diff --git a/builder/main.py b/builder/main.py
index 01a8f9f..4576448 100644
--- a/builder/main.py
+++ b/builder/main.py
@@ -197,6 +197,7 @@ elif upload_protocol.startswith("jlink"):
         UPLOADCMD='$UPLOADER $UPLOADERFLAGS -CommanderScript "${__jlink_cmd_script(__env__, SOURCE)}"'
     )
     upload_actions = [env.VerboseAction("$UPLOADCMD", "Uploading $SOURCE")]
+    upload_source = env.ElfToHex(join("$BUILD_DIR", "${PROGNAME}"), target_elf)
 
 elif upload_protocol in debug_tools:
     openocd_args = [