diff --git a/Grbl_Esp32/Custom/4axis_xyza.cpp b/Grbl_Esp32/Custom/4axis_xyza.cpp
index 47f2aa06..5dc6921b 100644
--- a/Grbl_Esp32/Custom/4axis_xyza.cpp
+++ b/Grbl_Esp32/Custom/4axis_xyza.cpp
@@ -38,8 +38,8 @@ void user_defined_macro(uint8_t index) {
 
     if (msPassedBy >= DEBOUNCE_TIME_MACRO_1) {
         switch (index) {
-            case 0:  // Macro button 1 (Hold/Cycle switch)
 
+            case 0:  // Macro button 1 (Hold/Cycle switch)
                 switch (sys.state) {
                     case State::Hold:
                         grbl_sendf(CLIENT_ALL, "Macro button #%d pressed. New state \"Cyle start\"\r\n", index + 1);
@@ -74,6 +74,30 @@ void user_defined_macro(uint8_t index) {
                 }
                 break;
 
+            case 2:  // Macro button 3 (Z Probe)
+                if (sys.state == State::Idle) {
+                    grbl_sendf(CLIENT_ALL, "Macro button #%d pressed. Z probe\r\n", index + 1);
+
+					// use datum plane XY, mm unit of measure, relative addresing mode
+                    grbl_sendf(CLIENT_ALL, "G17 G21 G91\r\n");
+                    WebUI::inputBuffer.push("G21 G91\r\n");
+
+					// Go 25mm deeper to hopefully hit alu plate
+                    grbl_sendf(CLIENT_ALL, "G38.2 Z-25.0 F50\r\n");
+                    WebUI::inputBuffer.push("G38.2 Z-25.0 F50\r\n");
+
+                    // Plate thickness 20mm, so adjust Z hG54 height
+                    grbl_sendf(CLIENT_ALL, "G10 L20 P0 Z+20\r\n");
+                    WebUI::inputBuffer.push("G10 L20 P0 Z+20\r\n");  // Set G54, only Z axis, on workpiece level, 20mm below alu plate
+
+					Move up
+                    grbl_sendf(CLIENT_ALL, "G53 G0 Z-5 F200\r\n");
+                    WebUI::inputBuffer.push("G53 G0 Z-5 F200\r\n");  // Z up
+                } else {
+                    grbl_sendf(CLIENT_ALL, "Macro button #%d pressed. Works only in state \"Idle\"\r\n", index + 1);
+                }
+                break;
+
             default:
                 break;
         }
diff --git a/Grbl_Esp32/Machines/4axis_xyza.h b/Grbl_Esp32/Machines/4axis_xyza.h
index 0fd5fbf2..11c2b098 100644
--- a/Grbl_Esp32/Machines/4axis_xyza.h
+++ b/Grbl_Esp32/Machines/4axis_xyza.h
@@ -70,12 +70,13 @@
  */
 #define PROBE_PIN               GPIO_NUM_35 //ok
 //#define CONTROL_SAFETY_DOOR_PIN GPIO_NUM_36  // needs external pullup
-#define CONTROL_RESET_PIN       GPIO_NUM_34  // needs external pullup
+//#define CONTROL_RESET_PIN       GPIO_NUM_34  // needs external pullup
 //#define CONTROL_FEED_HOLD_PIN   GPIO_NUM_36  // needs external pullup
 //#define CONTROL_CYCLE_START_PIN GPIO_NUM_39  // needs external pullup
 
 #define MACRO_BUTTON_0_PIN      GPIO_NUM_36
 #define MACRO_BUTTON_1_PIN      GPIO_NUM_39
+#define MACRO_BUTTON_2_PIN      GPIO_NUM_34
 
 /* Normally Grbl_ESP32 ignores tool changes.
  * It just tracks the current tool number.
diff --git a/Grbl_Esp32/src/Config.h b/Grbl_Esp32/src/Config.h
index 2fd8dffb..ac9ad884 100644
--- a/Grbl_Esp32/src/Config.h
+++ b/Grbl_Esp32/src/Config.h
@@ -54,7 +54,7 @@ Some features should not be changed. See notes below.
 // The mask order is ...
 // Macro3 | Macro2 | Macro 1| Macr0 |Cycle Start | Feed Hold | Reset | Safety Door
 // For example B1101 will invert the function of the Reset pin.
-#define INVERT_CONTROL_PIN_MASK B00111111
+#define INVERT_CONTROL_PIN_MASK B01111111
 
 // #define ENABLE_CONTROL_SW_DEBOUNCE     // Default disabled. Uncomment to enable.
 #define CONTROL_SW_DEBOUNCE_PERIOD 32  // in milliseconds default 32 microseconds