The FreeRTOS kernel is now an MIT licensed AWS open source project, and these pages are being updated accordingly.

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FreeRTOS+ Ecosystem

FreeRTOS+TCP:
Thread safe TCP/IP stack

SafeRTOS:
TUV certified RTOS

OpenRTOS:
Commercial Licensed RTOS

Fail Safe File System:
Ensures data integrity

FreeRTOS BSPs:
3rd party driver packages

Trace & Visualisation:
Tracealyzer for FreeRTOS

CLI:
Command line interface

WolfSSL SSL / TLS:
Networking security protocols

RTOS Training:
Delivered online or on-site

IO:
read(), write(), ioctl() interface

FreeRTOS+ Lab Projects

FreeRTOS+POSIX:
POSIX threading API

FreeRTOS+FAT:
Thread aware file system

Software Timers
[More about software timers...]

Resetting a software timer

It is possible to re-set a timer that has already started to run. Resetting a timer results in the timer recalculating its expiry time so the expiry time becomes relative to when the timer was reset, and not when the timer was originally started. This behaviour is demonstrated in the next diagram, where Timer 1 is a one-shot timer that has a period equal to 5 seconds.

In the depicted example, it is assumed that the application switches on an LCD back-light when a key is pressed, and that the back-light remains on until 5 seconds pass without any keys being pressed. Timer 1 is used to switch off the LCD back-light when this 5 seconds has elapsed.