Press a button and the value will be displayed., no more then one button i have not made it add or subtract.
The Binary to Decimal is a copy of EMX451 circuit Binaro_a_Decimal.
Button order :
Hex Decimal
1 2 3 01 02 03
4 5 6 04 05 06
7 8 9 07 08 09
A B C 10 11 12
D E F 13 14 15
