create a test field, type short. 
apply this code in field calculator:
1 - choose "python" as a parser:
2 - check show block:
3 - write these line in pre-logic text-box: `
def test(a,b):
 if a==b:
  return 1
 else:
  return 0
`4 - at the last text box write this line:`
test(!field1!,!field2!)
`5 - Field1 and field2 should be your two field to be compared:
6 - Then you can find the different values on test field, rows with number 1 are same and the rows with 0 are different: