Ok so I had 6 DS1820 temp sensors setup on my Arduino monitored throught Hubduino, all is good. I decide to add 4 new sensors, no problem right? Well, not quite. All my assignments for tiles were messed up. I am thinking that the issue is that the serial numbering of the sensors are assigned in some sort of logical way to temp sensor1, temp sensor2, etc. And when there are new sensors introduced that gets rearranged. So my question is: Is there a way for me to complie a list of which one is assigned where? That way later if I add more sensors I will have an easier time of getting things back where they belong?
Unfortunately, I don’t have a simple way of doing that. I chose simplicity in the design to support multiple DS18B20 temperature sensors on a single pin. As long as the sensors don’t change, the order seemed to be consistent in my testing. Adding or removing sensors, results in the list changing.
If you’ve got the pins to spare, you can attach each DS18B20 to a unique pin to guarantee the behavior never changes.
Yeah I figured, we might have had this conversation earlier when I was using ST. I would have to see if I have enough pins, not sure. Is it the sketch change that triggers the reorder? I could set it up for more than I could imagine, and if adding one just put it to the end of the existing I can live with that.
Thanks
Nothing you can do in the sketch. The sketch’s number of temperature sensors needs to match what is connected. I’m not sure what would happen if you defined more sensors than are actually connected.
Didn't think so. I did have more in the sketch than connected up initially. I think I had 6 enabled and 4 connected. The extra two showed up as -196.96 and the others worked fine. So either we learned something about how the sketch the number of devices that are actually connected OR I got lucky and it worked out... 
To identify individual devices, you can put them into either a hot or cold pack (depending on whether it is inside or out) and then check them one at a time for a temperature change in the interface.
Yup done that before. Or as Dan suggested to divide them up to individual pins. I am thinking about something like that.
There is some wire length and voltage dropoff that happens with these devices. I have some where I have very long cables. Total cable length is maybe 80 feet. With three on one string, everything works fine. If I add one more, even on a short cable, I either get nothing or mostly nothing. Just adding this for fun.
Yeah I have a couple of runs that might be that long with two or three sensors on it. that's for the pool water tho, won't need that for a couple of months LOL. Most of my runs are about 30 feet long. I have been using Cat5 cabling for all of them too.
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