the control of a common select input (S). The four outputs present the selected data in the true (non-inverted) form. The enable input (E) is active LOW. When pinEis HIGH, all of the outputs (1Y to 4Y) are forced LOW regardless of all the other input conditions. Moving the data from two groups of registers to four common output buses is a common use of the 74LVC157A. The state of the common data select input (S) determines the particular register from which the data comes. It can also be used as function generator.