If flow control is disabled you just need to connect 2-3 on the USB-serial adapter (DB-9 male)
http://us.brainboxes.com/faq/items/how-do-i-create-a-loop-back-connector
If flow control is disabled you just need to connect 2-3 on the USB-serial adapter (DB-9 male)
http://us.brainboxes.com/faq/items/how-do-i-create-a-loop-back-connector