Dimitris Kapousouz wrote : > Any info about the PIC16F88 ? The data sheet says "The OSCTUNE register has a tuning range of +- 12.5%.". What is unclear about that ? The 12F675 might be similar. I get the feeling that you'd liked to use the OSCCAL and OSCTUNE registers to force the PIC to run at another speed then the nominal. If so, why do you need that ? To sync to some other system ? Perhaps there are better ways to do whatever you need to do. It would be interesting to know why the min/max range is important. Best Regards Jan-Erik. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body