Hi
I have checked everything but it does not work.
I have AVDD and IOVDD = 3.3 V.
When it comes to ADCVDD and DVDD I have tried both with internal regulator and also an external 1.8V.
REFOUT is connected together with REFIN with the recommended capacitors.
I also have a crystal on 8.192 MHz https://www.elfa.se/elfa3~eu_en/elfa/init.do?item=74-516-36&toc=0&q=LF+XTAL003271.
I do not know what do you mean by VREFF but REFGND is grounded with all the other points that needed to be grounded.
I have tried with different power supply but keep getting the same answer.