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Date: Wed, 30 Nov 2005 05:12:30 -0500
From: Gregg Nemas <gnemas@gmail.com>
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Subject: Setting IDE mode to PIO for compact flash
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I have a compact flash connected to a PPC440GP processor in "true IDE"
mode. The DMA signals are not connected, so the device must be used in
PIO mode.

However, when I issue hdparm -i, it indicates that the current mode is
DMA mode mdma2, and I think this must be why I am getting "lost
interrupt" messages. Unfortunately, when I try to set the mode to PIO
using "hdparm -p1" or "hdparm -X9", it seems to have no effect.

What do I need to do to get the drive to be set to use PIO?

I amusing linux 2.6.12.3.

Thanks.

Gregg