First thing I see is
which will not work as expected with an 8 bit wide IDAC.
In the comment is said that value will give 1mA which is difficult for this IDAC.
I changed it into
/* Configure the IDAC to source maximum value*/
my IDAC is an 8-bit. Nevertheless i get wrong values.
The ADC config is not the same as original demo project, please restore ADC config to original status as demo project and try the test again
I changed the Config am some Code but it didn't help. I changed the ADC channel to zero beacuse put an ADC_Mux.
Now I get a constant Value of -242. I think the issue is in the coding. Because I measured the right voltage with my multimeter.