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harryweb
- 26th November 2013, 16:45
Hi,

As I have some problems using multiple 16MHz crystal (and PLLx4 enabled) on 5 pics,

I plan to use 1 x external crystal oscillator @ 64MHz with multiple pics (without PLL) in //

Where can I find connection examples ? (using buffers ?) Is there any problem to do it ?
Do you know some oscillators references that are the most easy to connect ? (digikey/mouser...)

Regards

rsocor01
- 26th November 2013, 21:31
Hi,

As I have some problems using multiple 16MHz crystal (and PLLx4 enabled) on 5 pics,

What problems are you having? Post your code with your config settings. It is not that hard to make the PLLx4 to work.

Robert

Amoque
- 26th November 2013, 21:55
You might also look at some previous posts on the subject as here: http://www.picbasic.co.uk/forum/showthread.php?t=575

Charlie
- 27th November 2013, 13:53
Choose an oscillator module rather than a crystal. They are capable of driving multiple loads without buffering. 5 is getting near the limit, but should be fine.

Acetronics2
- 27th November 2013, 14:05
You can find your answer in the Microchip midrange manual ...
DS31002A-page 2-11

and also probably in the relevant Pic datasheets ... oscillator section.

also add interesting readings ...

• AN826, “Crystal Oscillator Basics and Crystal Selection for rfPIC® and PIC® Devices” (DS00826)

• AN849, “Basic PIC® Oscillator Design”(DS00849)

• AN943, “Practical PIC® Oscillator Analysis and Design” (DS00943)

• AN949, “Making Your Oscillator Work” (DS00949)

Alain