Data circuit-terminating equipment
A data circuit-terminating equipment[1] (DCE) is a device that sits between the data terminal equipment (DTE) and a data transmission circuit. It is also called data communication(s) equipment[2][3][4] and data carrier equipment.[citation needed] Usually, the DTE device is the terminal (or computer), and the DCE is a modem.
In a data station, the DCE performs functions such as signal conversion, coding, and line clocking and may be a part of the DTE or intermediate equipment.[3] Interfacing equipment may be required to couple the DTE into a transmission circuit or channel and from a transmission circuit or channel into the DTE.
Usage
[edit | edit source]Although the terms are most commonly used with RS-232, several data communication standards define different types of interfaces between a DCE and a DTE. The DCE is a device that communicates with a DTE device in these standards. Standards that use this nomenclature include:
- Federal Standard 1037C, MIL-STD-188
- RS-232
- Certain ITU-T standards in the V series (notably V.24 and V.35)
- Certain ITU-T standards in the X series (notably X.21 and X.25)
A general rule is that DCE devices provide the clock signal (internal clocking) and the DTE device synchronizes on the provided clock (external clocking). D-sub connectors follow another rule for pin assignment. DTE devices usually transmit on pin connector number 2 and receive on pin connector number 3. DCE devices are just the opposite: pin connector number 2 receives and pin connector number 3 transmits the signals.
When two devices, that are both DTE or both DCE, must be connected together without a modem or a similar media translator between them, a crossover cable must be used, e.g. a null modem for RS-232 or an Ethernet crossover cable.
See also
[edit | edit source]References
[edit | edit source]- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ MIL-STD-188-100, pg. 24, Fig 4.3-1, 1972.
External links
[edit | edit source]
Lua error in Module:Authority_control at line 153: attempt to index field 'wikibase' (a nil value).