#74LS181

Description: Arithmetic logic unit

Datasheet: 74xx/74F181.pdf

Pinout:

    +-----------+
 B0 |[ 1]   [24]| VCC
 A0 |[ 2]   [23]| A1
 S3 |[ 3]   [22]| B1
 S2 |[ 4]   [21]| A2
 S1 |[ 5]   [20]| B2
 S0 |[ 6]   [19]| A3
 CN |[ 7]   [18]| B3
  M |[ 8]   [17]| Y
 F0 |[ 9]   [16]| CN+4
 F1 |[10]   [15]| X
 F2 |[11]   [14]| A=B
GND |[12]   [13]| F3
    +-----------+