Add support for reporting MMU errors via S3 msg

src/main.cpp

@@ -190,6 +190,11 @@ void ReportVersion(const mp::RequestMsg &rq) {
     case 2:
         v = project_version_revision;
         break;
+    case 3:
+        // @@TODO may be allow reporting uint16_t number of errors,
+        // but anything beyond 255 errors means there is something seriously wrong with the MMU
+        v = mg::globals.DriveErrors();
+        break;
     default:
         v = 0;
         break;

src/modules/globals.cpp

@@ -28,5 +28,13 @@ void Globals::SetFilamentLoaded(bool newFilamentLoaded) {
     filamentLoaded = newFilamentLoaded;
 }
 
+uint16_t Globals::DriveErrors() const {
+    return modules::permanent_storage::DriveError::get();
+}
+
+void Globals::IncDriveErrors() {
+    modules::permanent_storage::DriveError::increment();
+}
+
 } // namespace globals
 } // namespace modules

src/modules/globals.h

@@ -33,6 +33,13 @@ public:
     /// @param newFilamentLoaded new state
     void SetFilamentLoaded(bool newFilamentLoaded);
 
+    /// @returns the total number of MMU errors so far
+    /// Errors are stored in the EEPROM
+    uint16_t DriveErrors() const;
+
+    /// Increment MMU errors by 1
+    void IncDriveErrors();
+
 private:
     uint8_t activeSlot;
     bool filamentLoaded;