--- Quote Start ---
What is the constant doing? If the constant is a generic used on components within the design, then you can just set the generic in Quartus via a Tcl synthesis script or via the GUI. If however, you have a 'generic package', then it depends on the support for that feature in Quartus ... last time I looked that construct was not supported, but I haven't tried in 11.1sp1.
--- Quote End ---
I should have chosen the following example:
package simulation_pkg is
-- if this constant is set to true some settings which have a strong
-- impact on simulation time are set so that the simulation runs faster
constant simulation : boolean := true;
end package simulation_pkg;
This setting influences the values of some counters and the bitwidths of some signals in my component. When this setting is set to true some initialization counters will count for only a few cycles instead of a few thousand cycles. This way the simulation time is drastically shortened. The synthesis will fail because if this value is set to true then the toplevel file expects some signals, which the component exposes, to have other bitwidths (luckily for me the synthesis fails in this case, it would be worse if synthesis was successful and I didn't recognize that I synthesized the system with the wrong settings...).
Regards
Martin
Honored Contributor
