74857
12-to-6 line inverting/noninverting data selector/multiplexer with masking
and zero detect.

      +----------+
   S0 |1  +--+ 24| VCC
  1A0 |2       23| S1
  1A1 |3       22| 6A0
   1Y |4       21| 6A1
  2A0 |5       20| 6Y
  2A1 |6   74  19| 5A0
   2Y |7  857  18| 5A1
  3A0 |8       17| 5Y
  3A1 |9       16| 4A0
   3Y |10      15| 4A1
   ZD |11      14| 4Y
  GND |12      13| COMP
      +----------+

[This information is part of the GIICM]