attiny2313A power down mode

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Hi Guys,
I am trying to put an attiny2313A into power down mode.

The datasheet gives me two options (they are both the
same)

Must be a mistake in the datasheet

OR

am I missing something obvious?

Does anyone know which one is correct?

I am certain that I am using the latest datasheet.

Thanks in advance

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Looks like it's not wrong.

 

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Yes but which is it 01 or 11? You can't have both.

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Why can't you have both? It's basically saying that if SM0 is set then SM1 is ignored. Just SM0=1 alone is enough to say "Power Down". If SM0=0 then SM1 selects between Idle and Standby.

 

It's known in the trade as "redundancy"

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This is from another attiny datasheet:

 

There. Easy, no guessing games.

 

Why can't it be straightforward?

 

Then it would be too easy.

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This is not rocket science! Surely you've heard of redundancy?

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There is no ADC on the ATtiny2313, hence the two values being used to enter the same power-down state.

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According to the datasheet I can use the following:

 

SM1 = 0, SM0 = 1 = Powerdown Mode

or

SM1 = 1, SM0 = 1 also = Powerdown Mode

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Yes. Just ignore the fact that SM1 even exists. If you set SM0 to 1 then it will be power down and what SM1 happens to be at that time does not matter. It is "redundant".

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newbie123 wrote:

Must be a mistake in the datasheet

OR

am I missing something obvious?

newbie123 wrote:
According to the datasheet I can use the following:

Did you notice that the datasheet addresses your initial question(s)?

7.1.2 Power-Down Mode

When the SM1:0 bits are written to 01/11, the SLEEP instruction makes the MCU enter Power-down mode.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

Last Edited: Fri. Dec 13, 2019 - 12:34 PM
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theusch wrote:

 

Did you notice that the datasheet addresses your initial question(s)?

7.1.2 Power-Down Mode

When the SM1:0 bits are written to 01/11, the SLEEP instruction makes the MCU enter Power-down mode.

I get it now, it would have been obvious if they were more specific in explaining SM1.

 

Thanks to all who responded to my post!