--- src/dfu_load.c	2016-07-31 16:40:06.942373144 +0800
+++ src/dfu_load.cc	2016-07-31 16:39:42.493105664 +0800
@@ -132,6 +132,7 @@
		bytes_sent += ret;

		do {
+			milli_sleep(200);
			ret = dfu_get_status(dif->dev_handle, dif->interface, &dst);
			if (ret < 0) {
				fprintf(stderr, "Error during download get_status\n");