#74LS348

Description: 8 to 3 lines Priority Encoder

Datasheet: http://www.ti.com/lit/gpn/sn74LS348

Pinout:

    +-----------+
  4 |[ 1]   [16]| VCC
  5 |[ 2]   [15]| E0
  6 |[ 3]   [14]| GS
  7 |[ 4]   [13]| 3
 EI |[ 5]   [12]| 2
 A2 |[ 6]   [11]| 1
 A1 |[ 7]   [10]| 0
GND |[ 8]    [9]| A0
    +-----------+