From: Paul Suade <paul.suade_at_laposte.net>
Date: Mon, 26 Aug 2002 14:15:27 +0200

I made a mistake about sleep and standby modes. Because those offered by IDE
commands (HD) are inversely defined. So sleep mode is perfectly right and
standby mode too troublesome as you say to use.

----- Original Message -----
From: "Daniel Stenberg" <daniel_at_haxx.se>
To: "Rockbox" <rockbox_at_cool.haxx.se>
Sent: Monday, August 26, 2002 9:39 AM
Subject: Re: Re: time to sleep?


> On Sat, 24 Aug 2002, Paul Suade wrote:
>
> > Just a precision, you were speaking about sleep mode, it is a mistake,
you
> > probably speaking about standby mode. Don't use sleep mode but standby
mode
> > to reduce the power consumption because sleep mode shuts down all, i.e,
> > peripheral controlers like timers, external interrupts would be reset,
which
> > is probably not what you want.
>
> Are we talking about the same CPU here? "Hitachi SH-1 Hardware Manual
r5.0"
> section 19.1.1 explains the two modes "Sleep" and "Standby".
>
> And yes, reading this again now, I still think Sleep is the mode we want
to
> use. Standby seems to be more troublesome to use, even if consumes far
less
> power.
>
> Again, Sleep reduces CPU power consumption by about 33% "typcial". I think
> that is enough to motivate usage of it.
>
> Standby goes down to whopping 0.1uA but is harder to awake from and plays
> more tricks with clocks and I/O ports etc. But of course, if you can make
> good use of the standby mode, I'll be very happy!
>
> --
> Daniel "Bagder" Stenberg -- http://rockbox.haxx.se/
>
Received on 2002-08-26