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Date: Thu, 22 May 2014 11:34:50 -0300
Message-ID: <CAB=2f8xyzLQpTQgwc8EHh-_A-0HV_H3w_7uW_RAYXM8X_Q02MA@mail.gmail.com>
Subject: Re: BBB MMC / SD detection instability with U-Boot 2014.04 (CPU 1GHz)
From: Luiz Otavio O Souza <lists.br@gmail.com>
To: SAITOU Toshihide <toshi@ruby.ocn.ne.jp>
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Cc: "freebsd-arm@freebsd.org" <freebsd-arm@freebsd.org>,
 Ian Lepore <ian@freebsd.org>
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Just picking one email to reply...

This is probably unrelated, but i can consistently corrupt my SD Card
data if i connect (and use) a very small R/C servo (the 9g ones, used
on foam planes) to the 3.3v on the expansion headers.

I'm not sure if it is because of noise or the power consumption, but
looks like the BBB is really picky about the power conditions here.

Connecting the servo to the VDD_5V on the same header makes the problem go away.

So be careful about what you connect on your boards :)

Regards,
Luiz