More temp probes

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ScottT
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More temp probes

Post by ScottT »

Is it possible to have more than 3 temperature probes on a Reef Angel?
rimai
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Joined: Fri Mar 18, 2011 6:47 pm

Re: More temp probes

Post by rimai »

Yes, but the controller only has 3 ports.
You would need to splice an extension to have more ports.
The other thing that would need to be done is libraries changes. It's hard coded to only 3 probes right now.
Roberto.
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ScottT
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Re: More temp probes

Post by ScottT »

Thank you,
I'm not up for that quite yet, but maybe one day. Three will do for now :-)
Piper
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Re: More temp probes

Post by Piper »

Roberto - Is there a limit on the probes if you splice like that?
rimai
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Re: More temp probes

Post by rimai »

I think just RAM memory constrains.
You will probably start seeing errors when the capacitance hits a certain level.
More cable = more capacitance and the pull-up resistor can't keep up to pull the data line as fast as the signal needs to be, which will cause errors.
At this point, I'm sure there are dedicated chips to pull-up the data line faster than a single resistor.
Roberto.
Piper
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Re: More temp probes

Post by Piper »

I'm still on chapter 1 in my Electronics for Dummies book so maybe I need to rephrase my question :) I can probably get away with 5 total if I wanted to, yes?
rimai
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Re: More temp probes

Post by rimai »

You should be fine with 5
Roberto.
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