diff --git a/src/wifi_transport.cpp b/src/wifi_transport.cpp
index bce8ff9a9..a295e60c0 100755
--- a/src/wifi_transport.cpp
+++ b/src/wifi_transport.cpp
@@ -58,7 +58,7 @@ extern "C"
       delay(1);
     }
 
-    size_t readed  = udp_client.read(buf, len);
+    int readed  = udp_client.read(buf, len);
 
     return (readed < 0) ? 0 : readed;
   }