The limit switch sensor inputs are delivered straight into the ST microcontroller without any protection or filtering.
Suggested Solution
At least add a low pass filter (RC with 1.5k resistor and 1uF capacitor) to the line from the input connector to the micro. This will provide a low pass filter with ~106Hz cutoff which is plenty for the limit switch. A TVS diode would probably also be a good addition.
This will also stop any interference from the cables of the steppers.
Version Number
All
Bugfix or Enhancement
Enhancement
Description
The limit switch sensor inputs are delivered straight into the ST microcontroller without any protection or filtering.
Suggested Solution
At least add a low pass filter (RC with 1.5k resistor and 1uF capacitor) to the line from the input connector to the micro. This will provide a low pass filter with ~106Hz cutoff which is plenty for the limit switch. A TVS diode would probably also be a good addition. This will also stop any interference from the cables of the steppers.