array to hex function, reduced usb timeout
diff --git a/usb_application/util.py b/usb_application/util.py
new file mode 100644
index 0000000..b6ef5a7
--- /dev/null
+++ b/usb_application/util.py
@@ -0,0 +1,5 @@
+
+def HEX(vals):
+    if vals is not None:
+        return ' '.join('%.2x'%x for x in vals)
+