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Thread: : i2c Master Timing Problems
face picon face BY : Olin Lathrop email (remove spam text)

> > There is a bug in the MSSP where the master samples the ACK bit on the
> > falling instead of rising edge of SCK.  This can cause a race condition
> > where the master sees a NACK instead of ACK.  However, this bug
> > keep the slave from seeing the address byte.
> >
> Thanks for the info, Olin.  What should the master do
> as a workaround, just blast the address then wait
> to read some 8-bit "ACK" back from the slave?

No, that won't work because the master will get a NACK from the slave after
sending the address byte, and therefore give up.  The workaround is to put a
capacitor on the data line to slow it down with respect to the clock.  This
was discussed a month or two ago.  Check the archives.

Olin Lathrop, embedded systems consultant in Devens Massachusetts
(978) 772-3129, olinKILLspamspamKILLspamembedinc.com, http://www.embedinc.com

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<001101c08b15$231cadb0$260bf6cd@pc> 7bit

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