This is a known problem with MPLAB. I don't know exactly what causes it,
but if you move your mouse around, it will speed up the simulation.
There is a utility that speeds up your simulations, it has been
discussed on the list a few times. I lost the link for it though. I'd
have a look at the archives to see if you can locate it.

Josh

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"Michael A. Powers" wrote:
> It seems that simulations in MPLAB are very slow, I tried to simulate a > 24 bit counting program, and it takes forever to run.  I looked at the > CPU usage, and during a run MPLAB is using an average of about 1%, with > the remainder spent in idle.  Is this supposed to happen? Is there any > way I can speed it up?

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