Revision as of 22:05, 31 March 2015 edit Jeh (talk \| contribs) Extended confirmed users, Pending changes reviewers 19,611 edits →Signaling for modems: details of AT command set, etc., etc., also irrelevant ← Previous edit		Revision as of 06:38, 1 April 2015 edit undo Jeh (talk \| contribs) Extended confirmed users, Pending changes reviewers 19,611 edits →top: no, that would be logic "1". the relationship of polarity to bit values is opposite for control signals vs data Next edit →
Line 1: '''Data Terminal Ready''' ('''DTR''') is a [[control signal]] in [[RS-232]] serial communications, transmitted from a data terminal (DTE), such as a computer, to a data circuit-terminating device (DCE), for example a [[modem]], to indicate that the terminal is ready for communications and the modem may initiate a communications channel. The DTR signal is present on pin 20 of the 22-wire RS-232 interface using a [[DB-25]] connector, and on pin 4 of a newer [[DE-9]] serial port. The signal is asserted (logic ~~''0''~~"1") by raising the voltage of the pin from negative to positive. Dropping the signal back to its negative state indicates to the modem that the communications session shall be terminated. ==Signaling for modems==

Data Terminal Ready: Difference between revisions