diff --git a/connection/connection.go b/connection/connection.go
index b2dd7db..fa0d846 100644
--- a/connection/connection.go
+++ b/connection/connection.go
@@ -34,8 +34,9 @@ const (
 type ConnType int
 
 const (
-	ConnTypeTCP ConnType = iota // TCP connection
-	ConnTypeWS                  // Websocket connection
+	ConnTypeTCP    ConnType = iota // TCP connection
+	ConnTypeWS                     // Websocket connection
+	ConnTypeSerial                 // Websocket connection
 )
 
 type (
@@ -102,9 +103,13 @@ func NewConnection(
 		chSend:  make(chan PendingMessage, 128),
 		chWrite: make(chan []byte, 128),
 	}
-	_, ok := conn.(*WSConn)
-	if ok {
+	if _, ok := conn.(*WSConn); ok {
 		r.typ = ConnTypeWS
+		return r
+	}
+	if _, ok := conn.(*SerialConn); ok {
+		r.typ = ConnTypeSerial
+		return r
 	}
 	return r
 }