C0h is the code (in hex, that's what the h is) that you need to send to address a particular slave, in this case, one whose address is 0 (A0, A1, and A2 all zero). If you look at 6.1 Device Address in the data sheet, you will see that the register has a fixed part, the 7th and 8th bits, that are set to 1; that would equal 192 or C0 in hex.
I can't use the symbols like "BLINK" and "PWM0" or anything, right? I have to select the address and then send the bits, right?
That is correct.