# Low-Power-Management

**URL:** <https://forums.freertos.org/t/low-power-management/4657>\
**Category:** Kernel\
**Created:** [May 8, 2007, 2:06pm UTC](https://forums.freertos.org/t/low-power-management/4657 "2007-05-08T14:06:55Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\
**Post date:** [May 8, 2007, 2:06pm UTC](https://forums.freertos.org/t/low-power-management/4657/1 "2007-05-08T14:06:55Z")

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**nobody** wrote on [Tuesday, May 08, 2007](https://sourceforge.net/p/freertos/discussion/382005/thread/cc2fe355/#8473):

Hi,

i have running A IAR-MSP430 Port of V4.2.0 with some small extentions for Low-Power-Modes.  
So the System is running in Power-Down with the 32kHz - Clock as a Realtime Clock toggeling ans showing on LCD every second with 10uA current.

For Power-Down I loaded the value of the tik-counter in a timer with the next task-wakeup-time and coroutine-wakeup-time in a Compare-Register of that Timer.

So the Controller can Sleep up to the nextwakeup or asynchron event.

Then the Tik-Counter is restored and the normal Realtime-Tiks are Handled.

If there ist no task or coroutine to run, the Power-Down-Mechanism is Called in the IDLE-task.

I Implemented this in port.c file but I extended the task.c with some small Routines to get and set the TIKs

portTickType&nbsp; xTaskGetxTickCount(void)  
void xTaskSetxTickCount( portTickType newxTickCount )

and to get the next Timepoint to wake up

portTickType xTaskGetNextDelayedTik( void )  
portTickType pxGetNextDelayedCoRoutineTik ( void )

Are there an interest or plans to implement some more low-power-management feature in Free RTOS ?

Jürgen

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**Author:** ![rtel](https://d3iykfbgfh8zhg.cloudfront.net/user_avatar/forums.freertos.org/rtel/32/31_2.png) [@rtel](https://forums.freertos.org/u/rtel)\
**Post date:** [May 8, 2007, 6:07pm UTC](https://forums.freertos.org/t/low-power-management/4657/2 "2007-05-08T18:07:50Z")

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**[rtel](https://sourceforge.net/u/rtel/)** wrote on [Tuesday, May 08, 2007](https://sourceforge.net/p/freertos/discussion/382005/thread/cc2fe355/#8473/85e9):

Hi - Nice work - I would definitely be interested in seeing your modifications.&nbsp; My email address is r [\_dot] barry [\_at] [freertos.org](http://freertos.org).&nbsp;

[attachments get stripped from SourceForge emails].

Regards.

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**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\
**Post date:** [May 13, 2007, 7:06pm UTC](https://forums.freertos.org/t/low-power-management/4657/3 "2007-05-13T19:06:16Z")

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**nobody** wrote on [Sunday, May 13, 2007](https://sourceforge.net/p/freertos/discussion/382005/thread/cc2fe355/#8473/85e9/67cd):

Hello.  
I also will be glad to seeing Your modification. My

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**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\
**Post date:** [May 14, 2007, 10:53am UTC](https://forums.freertos.org/t/low-power-management/4657/4 "2007-05-14T10:53:59Z")

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**nobody** wrote on [Monday, May 14, 2007](https://sourceforge.net/p/freertos/discussion/382005/thread/cc2fe355/#8473/8e60):

I too would like to see your implementation of low power management, please send to frankwa [\_at][gmail.com](http://gmail.com)

Best regards, Frank Andersen