AnsweredAssumed Answered

TWI/I2C repeated start mode problem

Question asked by edsut on Mar 24, 2010
Latest reply on Oct 13, 2013 by Sudhanshu


First, I apologize if this subject is already under discussion.  I didn't see any easy way

to search the discussion topics.

Anyway, I'm working with a BF537 and have interfaced to several (i.e. 4-5) different

I2C devices already.  The latest device has a requirement that is slightly different than

any others in the past...

To read from the device I need to use repeated start mode, where I first write 3 bytes of

data, then repeat the start and expect to read back 2 bytes of data.

I have connected to devices using repeated start in the past, but have never had the

need to send more than 2 characters in the 'write' burst prior to the read.  What I am

finding is that I can't send more than 2 characters because the transmit fifo doesn't

appear to be emptying.  After 2 characters are loaded into the fifo, my code times out

waiting for the XMT_FULL flag to clear in the FIFO status register.


Has anyone done this before?

Any help sure would be appreciated.