Frequently when doing simulation of a design I'll change time
constants so I can run the simulation in a reasonable timescale.

I like to keep things simple so to date this has mostly involved
commenting out the 'proper' value with a -- XXXX comment at the end
of the line. When I want to do a real workd build a search for
-- XXXX throughout the design should allow me to quickly find the
values that need changed and comment them back to their correct
values.

Except I keep forgetting. Over the years this has caused hours of
lost work until I have realised what I've done.

I've thought of including a generic in all my modules by default to
indicate whether simulation or real world build is being done, this
could be propogated down from the top of a design to select which
values are being used. Another solution would be a script to search the
source directory commenting out --XXXX lines and uncommenting -- YYYY
lines (for example).

But why re-invent the wheel....

Does anyone have a clever (simple) structured way of ensuring that
temporary simulation values aren't included when doing real world builds?


Thanks for any pointers,


Nial.