In a very general sense: When should you use pull up or down resistors on IC inputs and when should you connect the pin directly to Vcc/GND?
Particularly if no impedance is mentioned for the pin. Or can you assume the impedance to be near infinite so it does not matter?
For example, the TUSB2036. It either doesn't give an impedance for the control pins or I'm not looking in the right places (which is a very real possibility). Do I place a pull-down resistor on the ~BUSPWR pin or do I connect it straight to GND?
The schematics in the data sheet connect it directly, so that gives a strong indication that a pull-down resistor is not needed, but are there other indicators I can use to determine this, in case example schematics are not available for other ICs?
And, if a resistor is necessary (or at least a good idea), but I don't know the impedance — how do I determine the value of the resistor to use?