Does Wakeup reset RAM values ?

inaki

When I exit from SLEEP mode, RAM variables are preserved ?
Does Wakeup have the same effect as a RESET ?

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Bean

Download this application note. It explains it.

http://www.parallax.com/dl/appnt/sx/An18Reset.pdf

Bean

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inaki

Thanks Bean.

I understand by this document that on a SX28AC wakeup process takes about 18ms and SRAM is preserved.
I think this may work well for my project. Thank you!

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dkemppai

inaki said...
Thanks Bean.

I understand by this document that on a SX28AC wakeup process takes about 18ms and SRAM is preserved.
I think this may work well for my project. Thank you!

FYI, Be careful when looking at the pin data. This can get messed up on a wakeup. Note, it says that it's the same,
but in some cases it may change states on you. Notice the direction registers on wakeup, and then watch your pin data
closely. In one of my programs/hardware I found I needed to shadow the pin data before going into a sleep, and reset
that data on wakeup. This 'feature' almost cost a bunch of time and $$$. I've seen reference to this before, but couldn't
seem to find it again.

-Dan


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