|
The following predefined evaluated functions are built into AHDL; that is, no Define Statements are needed to use them:
The USED
function can be used to test whether a port has been used, for example, in an If Generate Statement or a Parameters Statement. USED
takes the port name as input and returns a value of FALSE
if the port is not used.
The CEIL
function specifies the ceiling of a real number, which is the smallest integer
that is equal to or greater than the real number. Although this operation applies to all
arithmetic expressions, it is meaningful only for LOG2
and DIV
operations
in which the result can be a real number.
FLOOR
function specifies the floor of a real number, which is the largest integer that is equal to or less than the real number. Although this operation applies to all arithmetic expressions,
it is meaningful only for LOG2
and DIV
operations in which the result can
be a real number.
You can use these predefined evaluated functions in arithmetic expressions only; you cannot use evaluated functions in Boolean expressions.
- PLDWorld - |
|
Created by chm2web html help conversion utility. |