data terminal ready

from The Free On-line Dictionary of Computing (8 July 2008)

Data Terminal Ready
DTR

   <communications> (DTR) The wire in a full {RS-232} connection
   that tells the {Data Communication Equipment} (DCE, typically
   a {modem}) that the {Data Terminal Equipment} (DTE, typically
   a computer or {terminal}) is ready to transmit and receive
   data.

   (2000-04-05)