The Logic Section specifies the logical operations of the
Text Design File
(.tdf). This section is required. One or more of
the following statements or constructs may be used in this
section:
- Boolean
Equations
- Boolean
Control Equations
- Case
Statement
- Defaults
Statement
- If Then
Statement
- If Generate
Statement
- For Generate
Statement
- Assert
Statement
- Truth Table
Statement
Note: The Logic Section can also include Assert Statements.
The BEGIN and END keywords enclose the
Logic Section. A semicolon (;) follows the
END keyword and terminates this section. The Defaults
Statement must be the first statement in the section.
Note: AHDL is a concurrent language. The Compiler evaluates all behavior specified in the
Logic Section of a TDF at the same time rather than sequentially. Equations that assign
multiple values to the same AHDL node of type NODE or variable are
logically ORed or ANDed. Refer to Boolean Equation Rules or Defaults Statement Rules for
more information.