Debug synchronization + add return code

example/receiver.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 
 import sys, random, time
+from esds import RCode
 
 lr=random.Random(6)
 
@@ -17,7 +18,7 @@ def execute(api):
         # Receive until uptime seconds if elapsed
         while api.read("clock") < wakeuntil:
             code, data=api.receivet("wlan0",wakeuntil-api.read("clock"))
-            if code == 0:
+            if code == RCode.SUCCESS:
                 api.log("Receive "+data)
         api.log("Was up for {}s".format(api.read("clock")-wakeat))
         endoff=3600*(i+1)-api.read("clock")