Quote Originally Posted by Bruce View Post
Charles,


Were you testing this by boot-loading with the internal osc and a serial loader, or just testing to see if the PIC failed at these temps?

If so - which PIC were you using? I've had problems in Colorado when the temperature fell below freezing with serial loaders using the internal osc. And more when the board was in an enclosure exposed to direct sun.

Just curious. That's pretty good if you were boot-loading with a serial loader using the internal osc at these temperatures.
We were not actually boot-loading at those temps. We were, however, continuously doing serial I/O at 19,200 baud. No problems. Note that we were using 18LF2321's at 5V.
Many years ago, I found that some other chips (in the 16F series) were not nearly so accurate - or stable.