What Do DTE and DCE Mean in Serial Communication?Hardware: Serial, Serial>>RS-232
My National Instruments manual mentions DTE and DCE, but it does not describe the terms in detail. What do these terms mean?
DTE means Data Terminal Equipment; DCE means Data Communications Equipment.
More specifically, DTE and DCE are the two sides of an RS-232 interface. It is important to differentiate between DTE and DCE devices because the pinouts for cables are physically different, as are the descriptions of handshaking and interfacing. A modem is an example of a DCE device. A common DTE device is the serial port of a computer.
Wiring a DTE device to a DCE device for communication is easy. The pins are a one-to-one connection, meaning all wires go from pin x to pin x. A straight through cable is commonly used for this application. In contrast, wiring two DTE devices together requires crossing the transmit and receive wires. This cable is known as a null modem or crossover cable.
For more information on cabling and serial protocol, please see the documents linked below.
NI Developer Zone: Serial Communication Starting Point
Product Manuals: Serial Hardware and Software for Windows User Manual
KnowledgeBase 2N8IEAYF: Auto232 Mode Doesn't Select the Proper RS-232 Transceiver Mode
KnowledgeBase 3GLDMSIT: What is the Difference Between Null Modem and Straight Through Serial Cables?
Report Date: 01/31/2000
Last Updated: 08/30/2007
Document ID: 1TU953QR