> Bob Barr wrote: > > > > Roman Black wrote: > > > > > > > > > >What is your main problem? Disabling the wdt is > > >probably making the PIC do more instructions per > > >second which will use more power... > > > > > > > How would having the WDT disabled allow more instructions per second to > > execute? > > > > Is there some aspect of WDT operation that I've missed? I can't see any way > > that disabling the WDT could alter the processor's execution rate. (A big > > "DUH" in advance if I am overlooking something obvious.) > > > You are totally right Bob. > I had one of those "brain burps"... :o) > > For some reason I thought he was talking about > disabling sleep mode... Sorry about that! > > As a lame attempt to save myself, I could suggest > that as the WDT is a RC osc inside the PIC, it > would be possible for the PIC to use more power > with the WDT disabled IF it disables with the > cap in the discharged state. It must disable in > one state or the other, if it disables with the > cap held high it will use less power than when > running, cap held low uses more power than running. > > I know they made quite a few hardware changes from > the 16c84 to the 16f84, many focused on reducing > power drain. That might be one of them. > -Roman Thanks guys, The 16C84 I have must be a weird one. I will get my hands on a 16F84A and give that a whirl. From past experience with a 16C63 the watchdog timer added something like 20uA (I dont recall the precise value, but I'm sure it's in a data sheet). Brent Brown Electronic Design Solutions 16 English Street Hamilton, New Zealand Ph/fax: +64 7 849 0069 Mobile/text: 025 334 069 eMail: brent.brown@clear.net.nz -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.