diff --git a/build/tests/CustomSystemUpdater/romchecker.rb b/build/tests/CustomSystemUpdater/romchecker.rb
index ec79aa8f..327c6aff 100755
--- a/build/tests/CustomSystemUpdater/romchecker.rb
+++ b/build/tests/CustomSystemUpdater/romchecker.rb
@@ -16,20 +16,20 @@
 #----------------------------------------------------------------------------
 
 ALL_REGION = [
-    "c", "d", "e", "h",
+    "C", "D", "E", "H",
 ]
 
 FIX_REGION = [
-    "a", "b", "f", "g", "i", "j", "k", "l",
+    "A", "B", "F", "G", "I", "J", "K", "L",
 ]
 
-HEADER = "hn"
+HEADER = "HN"
 
 REGION_DIRS = {
-    "aus" => "u",
-    "euro" => "p",
-    "jp" => "j",
-    "usa" => "e",
+    "aus" => "U",
+    "euro" => "P",
+    "jp" => "J",
+    "usa" => "E",
 }
 
 REG_PATH = /[a-zA-Z0-9\.\-_]+\/[a-zA-Z0-9\.\-_*]+\z/