From: Jens Arnold <arnold-j_at_t-online.de>
Date: Sun, 04 Jul 2004 00:15:53 +0200

Hello Pedro,

> I would just like to ask exactly what does the "Disk Poweroff"
> setting do.

The v1 Recorders have the ability to physically switch off the
DC power to the hd independent from the rest of the box.

If "disk poweroff" is set to "no", the disk gets only switched
into standby mode by an ata command when it is not needed.
It does still consume some DC power in this mode.

If "disk poweroff" is set to "yes", Rockbox cuts the disk's DC
power after switching it into standby mode, saving the standby
power consumption. The drawback of doing so is that the disk
needs a bit longer to spin up from off state than from standby,
but overall this yields a bit more battery runtime.

> Still, i did changed to "Yes" and run the usual tests.
> Actually, it's still on as i continue to use my box daily.

A short explanation why I asked you to do this: As I explained
above, when "disk poweroff" is set to "yes", the disk is
switched off completely any time it is not needed. Some of the
disk's settings are volatile, so they have to be redone each time
the disk is powered on again, not only at Rockbox' startup as if
"disk poweroff" was set to "no".

There was a slight chance that these settings would not be redone
completely on each disk poweron due to oversights in the code,
what may cause file system corruption in conjunction with the
fast ata routines if an important setting would be missing.

> I also did the rename and boot to archos fw.

> Both tests worked fine, with no corruption whatsoever!

This is very good news indeed. I will discuss with Linus asap if
we could enable the fast ata routines for everyone now.

> And thanks for all the hard work, yours and everyone elses!

I have to thank you for doing all those extensive testing, since
obviously I cannot do that myself, as I have neither a V1
Recorder with hardware mask 0x0102 nor a Hitachi DK23CA
harddisk, the only hardware combination that seems to have had
these problems with file system corruption back then.


Regards, Jens

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Received on 2004-07-04