One of the main problems (probably listed in that link, I haven't looked) is that some of the clone devices all have the same serial number. Proper DS18B20s are supposed to have unique serial numbers burnt into each chip. Without unique serial numbers you can't tell the sensors apart, so can't have more than one connected to the same gpio pin.The knockoffs are a problem because they are a lot less accurate (+/- 2°C vs +/- 0.5°C) and lack functionality plus bring other problems, see the link above. Though that missing functionality might not be relevant in a lot of situations the inaccuracy alone can be trouble.
You can, of course, use more than one gpio pin for the sensors, or if you're only using one sensor per device it isn't a problem.
I've been lucky so far and all my DS18B20s have different serial numbers, although the accuracy of some of them is rather questionable.
Statistics: Posted by rpdom — Fri Mar 14, 2025 9:27 am