[geeks] SATA Drives and Delay Start

[Lionel Peterson]

>From: Sridhar Ayengar <ploopster at gmail.com>
>Date: 2008/03/05 Wed PM 04:59:32 CST
>To: The Geeks List <geeks at sunhelp.org>
>Subject: Re: [geeks] SATA Drives and Delay Start

>Jochen Kunz wrote:

<snip>

>> RTFWP: (Read The F* WikiPedia ;-) )
>> http://en.wikipedia.org/wiki/Serial_ATA
>> http://en.wikipedia.org/wiki/Staggered_spinup
>
>I've read both of those articles, but I'm still confused.  The SATA 
>power connector to which the drives will be attached are coming directly 
>from the power supply.  I don't see a way of attaching a SATA pwoer cord 
>to the controller, and, in any case, I doubt the controller would be 
>capable of gating that much power.

Quote:
"It requires a feature called Power Up in Standby (also called PM2) in both the hard drives and the computer's BIOS, as this option keeps the hard drives from spinning up when receiving current, waiting for the staggered spin-up"[0]

Which I read as meaning the drive need to support it, and the computer needs to act a certain way. It appears that this is a two-part process, the drive knows to lok for a certain condition before spinning up, and the BIOS exerts a control signal once it is up and running. Again, the model in my mind would be a line held in a certain state that does not occur by default (high?), and is brought low by by the controller in a prescribed manner if a certain option enabled in the firmware. In this canse the firmware overrides the default nature of the hardware. 

Lionel

[0] http://en.wikipedia.org/wiki/Staggered_spinup