#74LS148

Description: Priority Encoder 3 to 8 cascadable

Datasheet: http://www.ti.com/lit/gpn/sn74LS148

Pinout:

    +-----------+
 I4 |[ 1]   [16]| VCC
 I5 |[ 2]   [15]| EO
 I6 |[ 3]   [14]| GS
 I7 |[ 4]   [13]| I3
 EI |[ 5]   [12]| I2
 S2 |[ 6]   [11]| I1
 S1 |[ 7]   [10]| IO
GND |[ 8]    [9]| S0
    +-----------+