diff --git a/lib/mfrc522/source/loop.php b/lib/mfrc522/source/loop.php
index b11aea8..52be934 100755
--- a/lib/mfrc522/source/loop.php
+++ b/lib/mfrc522/source/loop.php
@@ -27,7 +27,7 @@
 	function get_gstate(){
 
 		/* (1) Export global file descriptor */
-		global $g_gstate;
+		global $f_gstate;
 
 		/* (2) Read first line */
 		$f_gstate->seek(0);