AT91SAM Low Power Modes

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Does anyone have any experience with Atmel's AT91SAM9 microcontrollers? I'm working with an eval kit for the AT91SAM9XE512 trying to exercise the processor low power modes but am not having much success. More specifically, there is a mode advertisted in the datasheet's electrical characteristics section called "Ultra low power" that purports to draw only 600uA on VDDCORE supply lines. The best I've been able to get is about 1.1mA, plus it takes several seconds to "wake up" to full power operation after I press a button on the eval board that I have configured as an interrupt source. 1.1mA seems too high and a several second wake time seems excessive when I can just reset and reconfigure the processor in under 1 second.

Does anyone have any experience in this arena or know of any good resources for it? Atmel tech support has been slow to respond although they did provide an example project for AT91SAM9261 processors which I ported to the 9XE to no avail.

Thanks in advance!

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I had worked with SAM7S/X, but never with SAM9. But I found www.at91.com quite useful for many Atmel ARM powered uC questions.

Guillem.
"Common sense is the least common of the senses" Anonymous.

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Hi,

I suppose that the low power mode means that you cut core power supply and you just keep the back area active. Did you check that ?

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Quote:
Hi,

I suppose that the low power mode means that you cut core power supply and you just keep the back area active. Did you check that ?

By low power mode I mean I want to be able to put the CPU into some state where it isn't executing (or executing very slowly) such that it draws minimal power. I don't plan on actually cutting off any power supplies as I'd like to preserve SRAM contents for a fast reaction time after some external event wakes the system. Put another way, I don't want to use the shutdown controller (SHDWN in the datasheet).

Guillem: I've looked at www.at91.com but wasn't able to find any information. I'd have posted something myself but the forum registration system appears to be broken.

For an update, I've reduced wakeup time significantly, but still haven't realized the low power consumption that that datasheet advertises.