Hi Rickard (Rickard Gunie), in <34B25EA1.3503E436@efd.lth.se> on Jan 6 you
 wrote:

> How fast can a PIC16C84 run ? I would like to run it @ 12MHz, have
> anyone tried this ? I have done it with one chip, it broke after a
> couple times of reprogramming. Is it possible to determine if the chip
> can run @ 12Mhz without breaking it ?

Buy the 10 MHz Version. It will probably run 12 MHz without too much
trouble.