added individual pullup setting option to have finer control in case there is a special z-min sensor, for example

Marlin/Configuration.h

@@ -127,9 +127,28 @@
 //=============================Mechanical Settings===========================
 //===========================================================================
 
-// Endstop Settings
+// corse Endstop Settings
 #define ENDSTOPPULLUPS // Comment this out (using // at the start of the line) to disable the endstop pullup resistors
 
+#ifndef ENDSTOPPULLUPS
+  // fine Enstop settings: Individual Pullups. will be ignord if ENDSTOPPULLUPS is defined
+  #define ENDSTOPPULLUP_XMAX
+  #define ENDSTOPPULLUP_YMAX
+  #define ENDSTOPPULLUP_ZMAX
+  #define ENDSTOPPULLUP_XMIN
+  #define ENDSTOPPULLUP_YMIN
+  //#define ENDSTOPPULLUP_ZMIN
+#endif
+
+#ifdef ENDSTOPPULLUPS
+  #define ENDSTOPPULLUP_XMAX
+  #define ENDSTOPPULLUP_YMAX
+  #define ENDSTOPPULLUP_ZMAX
+  #define ENDSTOPPULLUP_XMIN
+  #define ENDSTOPPULLUP_YMIN
+  #define ENDSTOPPULLUP_ZMIN
+#endif
+
 // The pullups are needed if you directly connect a mechanical endswitch between the signal and ground pins.
 const bool X_ENDSTOPS_INVERTING = true; // set to true to invert the logic of the endstops. 
 const bool Y_ENDSTOPS_INVERTING = true; // set to true to invert the logic of the endstops. 

Marlin/stepper.cpp

@@ -659,51 +659,48 @@ void st_init()
   #endif
 
   //endstops and pullups
-  #ifdef ENDSTOPPULLUPS
+  
   #if X_MIN_PIN > -1
     SET_INPUT(X_MIN_PIN); 
+    #ifdef ENDSTOPPULLUP_XMIN
       WRITE(X_MIN_PIN,HIGH);
     #endif
-    #if X_MAX_PIN > -1
-      SET_INPUT(X_MAX_PIN); 
-      WRITE(X_MAX_PIN,HIGH);
   #endif
+      
   #if Y_MIN_PIN > -1
     SET_INPUT(Y_MIN_PIN); 
+    #ifdef ENDSTOPPULLUP_YMIN
       WRITE(Y_MIN_PIN,HIGH);
     #endif
-    #if Y_MAX_PIN > -1
-      SET_INPUT(Y_MAX_PIN); 
-      WRITE(Y_MAX_PIN,HIGH);
   #endif
+  
   #if Z_MIN_PIN > -1
     SET_INPUT(Z_MIN_PIN); 
+    #ifdef ENDSTOPPULLUP_ZMIN
       WRITE(Z_MIN_PIN,HIGH);
     #endif
-    #if Z_MAX_PIN > -1
-      SET_INPUT(Z_MAX_PIN); 
-      WRITE(Z_MAX_PIN,HIGH);
-    #endif
-  #else //ENDSTOPPULLUPS
-    #if X_MIN_PIN > -1
-      SET_INPUT(X_MIN_PIN); 
   #endif
+      
   #if X_MAX_PIN > -1
     SET_INPUT(X_MAX_PIN); 
+    #ifdef ENDSTOPPULLUP_XMAX
+      WRITE(X_MAX_PIN,HIGH);
     #endif
-    #if Y_MIN_PIN > -1
-      SET_INPUT(Y_MIN_PIN); 
   #endif
+      
   #if Y_MAX_PIN > -1
     SET_INPUT(Y_MAX_PIN); 
+    #ifdef ENDSTOPPULLUP_YMAX
+      WRITE(Y_MAX_PIN,HIGH);
     #endif
-    #if Z_MIN_PIN > -1
-      SET_INPUT(Z_MIN_PIN); 
   #endif
+  
   #if Z_MAX_PIN > -1
     SET_INPUT(Z_MAX_PIN); 
+    #ifdef ENDSTOPPULLUP_ZMAX
+      WRITE(Z_MAX_PIN,HIGH);
+    #endif
   #endif
-  #endif //ENDSTOPPULLUPS
  
 
   //Initialize Step Pins