I2C Read/Write problems

[JD123]

I guess that's what I'm saying here...is that PBP handles it for us.

No. it doesn't. PBP handles the R/W bit for us. We still have to give it the correct address, formated to the device address byte. That's why you send %10100000 and the reciever "sees" %01010000 as the device address.

Now, if the receiving device specs say "send $xyz" then they have already formated the address for you. That still doesn't change the fact that the address is the upper 7 bits shifted right one place.