Re: [Contiki-developers] Tmote sky low-power modes

[Bjorn G. <bg...@si...>]

On Fri, 10 Oct 2008 15:34:33 +0100
"Jonathan Lewis" <jo...@cs...> wrote:

Moi,


> After looking at the M25P80 manual I suspect your code is doing what
> it is supposed to and the change in current use is merely very
> small. As far as I can tell from the manual, with the chip-select
> driven high (happens at xmem_init and after spi_flash_disable) the
> chip will go into stand-by mode when there is nothing to
> do. Assuming the M25P80 is going into stand-by mode then the change
> in current use between standby mode and deep sleep mode is only
> around 40__A, which is roughly what I am seeing.

A pity that the saving is so small, anyways thanks for testing the
code.

> So probably everything is working and thank you very much again.

One more thing, did you check if the signature returned matches
M25P80_SIGNATURE?

> My hunt for the guilty power drainer will continue and I'll let you
> know if I manage to achieve low __A current use for the TMoteSky
> board.

Did you try to disable the sht11 and the light sensors?

> Purely, out of interest, if it were possible to turn the chip off
> completely, would the line look something like P4OUT &=
> ~BV(FLASH_PWR); ? I merely ask, as I may want to do this for other
> chips on the board.

Yes, that should do the trick.

Have a nice weekend,
/b

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Bjorn Gronvall (Björn Grönvall)                    /_______________/|
Swedish Institute of Computer Science              |               ||
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