I am trying to use LTC6804-2 chips to measure and monitor 20 battery cells. So far I have had success using a single LTC6804-2 chip to measure 12 out of 20 of the cells. I am using the 4-wire interface and a digital isolator that has its own isolated ground and voltage to isolate the signals for each chip. My issue is that when I connect both LTC6804-2 chips to my MCU and try to communicate with either, using the addressable ports, the response on my MISO line is 0xFF all the way through. Communicating individually with each of them using their address' (0 and 1) work however.