Comparator Negative Input Selection

The NCH bits direct an analog input pin and internal reference voltage or analog ground to the inverting input of the comparator:

NCH	Negative Input Source
111	V_SS
110	FVR_Buffer
101	CxNCH not connected
100	CxIN4-
011	CxIN3-
010	CxIN2-
001	CxIN1-
000	CxIN0-

Important: To use CxINy- pins as analog input, the appropriate bits must be set in the ANSEL register and the corresponding TRIS bits must also be set to disable the output drivers.