RS-232 is used for asynchronous <sync&a.htm> data transfer as well as synchronous links such as SDLC <sdlc.htm>, HDLC <hdlc.htm>, Frame Relay <fr.htm> and X.25 <x25.htm> how is it used for hdlc links? ece. - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org
