Watchdog and Atmega2560

[rradojko]

Hello!

Using ATmega2560 processor.
How to use a watchdog?

Enable watchdog

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MCUSR = 0x08;

Is that right?

Disable watchdog

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wdt_disable();

Is that right?

Reset watch dog

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wdt_reset();

Is that right?

I wonder whether the commands are correct for the watchdog?

Thanks for the reply.

[dazz]

Hi
i think the WDT enable is as follows

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wdt_enable(WDTO_500MS);

this part of the code below sets the WDT period to 500ms, set it to what you want upto i believe 2seconds which would be (WDTO_2S)

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(WDTO_500MS)

I dont tend to use WDT so havent tested the above
Regards
Dazz

[dazz]

Hi
i think the WDT enable is as follows

wdt_enable(WDTO_500MS);

this part of the code below sets the WDT period to 500ms, set it to what you want upto i believe 2seconds which would be (WDTO_2S)

(WDTO_500MS)

I dont tend to use WDT so havent tested the above
Regards
Dazz

[rradojko]

Hello dazz!

Thank you very much for the answer.

I tested the code on AVR atmega32...

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wdt_enable(WDTO_2S);

This code works, very good ...

Also code for the reset WD works...

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wdt_reset();

Thanks dazz again for the information.

I have another question.
I use procesr ATmega2560 (http://www.atmel.com/Images/doc2549.pdf).
Watchdog has a choice -->>
1:Interrupt
2:System reset
3:Interrup and syistem reset

What would be the code for watchdog the Syistem reset?

Thanks!
rradojko

[dazz]

Hi
If you enable watchdog always on in the config, then the 2560 defaults to the mode you require.

make sure you include a couple of resets to make sure the counter doesnt run over wdt_reset()

Regards
Dazz