Raspberry Pi questions

[Tim Kientzle]

On Dec 26, 2012, at 7:03 AM, Ian Lepore wrote:

> 
>> 2) Random failure to mount root.
>> 
>> This is weird.  If I insert the SD card into my Mac and open
>> the MSDOS partition, then eject, the card will boot (sort of,
>> see below).  Otherwise, the kernel can't mount root.  I'm
>> entirely baffled.
>> 
> 
> I had something like this happen several times yesterday.  Most of the
> time it boots fine, sometimes it fails to mount root from the sdcard,
> but then it works on a reboot.  I also saw the mmcsd0 driver ident line
> say the bus was running at 50mhz several times, and I'm pretty sure I
> wasn't using any SDHC cards, but that also wasn't the problem I was
> pursuing so I didn't pay close attention.
> 
> Of course, that doesn't seem to intersect with what you describe very
> much at all, unless touching the card on the Mac wasn't really a cure,
> it was just some misleading coincidence going on.

Apparently it was just coincidence (that happened two times in a row!).

I just tested a few more times and it now mounts root or not
randomly even without mounting elsewhere in the middle.

But I do see the correlation with probing the card at 25MHz (works)
or 50MHz (fails).

Tim