Supported Hardware

Updated: Jan 2026

CMRX real-time operating system is designed to run on microcontrollers. Microcontrollers are low-power devices having limited amount of resources such as RAM and Flash memory. Microcontrollers also usually don’t contain memory management unit and it is not possible to run Linux or similar operating system there.

Supported CPU families

CMRX supports following microcontroller families:

• ARM Cortex-M0+
• ARM Cortex-M3
• ARM Cortex-M4 (both with and without FPU extension)
• ARM Cortex-M7
• ARM Cortex-M23
• ARM Cortex-M33

All ARM cores of ARMv6-M and ARMv7-M are supported as long as they are equipped with ARM Cortex MPU peripheral.

Supported MCU families

This is a brief list of microcontrollers with known level of support. This list is by no means complete and the fact that device is not present in this list does not mean that the microcontroller is not supported.

Manufacturer	Model Family	CPU Core	SDK / HAL	Supported	Notes
Linus Torvalds	Linux	any	any	Yes	*6
Microchip	PIC32CK	Cortex-M33	MPLAB X	Yes
Microchip	PIC32CM GV00	Cortex-M0+	MPLAB X	Yes
Microchip	PIC32CM JHxx	Cortex-M0+	MPLAB X	Yes
Microchip	PIC32CM LX	Cortex-M23	MPLAB X	Yes
Microchip	PIC32CM MC	Cortex-M0+	MPLAB X	Yes
Microchip	PIC32CX	Cortex-M4	MPLAB X	Yes
Microchip	PIC32CZ	Cortex-M7	MPLAB X	Yes
Microchip	SAM 4	Cortex-M4	MPLAB X	Yes
Microchip	SAM C	Cortex-M0+	MPLAB X	Yes
Microchip	SAM D	Cortex-M0+	MPLAB X	Yes
Microchip	SAM D5x	Cortex-M4	MPLAB X	Yes
Microchip	SAM E5x	Cortex-M4	MPLAB X	Yes
Microchip	SAM E7x	Cortex-M7	MPLAB X	Yes
Microchip	SAM G	Cortex-M4	MPLAB X	Yes
Microchip	SAM L21/L22	Cortex-M0+	MPLAB X	Yes
Microchip	SAM L10/L11	Cortex-M23	MPLAB X	Yes
Microchip	SAM S7x	Cortex-M7	MPLAB X	Yes
Microchip	SAM V7x	Cortex-M7	MPLAB X	Yes
Nordic Semiconductor	nRF51	Cortex-M0	nRF5 SDK	No
Nordic Semiconductor	nRF52	Cortex-M4	nRF5 SDK	Yes
Nordic Semiconductor	nRF53	Cortex-M33	nRF-Connect SDK	No	*4
Nordic Semiconductor	nRF54	Cortex-M33	nRF-Connect SDK	Yes	*5
Nordic Semiconductor	nRF91	Cortex-M33	nRF-Connect SDK	No	*4
NXP	Kinetis	Cortex-M	any	No	*3
ST Microelectronics	STM32C0	Cortex-M0+	CubeMX	Yes
ST Microelectronics	STM32F0	Cortex-M0	CubeMX	No
ST Microelectronics	STM32F1	Cortex-M3	CubeMX	Yes
ST Microelectronics	STM32F2	Cortex-M3	CubeMX	Yes
ST Microelectronics	STM32F3	Cortex-M4	CubeMX	Yes
ST Microelectronics	STM32F4	Cortex-M4	CubeMX	Yes
ST Microelectronics	STM32F7	Cortex-M7	CubeMX	Yes
ST Microelectronics	STM32G0	Cortex-M0+	CubeMX	Yes
ST Microelectronics	STM32G4	Cortex-M4	CubeMX	Yes
ST Microelectronics	STM32H5	Cortex-M33	CubeMX	Yes
ST Microelectronics	STM32H7	Cortex-M7	CubeMX	Yes
ST Microelectronics	STM32L0	Cortex-M0+	CubeMX	Yes
ST Microelectronics	STM32L4	Cortex-M4	CubeMX	Yes
ST Microelectronics	STM32L4+	Cortex-M4	CubeMX	Yes
ST Microelectronics	STM32L5	Cortex-M33	CubeMX	Yes
ST Microelectronics	STM32N6	Cortex-M55	CubeMX	Not yet	*1
ST Microelectronics	STM32U0	Cortex-M0+	CubeMX	Yes
ST Microelectronics	STM32U3	Cortex-M33	CubeMX	Yes
ST Microelectronics	STM32U5	Cortex-M33	CubeMX	Yes
Raspberry Pi	RP2040	Cortex-M0+	Pico-SDK	Almost	*2
Raspberry Pi	RP235x	Cortex-M33	Pico-SDK	Yes	ARM mode only

1. Basic ARMv8-M architecture support is present. All Cortex-M23, Cortex-M33 and potentially Cortex-M55 MCUs are now supported. Entries marked previously as Not Yet in table above were changed to Yes.
2. While the CPU itself is supported the way how Pico-SDK is organized and calls routines in BootROM makes the use of CMRX on this CPU complicated.
3. Microcontrollers made by NXP are equipped with NXP-specific MPU which is not compatible with ARM Cortex-M MPU.
4. nRF Connect SDK is essentially a distribution of Zephyr RTOS with Nordic Semiconductor drivers bundled. To our best knowledge this SDK does not contain necessary CMSIS headers and thus is not directly usable with CMRX.
5. See also note 4 above. In August 2025 Nordic Semiconductor released Bare Metal version of the nRF Connect SDK for nRF54 devices which makes use of CMRX on these microcontrollers possible.
6. The CMRX hosted environment runs on Linux. It was tested on x86_64 platform. As of now, this environment lacks support for memory isolation.

Additionally CMRX can be run on any auxiliary CPU core in SoCs which is Cortex-M0+ or better and supports ARM Cortex-M MPU.