Using MAX31865 module on Octopus 1.1

General Discussion
1

I’m trying to connect the PT1000 thermistor of my Rapido to my Octopus 1.1 board, but can’t get it to work. Keep getting error 'Thermocouple reader fault'

I have the BTT MAX31865 module installed in the DRIVER4 slot and configured the slot for SPI (all jumpers installed on black for that port). The thermistor is connected to the middle two pins for that driver. Jumpers on the modules itself are set to ON-ON-OFF-ON

I use the following extruder config:

sensor_type: MAX31865
sensor_pin: PF2
spi_software_sclk_pin: PA5
spi_software_mosi_pin: PA7
spi_software_miso_pin: PA6
rtd_nominal_r: 1000
rtd_num_of_wires: 2
rtd_reference_r: 4300

Does anyone have a clue why this isn’t working? The logs shows conflicting information regarding the MAX31865, doesn’t make sense to me…

Max31865 RTD input is disconnected
Max31865 RTD input is shorted
Max31865 VREF- is greater than 0.85 * VBIAS, FORCE- open
Max31865 VREF- is less than 0.85 * VBIAS, FORCE- open
Max31865 VRTD- is less than 0.85 * VBIAS, FORCE- open
Max31865 Overvoltage or undervoltage fault
MCU 'mcu' shutdown: Thermocouple reader fault

What am I missing here?

klippy.log (108.7 KB)

2

Make sure you have the jumpers set correctly for the PT1000 you are trying to use.

OR

You might have more luck connecting it to SPI3 connector just below the ARM processor.

3

Jumpers are set to the specifications in the manual.

Don’t think I can use another port, as it’s designed to be connected to the stepper driver output port as I have now.

4

While the driver ports are SPI1, you can wire it to be an off-board device to the unused SPI3.

5

How should this be configured and connected?

6

Fixed it. Stupid mistake, had all the jumpers of the driver port (to put it in SPI mode) reversed…

Apparently this causes these conflicting errors in the log. Hopefully if anyone else will ever encounter this, this post can help solve their issue :wink:

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