See which switch caused the hard limit

- Used for debugging
- Set Message/Level=Debug to activate

looks like this...

[MSG:Pn:X]
ALARM:1

Grbl_Esp32/src/Limits.cpp

@@ -52,6 +52,11 @@ void IRAM_ATTR isr_limit_switches() {
             int evt;
             xQueueSendFromISR(limit_sw_queue, &evt, NULL);
 #else
+            // Debugging...Show what axis triggered the ISR
+            if (static_cast<MsgLevel>(message_level->get()) == MsgLevel::Debug) {
+                grbl_msg_sendf(CLIENT_ALL, MsgLevel::Debug, "Pn:%s", maskToString(limits_get_state()));
+            }
+
 #    ifdef HARD_LIMIT_FORCE_STATE_CHECK
             // Check limit pin state.
             if (limits_get_state()) {

Grbl_Esp32/src/Report.cpp

@@ -956,4 +956,14 @@ void reportTaskStackSize(UBaseType_t& saved) {
 #endif
 }
 
+String maskToString(uint32_t mask) {
+    String str = "";
+    for (int i = 0; i < MAX_N_AXIS; i++) {
+        if (mask & bit(i)) {
+            str += "XYZABC"[i];
+        }
+    }    
+    return str;
+}
+
 void __attribute__((weak)) forward_kinematics(float* position) {}  // This version does nothing. Make your own to do something with it

Grbl_Esp32/src/Report.h

@@ -129,3 +129,5 @@ char* reportAxisNameMsg(uint8_t axis);
 char* reportAxisNameMsg(uint8_t axis, uint8_t dual_axis);
 
 void reportTaskStackSize(UBaseType_t& saved);
+
+String maskToString(uint32_t mask);