+---+--+---+ +---+---+---+---*---+ 1Y |1 +--+ 14| VCC | A | B | C | D | Y | Y = ABCD 1A |2 13| 2Y +===+===+===+===*===+ 1B |3 12| 2D | 0 | X | X | X | 0 | 1C |4 4082 11| 2C | 1 | 0 | X | X | 0 | 1D |5 10| 2B | 1 | 1 | 0 | X | 0 | |6 9| 2A | 1 | 1 | 1 | 0 | 0 | GND |7 8| | 1 | 1 | 1 | 1 | 1 | +----------+ +---+---+---+---*---+