Test RND, FIX and ENG display from 20 of original manual enhanced by some alpha output so that one can easily see if the test was successful.

 ***P0
        AC 100 ÷ 6 = RND4 “1.667E 01=#?“ HLT FIX5 “16.66667=#?“ HLT AC 
 ***P1
        AC 200 ÷ 7 = FIX3 “28.571=#?“ HLT × 14 = “399.994=#?“ HLT AC 
 ***P2
        AC 123 × 456 = ENG ENG “56.088E 03=#?“ HLT AC 7.8 ÷ 96 = ENG ENG “81.25E-03=#?“ HLT AC