MPC823: i2c-algo-8xx read interrupt?

[Pergola, Michael]

	>> The way I interpret the data sheet (I assume the 823 and 860 are
similar) is that I get the TX
	>> interrupt when the I2C address is sent plus the two character
times. The rest of the TX buffer
	>> is just a place holder and will not be sent.

	>Not correct.  The data isn't sent on the data lines, but the CPM
decrements the
	>counter and uses it to time the receive transfer.  The I2C thinks
it is sending
	>something, but the bits just fall off the sand into a bucket.  It
is used to generate
	>the timing of the clock and count how many receive bytes you wish
to acquire.

According to the MPC823e User's Manual:

"The I2C receiver and transmitter are double-buffered, which corresponds to
an effective
FIFO size of 2 characters. The MPC823e I2C bit 0 (MSB) is shifted out
first." pg. 16-456

I interpret this to account for the additional two character clock times
you'll need to do.

Just my $.02,
     Michael Pergola
     Software Engineer
     Baltimore, MD  21236     (410) 931-6778 x4259


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