I really don't know. What is that ? I have a two wire RTD.
the RTD is a PT1000, which means that at zero degrees celcius its resistance will be 1000 Ohms.
At that point A0 and A1 should read the same voltage and the difference will be zero.
I measure A0 and A1, what I calculate is the resistance on the RTD to know its value according to environment temperature. Then using a lookup table, I find the temperature that corresponds to that resistance value