I want to use the SN65HVD31DR to connect two microcontrollers together. The connecting cable has an impedance of Z0 = 80Ω. According to the data sheet it is recommended to terminate the connection cable on both sides. So there would be two 80Ω resistors connected in parallel which would effectively make a parallel resistance of 40Ω. According to the datasheet the differential load resistance RL must not be less than 54Ω.
So is it right that I am not allowed to terminate the connection line with two 80Ω resistors and I have to use a cable with a higher impedance so I can use higher termination resistors? Or do I misunderstand something?