The MC10181 is a highspeed arithmetic logic unit capable of performing 16 logic operations and 16 arithmetic operations on two fourbit words. Full internal carry is incorporated for ripple through operation. Arithmetic logic operations are selected by applying the appropriate binary word to the select inputs (S0 through S3) as indicated in the tables of arithmetic/logic functions. Group carry propagate (PG) and carry generate (GG) are provided to allow fast operations on very long words using a second order look ahead. The internal carry is enabled by applying a low level voltage to the mode control input (M).