74181, 40181 4-bit 16-function arithmetic logic unit (ALU) +----------+ /B0 |1 +--+ 24| VCC /A0 |2 23| /A1 S3 |3 22| /B1 S2 |4 21| /A2 S1 |5 20| /B2 S0 |6 74 19| /A3 CIN |7 181 18| /B3 M |8 17| /G /F0 |9 16| COUT /F1 |10 15| /P /F2 |11 14| A=B GND |12 13| /F3 +----------+ [This information is part of the GIICM]