Latest News Items: FreeRTOS V8 released - FAT file system released - Tick suppression demo'ed SAM4L, RX100 & STM32L
 Real time embedded FreeRTOS RSS feed 
Real time embedded FreeRTOS mailing list 
Quick Start Supported MCUs Books & Kits Visualisation Ecosystem Training Contact & Support




Last site update Jan 14 2014

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.

The behaviour of one-shot timers and auto-reload timers
Timer behaviour when a timer is reset





[ Back to the top ]    [ About FreeRTOS ]    [ Sitemap ]    [ ]




Copyright (C) 2004-2010 Richard Barry. Copyright (C) 2010-2013 Real Time Engineers Ltd.
Any and all data, files, source code, html content and documentation included in the FreeRTOSTM distribution or available on this site are the exclusive property of Real Time Engineers Ltd.. See the files license.txt (included in the distribution) and this copyright notice for more information. FreeRTOSTM and FreeRTOS.orgTM are trade marks of Real Time Engineers Ltd.