Re: HDD LED doesn't light.

Adrian Yee
2004-08-31T19:46:54Z

> Just an FYI... historically, the LED has been driven in PATA with a
> signal known as /DASP, this is an active-low signal called "Drive
> Active / Slave Present" and a PATA drive asserts this signal when
> processing a command.
>
> If I understand it right, in SATA, instead of a wire-based protocol,
> we have a serialized packet-based protocol, so there was no driving
> of
> an LED in the initial specification. Revisions to the specification
> have since commandeered one of the pins on the power connector for
> use
> as a /DASP signal to drive an LED. However, to do that you
> obviously
> can't be using a MOLEX->SATA power adapter, you need a motherboard
> that natively supports SATA. The 3112 you mention attempts to be a
> native SATA solution, it doesn't act merely as a PATA->SATA
> converter.
> Therefore, they may not have done the DASP- signal internally.

But this doesn't explain why I have two motherboards here where the HDD
activity LED does not light up in linux (for SATA drives) but does in
windows . Note that it only starts working in windows *after* the
driver has loaded. One is an ASUS A7N8X Deluxe (rev 1.0) and the other
an Abit NF7-S (rev 2.0), both with Sil3112 controllers. On the other
hand, I have a DFI Ultra Infinity with a Sil3114 whose activity LED
works fine in linux.

Adrian