Olin Lathrop wrote:
> Bob Axtell wrote:
>   
>> But powerup does NOT place
>> the device in a known state.
>>
>> ...
>>
>> If the SDA cannot be freed after 9 clocks, you either have
>> another master driving the bus, or you have a defective i2c device on
>> the bus.
>>     
>
> Or what if a device powers up in the clock stretch slave state?  If the
> power up state is truly unknown (where did you see this?) then how do you
> know it isn't holding clock low, in which case you can't clock the bus and
> can never enter normal operation?
>
>
> ******************************************************************
> Embed Inc, Littleton Massachusetts, (978) 742-9014.  #1 PIC
> consultant in 2004 program year.  http://www.embedinc.com/products
>   
I've never seen slave stretch hold SCK low at power up. In fact I've 
never used an I2C  device
that implemented the clock stretch state. Even Smart Batteries don't 
implement it.

I guess that's possible, but its a stretch....<g>. Have a great day.

--Bob
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