WC8 I2C related user guide updated

Does the I2C code as implemented, support any form of master contention?
I'm considering making another board (like the webamp, but different) with a chip, perhaps several, that will communicate via I2C.
One option will be to permit them to talk to other devices on the I2C bus - but this will require both/all the masters to understand they may not be the only master, and to play nice. The standard specifies how this happens, I just need to know if the WC8 does or not :)
 
(In short, one of the things I am frustrated by is the low frequency signals from the anemometer. In order to get good transient response (for wind gusts) I need to monitor quickly. But with an input that may only be 0.4Hz, it's impossible to get decent precision. To address this, I'm going to add another chip that will measure the TIME between pulses). It will also give me the opportunity to include additional counters for such things as a rain-gauge and perhaps other devices. Building a complete "I2C Weatherstation" becomes possible - but with only one I2C bus, I would need to be a "master" at least some of the time.
 
Ross,
 
There some arbitration logic in WebControl I2C master code.  However, that is not fully tested, since we really want to see some real world contention case to test out our arbitration logic. It basically detects the bus busy then hold back little bit with a time delay.  If after delay still could not gain control of the bus, it will return an error flag.  
 
In WebControl PLC calls, there is no place to set error flag, so that we may use zero flag to indicate error condition.  That set zero flag logic is not in the firmware, since we do not want to impact PLC logic flow without hearing from some feedback from users.
 
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