connection:
Just connect 6 lines between the MAX31865 module and the EXP1 connector, and remove one resistor then solder 1 line to the pandapi board which is the control signal line of mosfet for the hotend0.also remember to unplug the old temperature sensor on the T0 connector.
2.enable the max31856 in configuration.h
#define MAX31856_PANDAPI if you want to use other GPIO for the max31856,you can edit the pins in file pins_PANDA_PI.h.
test video:https://youtu.be/LhGSKaXKsbw
note: please keep one eye on the hotend before you have test it ok and stable.