Web, Sorry for confusing question. My question is in general: on pic project pic18f4550 I am using external oscillator and configuration setting is EC and I did a test to change it to HS then it worked and I forgot to change it back to EC but the project is working and I am worried about it to understand the difference between the EC and HS. Now let me answer to my own question: The only different between EC and HS is if osc out pin is used as I/O EC must be set then internally OSC out pin will be disconnected and be ready to use as I/O but when HS is used OSC in and out pins are used OSC out pin as I/O can't be used and it will simply oscillate. In my case I do not use OSC out pin as I/O so I do not need to worry about it. thank you Andre -----Original Message----- From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu]On Behalf Of M Wedin Sent: Friday, February 29, 2008 1:38 AM To: Microcontroller discussion list - Public. Subject: Re: [PIC] Clock setting HSPLL vs ECPLL What's wrong with asking why it works? Could be good to know when it no longer works. And if it's the "proper" way to go. Wed 2008/2/29, Rikard Bosnjakovic : > > On 28/02/2008, Andre Abelian wrote: > > > I used HSPLL instead of ECPLL to program some boards that it is too > late > > to open them. HS is for crystal and EC is for external clock. HS works > for both. > > Does any one know why HSPLL works for both and it is safe to use it. > > > What boards? > > And I'm a bit confused. If HS works for both, why asking why it works > for both? Are you talking about PIC-chips or complete set of > demo-boards? Or, what are you really asking? We have no clue. > > > > -- > - Rikard - http://bos.hack.org/cv/ > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist