From 1a8d764d5ca9b73480a230c518b302aa5533cc0e Mon Sep 17 00:00:00 2001
From: Frey Mansikkaniemi <frey@asiaweb.invite.hk>
Date: Mon, 31 Aug 2020 07:22:26 +0000
Subject: [PATCH] Fixed checksum from lower case to upper case letters.

---
 its-fps-qrcodedata-class.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/its-fps-qrcodedata-class.php b/its-fps-qrcodedata-class.php
index a959e63..ff2f694 100644
--- a/its-fps-qrcodedata-class.php
+++ b/its-fps-qrcodedata-class.php
@@ -15,7 +15,7 @@ if( !class_exists('ITS_FPS_QRCodeData') ){
         public function getDataString(){
             $msg = $this->emvString($this->data);
             $crc = $this->pad(dechex($this->crc16ccitt($msg)),4);
-            return $msg . $crc;
+            return $msg . strtoupper($crc);
         }
     
         private function pad($s, $size = 2) {
@@ -146,4 +146,4 @@ if( !class_exists('ITS_FPS_QRCodeData') ){
     }
 }
 
-?>
\ No newline at end of file
+?>