--- a/plcopen/BlockInstanceCollector.py	Mon Oct 09 21:27:17 2023 +0200
+++ b/plcopen/BlockInstanceCollector.py	Thu Oct 12 17:03:44 2023 +0200
@@ -100,7 +100,7 @@
     def __init__(self, block_instances):
         self.BlockInstances = block_instances
         self.CurrentInstance = None
-        self.SpecificValues = None
+        self.SpecificValues = []
         self.CurrentConnection = None
         self.CurrentLink = None