To get a period of 250 out of TMR2 you set the PR2 register to 249! Bob Ammerman RAm Systems ----- Original Message ----- From: "Andrew Warren" To: Sent: Tuesday, November 26, 2002 2:57 PM Subject: Re: [PIC]: Clock accuracy > Tauno Siitam wrote: > > > I initialized TMR2 with prescaler 4, postscaler 1:1 and period 250. > > .... > > clock lags behind about a second in 4 minutes. IMHO, the error is > > too big to fix it only in software. So there must be something else > > wrong. > > Your humble opinion is almost certainly wrong. > > "About a second in 4 minutes" is the same as 1 in 250. 250 is > your period, so your software is probably off by one somewhere. > > -Andy > > === Andrew Warren -- aiw@cypress.com > === Principal Design Engineer > === Cypress Semiconductor Corporation > === > === Opinions expressed above do not > === necessarily represent those of > === Cypress Semiconductor Corporation > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body