diff --git a/armsrc/Makefile b/armsrc/Makefile
index fe34c8a8f..d6ab2bfc4 100644
--- a/armsrc/Makefile
+++ b/armsrc/Makefile
@@ -127,7 +127,7 @@ THUMBSRC = start.c \
     $(SRC_SMARTCARD) \
     $(SRC_FPC) \
     $(SRC_HITAG) \
-	$(SRC_EM4x50) \
+    $(SRC_EM4x50) \
     $(SRC_EM4x70) \
     $(SRC_SPIFFS) \
     $(SRC_HF) \