On Nov 18, 2007 7:37 AM, Xiaofan Chen wrote: > On Nov 17, 2007 2:54 AM, wouter van ooijen wrote: > > > I use pic18f4550 and I noticed that the pic looses it's > > > program memory I am not sure how many % but it is enough to > > > see things are not working and this is my 3rd time I started > > > doing hardware trouble shooting and I ended up reprogramming > > > pic fixed the problem. The only possibility is the part got > > > over heated while soldering. any idea? > > > > Got the same problem, with 18F2550's (a pickit2 clone circuit). My > > current guess is that I have open inputs. I will add a few more > > resistors to the next batch, but that is due only 2008Q2. > > > > More likely it is due to the power supply and the fact > that brown-our reset is disabled in PICkit 2 firmware (Walter > mentioned it is because Brown out reset interferes with > some normal operations). It may also have something > to do with bootloader. > > IMHO other vendors like Silabs (C8051F) and Atmel (AVR) have > more problems. Example: > http://www.cygnal.org/ubb/Forum1/HTML/002399.html > It is the same for Atmel 8051 and we always use an external reset circuit with AT89C51CC01. http://www.atmel.com/dyn/resources/prod_documents/doc4183.pdf Xiaofan -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist