diff --git a/src/dataformatpanel.cpp b/src/dataformatpanel.cpp
--- a/src/dataformatpanel.cpp
+++ b/src/dataformatpanel.cpp
@@ -1,5 +1,5 @@
 /*
-  Copyright © 2018 Hasan Yavuz Özderya
+  Copyright © 2019 Hasan Yavuz Özderya
 
   This file is part of serialplot.
 
@@ -39,6 +39,7 @@ DataFormatPanel::DataFormatPanel(QSerial
     serialPort = port;
     paused = false;
     readerBeforeDemo = nullptr;
+    _bytesRead = 0;
 
     // initalize default reader
     currentReader = &bsReader;
@@ -130,6 +131,12 @@ void DataFormatPanel::selectReader(Abstr
     emit sourceChanged(currentReader);
 }
 
+uint64_t DataFormatPanel::bytesRead()
+{
+    _bytesRead += currentReader->getBytesRead();
+    return _bytesRead;
+}
+
 void DataFormatPanel::saveSettings(QSettings* settings)
 {
     settings->beginGroup(SettingGroup_DataFormat);