diff --git a/BrainATUMtome/serialpackage.cpp b/BrainATUMtome/serialpackage.cpp
index 713d701..07ce36a 100644
--- a/BrainATUMtome/serialpackage.cpp
+++ b/BrainATUMtome/serialpackage.cpp
@@ -6,23 +6,38 @@ SerialPackage::SerialPackage()
 }
 
 
-bool SerialPackage::parse(QString &message)
+QString SerialPackage::parse(bool &ok, const QString &message)
 {
+    QString buffer = message;
+
     // clean message
-    message = message.simplified();
+    buffer = buffer.simplified();
 
-    if (message.at(0) == '!')
-        message.remove(0, 1);
+    if (buffer.at(0) == '!')
+        buffer.remove(0, 1);
 
     // check for even size
-    if ((message.size() % 2) != 0)
-        return false;
+    if ((buffer.size() % 2) != 0)
+        ok = false;
+
+    // check received checksum
+    quint8 checksumReceived = 0;
+    if (!unpack(checksumReceived, buffer.mid(buffer.size() - 2, 2)))
+        ok = false;
+    ok = (checksumReceived == checksum(message));
+
+    // remove checksum from buffer
+    buffer.remove(buffer.size() - 2, 2);
+
+    return buffer;
+}
 
-    // get received checksum
-    quint8 checksumReceived = static_cast<quint8>(QString("%1%2").arg(message.mid(message.size() - 2, 1), message.mid(message.size() - 1, 1)).toUInt(nullptr, 16));
-    message.remove(message.size() - 2, 2);
 
-    return (checksumReceived == checksum(message));
+QString SerialPackage::package(const QString &message)
+{
+    quint8 checksumValue = checksum(message);
+    QString checksumText = pack(checksumValue);
+    return '!' + message + checksumText + '\r';
 }
 
 
diff --git a/BrainATUMtome/serialpackage.h b/BrainATUMtome/serialpackage.h
index 1966394..f1cc972 100644
--- a/BrainATUMtome/serialpackage.h
+++ b/BrainATUMtome/serialpackage.h
@@ -9,7 +9,8 @@ class SerialPackage
 public:
     explicit SerialPackage();
 
-    static bool parse(QString &message);
+    static QString parse(bool &ok, const QString &message);
+    static QString package(const QString &message);
 
     static quint8 address(const QString &message);
     static quint8 command(const QString &message);