;If you were overdriving the device, you would notice erratic
;operation long before it "blew up". The usual symptom of an
;overdriven crystal is jumping to overtone and spurious modes so it
;appears to run fast. This might be a few percent (spurious) or three
;times the rated frequency (overtone) although it can go quite high.
;You can get a few MHz out of a 32kHz crystal if you hit it hard
;enough.


I had some Z80 boxes that liked to run on the 5th overtone. Get a
scope on the line and increase the resistance until the crystal gets
slow starting and back off about 50 to 75% on the resistance.

Gordon

Gordon Couger gcouger@rfdata.net
624 Cheyenne
Stillwater, OK 74075
405 624-2855   GMT -6:00

Steve.
======================================================
Steve Baldwin                Electronic Product Design
TLA Microsystems Ltd         Microcontroller Specialists
PO Box 15-680, New Lynn      http://www.tla.co.nz
Auckland, New Zealand        ph  +64 9 820-2221
email: steveb@tla.co.nz      fax +64 9 820-1929
======================================================