SOFT buffer specifies that a logic cell may be
needed in the project. During project processing, Analysis &
Synthesis examines the logic feeding the primitive and determines
whether a logic cell is needed. If it is needed, the
SOFT buffer is converted into an
LCELL; if not, the
SOFT buffer is removed.
If the Compiler indicates that the project is too complex, you
can edit the project by inserting
SOFT buffers to
prevent logic expansion. For example, you can add a
SOFT buffer at the combinational output of a logic
function to decouple two combinational circuits.
- When you turn on the Ignore SOFT
Buffers logic option, the Compiler automatically
WIREprimitives. For newer device families, the Ignore SOFT Buffers logic option is turned on by default.
- For information about Quartus® Prime primitive instantiation, go to Using a Quartus® Prime Logic Function.
SOFTprimitive is not recommended for newer device families.