Re-ARM for RAMPS

Hi, I’m new to Smoothieware. At the moment I’m remaking my Prusa I3 into a HyperCube CoreXY. in the process I’ll be upgrading my Arduino based electronics to Re-ARM for RAMPS. My E3D hot end is fitted with a PT100 and amplifier and I have a question about the configuration for PT100.

temperature_control.hotend.thermistor_pin 0.23
temperature_control.hotend.pt100linear    0            # use 0 for RDT curve (alpha/beta values)
temperature_control.hotend.pt100_a        0.0039083    # PT100 ALPHA value
temperature_control.hotend.pt100_b        0.0000005775 # PT100 BETA value
temperature_control.hotend.pt100_r0       100          # resistance at 0C
temperature_control.hotend.pt100_amptype  0            # type of RTD amp, attm only 0 supported (0 is e3d pt100 amp)

coefficients for the ADC to Rt formula

q1 * ADC_VALUE / ( Q2 - Q3 * ADC_VALUE)

temperature_control.hotend.pt100_q1 810000
temperature_control.hotend.pt100_q2 45409000
temperature_control.hotend.pt100_q3 280

coefficients that are also known to work with E3D amp:

#temperature_control.hotend.pt100_q1 11000000
#temperature_control.hotend.pt100_q2 606888919
#temperature_control.hotend.pt100_q3 2500

Does this config take into account any pullup attached to the thermistor pin? Or would it be better to use the RAMPS pin A3 which equates to P0.27 on the Re-ARM? RAMPS pin A3 is the pin I currently use. I have no problem with changing the pin but I’d rather not have to undo my wiring loom.

Imported from wikidot

PT100 is still a beta feature, it’s only been added recently, and I’m not 100% sure if the code is in the main firmware yet or if it’s still waiting for further testing.

Has the PT100 code been incorporated into the latest Edge build?

No, it’s here : https://github.com/Smoothieware/Smoothieware/pull/1086 and is waiting for some users to test it before merging it.

Hi TGMods,

I am looking into getting a PT-100 for my Ramps RE-ARM. Have you had any luck getting it setup? I haven’t been able to find a lot of good information on it.

Any info is appreciated.