Davinci 1.0 E3d V6 conversion and temperature values

Hey.

Congrats on the upgrade, better late than never!

Yeah, as you already know the Davinci's board is pretty unique and a bit of a headache to modify for the E3D.

So, there's two ways to make this work, and which way depends on what exact Davinci model motherboard you're running.

Both answers do require you to modify a firmware configuration file, compile the firmware, and flash it to the printer manually using the Arduino software. See these instructions here on how to do that.

Now, are you running with a first generation 1.0 motherboard? Or a 1.0a motherboard? (Even if your Davinci isn't labeled a 1.0a, they did motherboard revisions in-between, so check)

How to check:

Does your motherboard have these ugly little stepper driver chips on it?
If yes, then it's a first generation (1.0) motherboard, and it'll be a bit more complicated to work with.

Two main steps:
1. In this case, yes you do need to remove the R29 SMD resistor (1k Ohm resistor) from the motherboard first unfortunately.
2. After, you'll need to modify the configuration.h file included with firmware you downloaded from that github link above.

• Scroll down the file and look for #define EXT0_TEMPSENSOR_TYPE 5

• Change the type to 8 (which is meant for E3D's Semitec 104GT-2 )

• Compile it and upload it to your printer just the same way you did it the first time etc etc.

(Sidenote: By removing this resistor you can now use any of the standard tables in the future for different thermistors)

If your board doesn't have the ugly little drivers or it's blue, then it's a second generation (1.0a) motherboard.
You're in luck, because someone already generated a custom table specifically for E3D's Semitec 104GT-2 and the Davinci (1.0a) board resistors!

All you'd need to do in this case is software based:
1. Modify repetier's configuration.h file:

• Scroll down the file and look for #define EXT0_TEMPSENSOR_TYPE 5

• Change the type to 7 (which is meant for the custom table designed for the Semitec and the Davinci)

• Compile it and upload it to your printer.

I really hope this helps! It's a bit of a mess with all the different board revisions and Davinci models.

Voltivo's forums closing also made things worse since there was a bunch of useful information hosted there. Looks like Google's cached feature doesn't work on those old forum links either.
I remember years ago it being relatively active. Sad that it's gone now.

Anyways, good luck and tell us how it goes!

Oof, hope I'm not too late. I can't remember the exact circuit right at this moment but don't jump/bridge that resistor!

I think it was a either a pull up or pull down, but either way it may or may not cause a short and destroy a pin on the processor.

I found this blog of someone upgrading their 1.0 to an e3d as well that might help you too. He removes his R29 and leaves it empty.

And yep, the new cartridge thermistor is the same as the older one just in a better format.

I'll try to double check on one of my spare 1.0 motherboards and see how it was set up tomorrow when I get a chance!

Just to be safe instead of bridging should you decide to, you can replace it with a zero ohm resistor and in the event there is a problem the resistor should open like a fuse before any real damage occurs.

Hey!
Had a busy day and didn't get around to posting earlier.

Anyway, after checking out the circuit in person, it's schematic looks like this voltage divider setup:

3V3 ---
          |
          |
     4.7K (R27)
          |
          |
          ------------------------------------------------------> (MICROCONTROLLER THERMISTOR INPUT) (PB20, Pin 91)
          |                            |                           |
          |                            |                           |
(THERMISTOR)           1.0K (R29)                (C29)
          |                            |                           |
          |                            |                           |
GND ------------------------------------------------

Bridging R29 will just short 3V3 to ground and show 0V at the MCU's input, stopping from the thermistor from working at all.
(It won't be destructive as I feared though, since R27 is already in series with 3V3)
Removing it will just leave a typical voltage divider circuit.

The purpose of that specific resistor was to reduce a bit of power dissipation (thermistors self-heat a small amount when powered) in whatever XYZ's thermistor originally was for more accurate readings. It's explained here near the bottom of the post.
Most reprap machines don't bother with that extra resistor, which is why these tables don't work.

Also, the motherboard used in SD Perry's blog post from earlier is definitely a 1.0-older revision board. He might be confused, or alternatively for some bizarre reason has an older motherboard on a 1.0A. Good catch though, didn't notice that small bit in his title somehow, lol.

Hope this helps!

Awesome man, glad to hear back that it's working well for you now!

Wish you luck with your future prints and enjoy your e3d!

Unless it has been damaged just the the thermistor in the original hotend in the E3D. Otherwise R29 does have to be removed. It can be done with a hotair gun and a very small nozzle. Or you can make a solder blob on one side that will heat both ends and then remove it the resistor with tweezers and clean the solder up with some solder wick.

So the original thermistor has been damaged? It would be much easier to use it.