I've used the OSC2/CLKOUT to drive two loads a 16C750 and a 16C552. No
problems.

Cypress has some nice clock products (probably to much money for this
project).

Todd Conard

Bob Drzyzgula wrote:

> On Fri, Aug 27, 1999 at 07:27:43PM -0700, Anne Ogborn wrote:
> >
> > How do I tie pin 1 to the crystal?  Just tie it to OSC1 or OSC2?
>
> I think that, on the PIC, OSC1 is nominally the input,
> while OSC2 is nominally the output. However, I don't think
> (watch everyone else say different) that it's recommended
> that you use those as a clock source for other chips if
> you're using the built-in oscillator with an external
> crystal; I'm not sure that the PIC's oscillator has
> sufficient drive for that (I know that it's been discussed
> before, but it may come down to one of those questions
> where the answer depends on how much of a problem it
> would be for you if it didn't...)  If you forgo the PIC's
> oscillator and make your own (mostly you need some more
> resistors and an inverting buffer like the 74x04), then
> the inverting buffer will have plenty of oomph to drive
> both the PIC and other devices. uChip shows how to do this
> in most data sheets, e.g. Figure 13-6 in the PIC16C6X
> sheet. Where it says "To Other Devices", that's where
> you'd pick up the signal to feed the 4024. Alternatively,
> I suppose you could simply feed the 74x04 output straight
> into the 4024, drive the PIC off pin 12 of the 4024 and the
> ISD off pin 11.
>
> BTW, the 4024 is also available in HCT; uChip shows
> using an AS device feeding CLKIN... does it matter
> if the CLKIN is fed CMOS or TTL levels?
>
> --Bob
>
> --
> ============================================================
> Bob Drzyzgula                             It's not a problem
> bob@drzyzgula.org                until something bad happens
> ============================================================