On Tue, 4 Jan 2000, James Paul wrote:
>  Regarding the 4 lead crystals.  Are these actually crystals or
>  are they canned oscillators?  Do they look like a DIP package
>  with 1 pin in each corner?  And all corners are rounded except
>  one which indicates pin 1?

That is it.

>  If this in fact is what you have,
>  then pin 1 can be either N/C or a TRISTATE pin, Pin 7 is GND,
>  Pin 8 is OUTPUT, and Pin 14 is Vcc.   If you have the halfsize
>  parts then Pin 1 is either N/C or TRISTATE. Pin 4 is GND, Pin 5
>  is OUTPUT and Pin 8 is Vcc.  These are easy to see if they
>  operate.  Just provide power to pin 8 or 14, Ground pin 4 or 7,
>  and measure pin 5 or 8 with a scope of frequency counter.  If
>  you don't see any activity, then pull pin 1 high in either case
>  to enable the TRISTATE output.

*tinker*  Ahh, I got my PIC running with a ferw of them at different
speeds.  I was never able to get it to work before, thanks!  I had
assumed that you needed to take two of those pins into the CLK1
and CLK2 like a 2-pin crystal, but I see that was incorrect now.

So the 4-pin units have a crystal and an oscillator.  I assume the PIC
has to have an internal oscillator since it can run a regular 2-pin
crystal?

Is a resonator equal (with less accuracy) to a 2 or 4 pin osc?

>  If you could supply some of the numbers on the top of the 4 pin
>  crystals, that may help identify them easier.

CTS SINGAPORE; MXO-55GB-2C; 1.8432 MHZ; 8747 1202
CTS KNIGHTS INC; MXO 50-2; 19.584 MHZ; 8138 028
6N/S TD1145C; 25.175MHz; 8918 NDK JAPAN
CK1145MC; 28.322200MHz; 8912

Do the 8xxx numbers refer to some common standard?  They all seem to
have them, even though they are made by different companies.

--
IanSmith@erie.net