By properly loading the truth table within a cell, that cell can be made to perform any desired combinatorial function. For example, a cell can be configured to act as a wire, or a NAND gate, or a one-bit full adder. A one-bit full adder is shown on the right.
Collections of cells are used to implement higher level functions, such as flip flops, counters, or state machines. As an example, a four bit counter is shown on the right. done