Re: 1-Wire Headache

[Stuart Poulton <stuart.poulton@xxxxxxxxxxxxxx>]

Marc,

85c is the reading that is returned as an error, normally that a
conversion wasn't able to be made.

2 questions

1 - Are you making connections to all 3 legs of the sensors ?
2 - What sort of cabling are you using.

I've successfully run 1-wire over 100m of cat5, using modules that
daisy chained (modules of my own design)

Cheers

Stuart

On 17 Jul 2007, at 17:49, Marc Fuller wrote:

> Hey Guys,
>
> Just bought myself a TEMP08 to replace my Quasar logger. It's all
> up and
> running and 3 of the sensors are working perfectly. My problem is with
> the fourth.
>
> For some reason the fourth sensor that is at the end of the bus, keeps
> showing a temperature of 85c, which is obviously not correct.
> Occasionally it will show the correct temperature, but mostly it shows
> 85c. I replaced the probe with a new one and am getting the same
> thing !
>
> Now I must admit I don't totally understand 1-wire yet.. this is my
> first proper jump into it. So it could be that I have set up the bus
> incorrectly ? or what else is likely to cause this problem ?
>
> The probes are wired in series and the farthest one is only about 10
> meters away.
>
> Anyone got any ideas ? Could I just be really unlucky and have two
> probes shorting out ?
>
> Any help appreciated
>
> Marc
>
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