Description in VHDL is given by http://www.cs.sfu.ca/~ggbaker/reference/std_logic/src/std_logic_entities.vhd
and for tristate table http://www.cs.sfu.ca/~ggbaker/reference/std_logic/src/std_logic_misc.vhd
Truth Table
| DataIn | Enable | DataOut* |
| * | U | U |
| * | X | UX |
| * | 0 | Z |
| * | 1 | DataIn |
| * | Z | UX |
| * | W | UX |
| * | L | Z |
| * | H | DataIn |
| * | - | UX |
UX: if dataIn == U then U else X DataOut*: Strength map for DataOut according to tristate table Buf3sTable