Quality RTOS & Embedded Software

NOTE: FreeRTOS Long Term Support (LTS) libraries are now available on Github. Read the What’s New post

FreeRTOS LTS Libraries


FreeRTOS long term support (LTS) releases receive security and critical bug fixes (should any be necessary) for at least two years following their release. That ongoing maintenance enables you to incorporate bug fixes throughout a development and deployment cycle without the costly disruption of updating to a new library version. Long term support is provided courtesy of AWS for the benefit of the entire FreeRTOS community.

The latest LTS release, FreeRTOS 202012.01 LTS, covers the following libraries: FreeRTOS kernel, FreeRTOS+TCP, coreMQTT, coreHTTP, corePKCS11, coreJSON, AWS IoT Device Shadow, AWS IoT OTA, AWS IoT Jobs, and AWS IoT Device Defender.

LTS Status

The following table lists the libraries that are part of the FreeRTOS 202012 LTS release. All meet the LTS modularity and Code Quality Checklist requirements other than the kernel and TCP stack, both of which still comply with their original quality requirements.

Last Updated: 03/01/2021

Library Version Maintained at least until
FreeRTOS Kernel 10.4.3 March 31, 2023
FreeRTOS+TCP 2.3.2 March 31, 2023
coreMQTT 1.1.0 March 31, 2023
coreHTTP 2.0.0 March 31, 2023
corePKCS11 3.0.0 March 31, 2023
coreJSON 3.0.0 March 31, 2023
AWS IoT Device Shadow 1.0.2 March 31, 2023
AWS IoT OTA 3.0.0 March 31, 2023
AWS IoT Jobs 1.1.0 March 31, 2023
AWS IoT Device Defender 1.1.0 March 31, 2023

FreeRTOS LTS Patches

For the latest information, subscribe to Github Notifications by watching the FreeRTOS LTS repository. For the complete list of updates for each patch, view the Changelog.

Patch Version Updates Post
202012.01 LTS Added AWS IoT OTA, AWS Device Defender, and AWS IoT Jobs library to 202012.00 LTS

LTS Code Quality Checklist

The table below documents the LTS release code quality requirements.

# Category Checks
1 Complexity Score All functions will have a GNU Complexity score of 8 or lower
2 Coding Standard All functions will comply with the MISRA coding standard
3 Static Checking All code will be statically checked with Coverity
4 Function Returns All functions will have a single exit point
5 Code Testing All code will have extensive unit tests. Gcov reports will be used to report the test coverage, and each library will have extended functional tests.
6 Requirements Documentation All libraries will have documented requirements, which may include resource requirements, listing all dependencies, and porting requirements (as applicable)
7 Design Documentation All libraries will have a design document, which may include application and cloud interface, state machines, and synchronization (as applicable).
8 Compiler Warning Code will compile without generating any compiler warnings when the gcc -Wall -Wextra compiler options are used.
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