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Date:      Thu, 7 Jun 2007 12:46:37 -0700 (PDT)
From:      Neil Bradley <nb@synthcom.com>
Cc:        arm@freebsd.org
Subject:   Re: 4-bit SD Card mode
Message-ID:  <20070607123930.E75948@synthcom.com>
In-Reply-To: <20070607.133456.74668036.imp@bsdimp.com>
References:  <50392.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181235257.squirrel@webmail.alpha-tierchen.de> <20070607180946.GK16463@cicely12.cicely.de> <49754.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181244172.squirrel@webmail.alpha-tierchen.de> <20070607.133456.74668036.imp@bsdimp.com>

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> I'm not sure I like this at all.  The devices shouldn't be setting up
> the pins for that device.  In some cases, they can't know how to do
> that, and this is one of them.  The device has no way of knowing if
> all 4 wires are connected, or just 1 and the 'spare' lines are used
> for GPIO.

Not doing it will irritate more people (i.e. "I'm not getting full speed 
out of the SD card). While it's a valid concern, I don't think it's 
unrealistic to assume that all 4 DAT lines are hooked up. I've not yet 
encountered a design that A) had SD capabilities, B) was only running 
single bit because of a lack of GPIOs.

-->Neil

----------------------------------------------------------------------------
C. Neil Bradley - KE7IXP - The one eyed man in the land of the blind is not
                            king. He's a prisoner.



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