[PATCH RFC 0/4] Add set_iofv() callback

Michael Walle michael at walle.cc
Tue Nov 14 02:05:38 PST 2023


Hi Biju,

>> But that really begs the question why the Atmel flash isn't
>> working with that setting. I suspect some problems during the turn 
>> around
>> of the direction of IO3.
>> You'd really have to probe with an oscilloscope though.
> 
> OK, but as per [1], 8.14, IO3 must be HiZ for Atmel flash.

Sure, but the question is *why*? The flash shouldn't drive IO3
during the command phase. Also, because it might be in HiZ it
cannot read the state (as it is undefined at this point). So
what is going wrong here?

As mentioned, I suspect something is going wrong during the
change of direction of the IO3 line. Either the SoC is driving
it for too long, or the flash is driving it too early?

-michael



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