diff --git a/edalize/tools/vcs.py b/edalize/tools/vcs.py
index ebdeaa8c..40ac1f45 100644
--- a/edalize/tools/vcs.py
+++ b/edalize/tools/vcs.py
@@ -181,7 +181,7 @@ def write_config_files(self):
         parameters = []
         s = ""
         for key, value in _parameters.items():
-            s += f"assign {key} {self._param_value_str(value)}"
+            s += f'assign {key} {self._param_value_str(value, "")}\n'
         self.update_config_file("parameters.txt", s)
 
     def run(self):