diff --git a/artiq/examples/kasli_tester/device_db.py b/artiq/examples/kasli_tester/device_db.py
index c44707314..2af42ea07 100644
--- a/artiq/examples/kasli_tester/device_db.py
+++ b/artiq/examples/kasli_tester/device_db.py
@@ -187,6 +187,6 @@ device_db.update(
 )
 
 device_db.update(
-    "ttl_out": "ttl4",
-    "ttl_out_serdes": "ttl4",
+    ttl_out="ttl4",
+    ttl_out_serdes="ttl4",
 )