Yes, it only applies to ALL of the pins on the expansion headers. All SOCs
have a specific power sequencing and this is related to that. You can read
more about it in the AM3358 and TPS65217C datasheets.

There are no high impedance pins on the AM3358. See previous sentence.

Gerald


On Tue, May 27, 2014 at 5:43 AM, PLyttle <[email protected]> wrote:

>
> When Gerald Coley wrote that down, he must have meant just that. He wrote
> it in big red capitals, so he must have REALLY meant it.
> ANY I/O pin is not equal to SOME I/O pins
>
> By the way If you don't (want to) believe the SRM, why would you trust
> something said in a forum on the matter? This has come up a few times. You
> can look it up.
>
> If you choose to remain agnostic on the matter you can also just read
> the Revision A5.2 version of the SRM, where this statement is missing, so
> you could make a case that you are right.
>
> On Tuesday, May 27, 2014 11:18:27 AM UTC+2, James Lim wrote:
>>
>> According to the SRM page 94:
>>
>> DO NOT APPLY VOLTAGE TO ANY I/O PIN WHEN POWER IS NOT SUPPLIED TO THE
>> BOARD.
>> IT WILL DAMAGE THE PROCESSOR AND VOID THE WARRANTY.
>> NO PINS ARE TO BE DRIVEN UNTIL AFTER THE SYS_RESET LINE GOES HIGH.
>>
>> I hope to have a deeper understanding on that statement. Does that only
>> apply to specific pins such as the boot config pins?
>>
>> My application requires beaglebone to be a secondary processor and it
>> communicates with the primary processor using I2C and SPI. The beaglebone
>> will bootup and shutdown occasionally while the primary processor will be
>> on all the time.
>> I am under the impression that the pins on the beaglebone should be on
>> high impedance when beaglebone is powered down. With I2C pulled up by
>> default and assuming I did attempt to drive the SPI bus when BBB is powered
>> down, is that going to destroy the processor?
>>
>>
>  --
> For more options, visit http://beagleboard.org/discuss
> ---
> You received this message because you are subscribed to the Google Groups
> "BeagleBoard" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> For more options, visit https://groups.google.com/d/optout.
>

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to