Does this also cover the thermistor on the heated build platform?
Adjusting The Thermistor Settings / Discussion
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This is the discussion related to the wiki page Adjusting The Thermistor Settings.
Right now, there is only one thermistor lookup table. It's unlikely I'll hack this much further until the v2 firmware is out.
I'm using the same model thermistor and same resistance value (I hope) on my heated platform as what is published as being used on the nozzle…so I hope the same table would work. So, does this version support two (hopefully nearly identical) thermistors for the nozzle and heated platform…. I guess I'll have to download it and try.
It appears from a bit of experimentation that the firmware is reading A0 instead of A6 for the platform thermistor…oops! What do I have to change to fix this?
The heated build platform support is actually turned off in this build of the firmware (it's considered experimental…) You can rebuild the extruder firmware from source. Just make sure to edit the Configuration.h file and set "HAS_HEATED_BUILD_PLATFORM" to "1".
In step 6 of the two-pass calibration method, it says to "Measure the 5VDC (H) supply across the regular IC terminals"… Can this be clarified please? Which terminals of which IC will show the voltage for H?
Thanks for catching that. I meant to write "regulator IC". I've fixed it and added some clarification.
Thanks, that is much clearer now, except for one thing: correct me if I'm wrong, but the two legs of the 7805 are the input and output voltages (12v and 5v, respectively), so the voltage across those terminals should be 7v (input voltage minus output voltage), and is not the voltage we are looking for, is it? Shouldn't we be checking the voltage across the output pin of the 7805 and ground? I only figured this out because I checked the voltage across those leads on my Makerbot that I am currently calibrating, and got the rather confusing result of 7.2v, and it took me a bit to realize why. :)
Unfold
Re: Need clarification - two-pass calibration method steps by 
Littlebear42, 07 Jul 2010 16:48
This is one of those places where an annotated picture would probably help more, but yes you want to measure the voltage between the 5VDC output terminal (small leg on the right) and ground (wide terminal along the top edge).
I'm having some trouble getting the current temp and target temp matching up. I've tried the posted values with no success. It hold temperature very nicely but ~6 degrees below the target (ie. holding at 214C when I want it at 220C). The thermistor looks flush against the nozzle but it is sticking out a bit from the insulation. Any suggestions would be great.
Thanks.
Oh wait. I got it.
/forum/t-214632/adjusting-the-thermistor-settings#post-
