, Renesas RZ, RX600, SH2A, SH2AFPU, R32C, MIPS4K, {SHARC, ColdFire, Xilinx MicroBlaze, proprietary}
UNIX-RTR ? ? ? defunct PDP-11 ?
uSmartx BSD open source embedded ? ARM7TDMI, AVR, H8
µITRON T-License open source embedded active ARM, MIPS, x86, Renesas RX100-200-600-700-others
u-velOSity Proprietary ? microkernel active ?
velOSity ? ? ? Power ISA, ARM/XScale, MIPS, x86/Pentium, ColdFire, Blackfin, OMAP, DaVinci
VAXELN Proprietary closed source ? historic VAX
VRTX Proprietary ? ? superseded by Nucleus RTOS ARM, MIPS, PowerPC, RISC
VxWorks Proprietary ? embedded active ARM, IA-32, Intel 64, MIPS, PowerPC, SH-4, StrongARM, xScale
Windows CE Proprietary Microsoft Shared Source x86, MIPS, ARM, SuperH
Windows 10 IoT Proprietary ? Intel Atom, Celeron and Pentium, Qualcomm Snapdragon, Broadcom, NXP i.MX
Xenomai GNU GPLv2 open source general x86, x86-64, PowerPC, ARM, Analog Devices Blackfin BF52x, BF53x, BF54x and BF56x
XINU Free embedded active x86, MIPS, ARM, AVR
XMK BSD embedded inactive-beta ?
Simulink Real-Time Proprietary closed real-time testing-embedded active x86
Y@SOS GNU LGPL open source embedded Cortex-M3, STM32
MontaVista Linux GNU GPL ?
UNOS ? ? ? historic 680x0 ?
uOS GNU GPL open source embedded active AVR, ARM, MIPS32, MSP430, Intel i386, Linux386
Huawei LiteOS BSD ARM (M0/3/4/7, A7/17/53, ARM9/11), x86, RISC-V
Zephyr Apache 2.0 ARM (Cortex-M0, -M3, -M4, -M23, -M33, -R4, -R5, -A53), x86, x86-64, ARC, RISC-V, Nios II, Xtensa, SPARC


  1. ^ "Climbing and Walking Robots and the Support Technologies for Mobile Machines" 2002. p. 157. quote: "Real-Time Operating System - Universität Hannover"
  2. ^ "Windows Processor Requirements".
  3. ^ "Windows for Internet of Things (IoT) Platforms & Applications". Microsoft Windows for Business.

External links

  • Comparison of real-time operating systems at Curlie