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From: Albert ARIBAUD <albert.aribaud@free.fr>
To: u-boot@lists.denx.de
Subject: [U-Boot] OMAP3 Beagle Pin Mux initialization issue
Date: Fri, 25 Feb 2011 23:23:34 +0100	[thread overview]
Message-ID: <4D682BE6.2060805@free.fr> (raw)
In-Reply-To: <4D6822CC.406@prodigy.net>

Le 25/02/2011 22:44, Bob Feretich a ?crit :

> For the BeagleBoard, the pins of interest are the ones routed to the
> Expansion, J4, and J5 connectors. I am working with a local university.
> Students are building projects that interface to these connectors.
> Usually, the Linux boot delay is not a concern, but depending on the
> project, sometimes the pins need to be initialized before a "set time
> interval after power-on" expires (We can set the power-on reset delay to
> several hundreds milliseconds, but the time must be bounded.)

Can you not simply set this time high enough that the U-Boot script 
executes?

> By having the spot (beagle.c&  beagle.h) in u-boot, where we can add our
> I/O Pin Mux initialization code, we can satisfy the needs of a bounded
> I/O initialization time.

Out of sheer curiosity (I've done some lab teaching in assembly language 
and device control in a previous life), what are those IOs that have 
such a bounded set-up time relative to power-on in a university project? 
If you are willing to answer but find that's really not related to 
U-Boot, we can discuss this in private.

> Regards,
> Bob Feretich

Amicalement,
-- 
Albert.

  reply	other threads:[~2011-02-25 22:23 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-02-22  1:51 [U-Boot] OMAP3 Beagle Pin Mux initialization issue Bob Feretich
2011-02-22  7:28 ` Wolfgang Denk
2011-02-25 21:44   ` Bob Feretich
2011-02-25 22:23     ` Albert ARIBAUD [this message]
2011-02-25 22:24       ` Albert ARIBAUD
2011-02-26  6:25       ` Bob Feretich

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