If you are implementing the simple multiplier mode and using the
LPM_MULT function, you can set the
LPM_PIPELINE parameter to 1, 2, or 3. When set to 1, it uses the input registers. When set to 2, it uses the pipeline registers. When set to 3, it
uses all 3 input, pipeline, and output registers.
For the other modes, the
ALTMULT_ACCUM functions have these registers specified explicitly in the MegaWizard® Plug-In Manager.
If you want to use just the input and output registers (bypass the pipeline registers) in the simple multiplier mode, you can use the
ALTMULT_ADD function, implement an independent multiplier by setting the
parameter to 1, and then explicitly specifying the appropriate register stages.