On 6/2/06, Barry Gershenfeld wrote: > There's a long-standing tradition of using a little three-terminal reset > generator to make sure the PIC starts up properly. I suspect there was > some trouble with this many years ago and we just kept up the > practice. So what I'm asking today is if we all trust the PIC internal > reset circuit to work reliably, every time. Expected answers will be > 'yes', 'no', and 'it depends'. So far I have only used 4 PICs (16C72A/16F872/16LF872/12F629) in 4 projects (somehow every project was longer than I expected...) and I only used a reset IC for the 16LF872 and it is because of the brown out reset does not work the way I like since I powered it using 3.3V and the brown out reset does not work at that voltage for 16LF872. The 16C72A design was released in year 2001 and now runs at more than 100k per year in the field in chemical, pharmaceutical and petrochemical industries. Startup in general is not a problem for PIC. For some other MCUs, we do put external reset circuit. Regards, Xiaofan -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist