FreeRTOS Version 10

Backward Compatibility

FreeRTOS V10 contains a new source file, stream_buffers.c, and for consistency has renamed the StackMacros.h header file stack_macros.h. However, V10 is a drop-in compatible replacement for FreeRTOS V9.x.x, as the new source file is only required to enable new features, and two copies of the changed header file are provided – one with the old name and one with the new. stack_macros.h is only used internally within the FreeRTOS kernel code.

Introducing Stream Buffers and Message Buffers

FreeRTOS 10 contains two significant new features: Stream Buffers and Message Buffers.

Stream Buffers are an inter process communication (IPC) primitive optimized for use in scenarios where there is only one reader and only one writer, such as sending a stream of data from an interrupt service routine (ISR) to an RTOS task, or from one processor core to another.

Message Buffers build on top of Stream Buffers. Whereas as Stream Buffers send a continuous stream of bytes, Message Buffers send discrete messages that can be of varying length.

Other Changes

See the change history for more details of new ports and other enhancements.

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Latest News

FreeRTOS v10.2.1 is available for immediate download. MIT licensed, includes 64-bit RISC-V, NXP Cortex-M33 demo & Nuvoton Cortex-M23 demo & STM32H745 dual core (AMP) demo.

New MIT licensed IoT MQTT and IoT Task Pool libraries now available. Includes demo projects.

View a recording of the “OTA Update Security and Reliability” webinar, presented by TI and AWS.


FreeRTOS and other embedded software careers at AWS.

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