I'd been running 6 DS18B20's for 2 years reading temps in a saltwater tank and ambient air as well. Originally they were running parasitic, but later set them up powered individually. A couple months ago 1 of them died and started reading -196*F, but I already had redundancy so I hadn't replaced it yet. Today all of the temps read 32*F (0*C). In the past, this has happens every couple of months, I simply reboot it and then it's fine. But today no amount of rebooting, wire jiggling, what-not will fix it. If I pull the "one wire" while it's running they all got to -196*F.
It's been 2 years since I touched the code, and I know all sorts of things have changed, but I have to assume it's a hardware issue. Anyone have thoughts as to what I can look for?