1 files changed, 10 insertions, 3 deletions
diff --git a/src/org/traccar/helper/Checksum.java b/src/org/traccar/helper/Checksum.java
index e6b6cd2c8..c156e53f7 100644
--- a/src/org/traccar/helper/Checksum.java
+++ b/src/org/traccar/helper/Checksum.java
@@ -158,13 +158,20 @@ public final class Checksum {
 
     public static String nmea(String msg) {
         int checksum = 0;
-        byte[] bytes = msg.getBytes(Charset.defaultCharset());
-        for (int i = 1; i < msg.length(); i++) {
-            checksum ^= bytes[i];
+        for (byte b : msg.getBytes(Charset.defaultCharset())) {
+            checksum ^= b;
         }
         return String.format("*%02x", checksum).toUpperCase();
     }
 
+    public static String sum(String msg) {
+        byte checksum = 0;
+        for (byte b : msg.getBytes(Charset.defaultCharset())) {
+            checksum += b;
+        }
+        return String.format("%02X", checksum).toUpperCase();
+    }
+
     public static long luhn(long imei) {
         long checksum = 0;
         long remain = imei;