Feature request: support for DS1820 temperature sensor?

[jeremie 13]

Could Marlin and marlin autobuild support the cheap one-wire digital dallas DS1820 (or DS18B20) temperature sensor?

I used one on my heated bed controlled by a separate arduino pro mini because it is plain straightforward (no conversion nor lookup tables needed). Now that I know it's OK I would gladly control it from within a "regular" Marlin instead.

[codemaven 0]

The problem with the DS1820 is that it's range is only good up to 125 degrees C. That's not high enough for a hot-end and barely high enough fro a heated bed... And I wouldn't trust the plastic package for either scenario... I think even for a heated bed, if you want to do ABS or some more exotic materials you're going to really push the limits of the chip and if it fails or mis-reports you could have a fire-hazard. I would want much more head-room on the hot side myself.

Cheers,

Troy.

[jeremie 13]

Oh, that's true

It's still OK for my heated bed (PLA only and low temp), but I definitely should have read the specs twice.

Not worth it, ignore my request

Thanks

[phut 0]

I think the ability to enter in your own custom temp sensor tables would still be very useful in the marlin builder though.

As for thermal sensor reliability, even if we discount the chance of the temperature sensor failing (or use a 'fail safe' sensor) there is still the issue that the Arduino isn't a safety device and could be liable to control failure (and the issue with the boot-loader not allowing the watchdog to fire in the case of failure etc.). If you're really concerned about overheating or whatnot you ought to employ a last line of defence, which would probably best be a thermal fuse.