diff --git a/examples/eg_protocols.pdl b/examples/eg_protocols.pdl
index a545ea70afb988c8600f4cdf12f68d4e5f8c5749..4de6b59a35c1d45e788bee6a58ec0f1a5e9f8c8b 100644
--- a/examples/eg_protocols.pdl
+++ b/examples/eg_protocols.pdl
@@ -1,6 +1,6 @@
 primitive pres_2(in i, out o) {
   synchronous {
-    //put(o, get(i));
+    put(o, get(i));
   }
 }
 primitive together(in ia, in ib, out oa, out ob){
@@ -11,3 +11,10 @@ primitive together(in ia, in ib, out oa, out ob){
     }
   }	
 }
+
+primitive alt_round_merger(in a, in b, out c){
+  while(true) {
+    synchronous{ put(c, get(a)); }
+    synchronous{ put(c, get(b)); }
+  }	
+}