After reading thru the datasheet section on the MSSP modules, I'm sure it's my error in not setting something in the MSSP up properly. I will have to get down and really figure out what all these setup bits actually do when I get back in front of hardware later today. My first post was a little misleading by saying the second I2C port 'worked'. It returned '0', but there wasn't any hardware on the buss either. It also did not work with hardware on the buss. It just kept returning '0's. That points away from hardware (I've used this PCF8574's for years, and the hardware is connected right). It's the dummy driving the new PIC that's at fault. :-(
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