Subject: Re: IDE interfaces without pull-up resistors
To: Ben Harris <bjh21@netbsd.org>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: tech-kern
Date: 06/11/2001 21:28:41
On Sat, Jun 09, 2001 at 11:20:52PM +0100, Ben Harris wrote:
> I've got two different IDE interfaces here that don't have pull-up
> resistors on their data lines.  This means that reads from empty channels
> return the last byte written to that channel (presumably through the
> capacitance of the bus lines) rather than 0xff.  This causes wdcprobe() to
> have to go through the full >31-second reset sequence before it can
> determine that the channel is empty, which gets to be a pain when the
> interface has three channels.
> 
> Would it be OK for wdcprobe() to have the same short-circuit for this case
> as it has for the pull-up resistor case?  Something like:

If this work in your case I think this can be usefull for some other
hardware I've got access to. Please commit it.

--
Manuel Bouyer <bouyer@antioche.eu.org>
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