Index: sources/canbus/messagebuilder.h
===================================================================
diff -u -rfee7fabf49befb065c89248c19e15efc9ca194e4 -rc5389647e2259e67f8e6d923f3481d7d3f4eab68
--- sources/canbus/messagebuilder.h	(.../messagebuilder.h)	(revision fee7fabf49befb065c89248c19e15efc9ca194e4)
+++ sources/canbus/messagebuilder.h	(.../messagebuilder.h)	(revision c5389647e2259e67f8e6d923f3481d7d3f4eab68)
@@ -53,19 +53,19 @@
     bool           _enableConsoleOut   = false;
 
     void          addSyncByte (      QByteArray &vPayload);
-    void          addActionId (      QByteArray &vPayload, GuiActionType vAction);
-    void          addData     (      QByteArray &vPayload, GuiActionType vAction, const QByteArray &vData);
+    bool          addActionId (      QByteArray &vPayload, GuiActionType vAction)                           __attribute_warn_unused_result__;
+    bool          addData     (      QByteArray &vPayload, GuiActionType vAction, const QByteArray &vData)  __attribute_warn_unused_result__;
     void          addCRC      (      QByteArray &vPayload);
     void          addPadding  (      QByteArray &vPayload);
 
-    quint8        calcCRC     (const QByteArray &vData);
-    bool          checkCRC    (const QByteArray &vData);
+    quint8        calcCRC     (const QByteArray &vData   );
+    bool          checkCRC    (const QByteArray &vData   , quint8 &vExpected, quint8 &vBeenRead);
 
     bool          hasSyncByte (      QByteArray &vPayload);
     QByteArray    getHeader   (const QByteArray &vPayload);
     GuiActionType getActionId (      QByteArray &vPayload);
     int           getLength   (      QByteArray &vPayload);
-    QByteArray    getData     (      QByteArray &vPayload, int vLen);
+    QByteArray    getData     (const QByteArray &vPayload, int vLen);
 
     void          printPayload(const QByteArray &vPayload, bool vIsHeader, Can_Id vCan_Id, bool vUseColor = true);
     void          consoleOut  (const QByteArray &vPayload, bool vIsHeader, Can_Id vCan_Id, bool vUseColor = true);
@@ -74,9 +74,9 @@
     explicit MessageBuilder(QObject *parent = nullptr);
 
     // build message to be sent frame by frame
-    FrameList     buildFrames (       GuiActionType vAction , const QByteArray &vData);
+    bool           buildFrames(GuiActionType vAction , const QByteArray &vData, FrameList &vFrameList)      __attribute_warn_unused_result__;
     // build message from received frames
-    bool          buildMessage (const QByteArray   &vPayload, Message &vMessage, Can_Id vCan_Id);
+    bool          buildMessage(const QByteArray   &vPayload, Message &vMessage, Can_Id vCan_Id)             __attribute_warn_unused_result__;
 
     void       enableConsoleOut(      bool          vEnabled) { _enableConsoleOut = vEnabled; }