How to wire up the SKR E3 V1.2

On this board you'll need to wire up the +5V from a step-down converter, such as the LM2596 or the specific Bigtreetech DCDC 5V add-on module (see notice down below).

The PT-DET header is used to drive Servo1 (either Wiper servo or Cutter servo - you can't have both because there are not enough I/O pins available). However, keep in mind that the wiring is different on this header! Instead of SIG, +5V, GND (which is a common configuration for servos) on this header it's +5V, GND, SIG. Before you connect a servo to it, make sure you've swapped the +5V and the GND wire.

Keep in mind that this controller has the TMC2209 drivers soldered directly onto the board. Hence, the initialization of these drivers is different. All configurations, such as Vref and Microstepping, etc. are done by software. So, in order to initialize those values correctly, you have to - at least - set Mode to UART in the TMC settings for each stepper driver used.

For wiring up the display, please refer to the Using other Displays page.

Ressources:

Pin diagram Schematics