>A while back (before the N-bomb stuff, but maybe after the cow stuff)
>someone mentioned a problem with BURNING-OUT crystals by using the wrong
>value resistors.  I'm using 3.58Mhz ceramic oscillators with 56pf caps on
>a batch of 16C554's running at 3.3V from Ni-Cd batteries and NO
>resistors. Could this cause premature failures?  The 16C554 data sheet
>diagram and spec's don't include any limiting resistors for the
>oscillator circuit. The chips are programmed as having "XT" oscillators.

I burnt out a few 32Khz crystals using the PIC before I realized that I
needed a series resistor of about 10K or more. I think only the low
frequency crystals are more prone to burning out.