diff --git a/src/wifi_transport.cpp b/src/wifi_transport.cpp
index ace70ab51..0c0c66aee 100755
--- a/src/wifi_transport.cpp
+++ b/src/wifi_transport.cpp
@@ -56,7 +56,7 @@ extern "C"
       delay(1);
     }
 
-    size_t readed  = udp_client.read(buf, len);
+    int readed  = udp_client.read(buf, len);
 
     return (readed < 0) ? 0 : readed;
   }