Yes, I realise that but what I want to do is put an external clock in, = not use a crystal - the diagram implies that something funny may be going on in the way the PLL = is fed.=20 On Thu, 13 Feb 2003 11:24:17 -0800, you wrote: >It's my understanding that the PLL has the effect of multiplying the >frequency of your external oscillator by 4. So, if you put a 10 MHz >crystal between OSC1 and 2 and activate the PLL, the chip will run at 40 >MHz. My PIC18's haven't arrived yet though, so I very well could be >wrong, but I think this is how it works. > >Daniel Imfeld > >----- Original Message ----- >From: "Mike Harrison" >To: >Sent: Thursday, February 13, 2003 11:00 AM >Subject: [pic]: Ext Osc + PLL on 18cxx2 ? > > >Looking at the 18Fxx2 datasheet, it says that the PLL can only be used >in HS crystal mode, but it's >not clear whether or not you can apply an external clock in HS mode and >use the PLL - anyone know if >this is possible ? > >-- >http://www.piclist.com hint: The PICList is archived three different >ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.