diff --git a/tools/Master.cpp b/tools/Master.cpp
index 9ad94067..4fae1486 100644
--- a/tools/Master.cpp
+++ b/tools/Master.cpp
@@ -1563,7 +1563,8 @@ void Master::generateSlaveXml(uint16_t slavePosition)
             pdoType += "xPdo";
 
             cout
-                << "          <" << pdoType << " Sm=\"" << i << "\">" << endl
+                << "          <" << pdoType
+                << " Sm=\"" << i << "\" Fixed=\"1\">" << endl
                 << "            <Index>#x"
                 << hex << setfill('0') << setw(4) << pdo.index
                 << "</Index>" << endl