Pin # Source Description Comments
1 - Shield 2 DTE Transmit Data A Balanced
3 DCE Receive Data A Balanced
4 DTE Request To Send A Balanced
5 DCE Clear To Send A Balanced
6 DCE DCE Ready A Balanced
7 - Signal Ground AB
8 DCE Received Line Signal Balanced
19 DTE Request To Send B Balanced
20 DTE DTE Ready A Balanced
21 DTE Remote Loopback Unbalanced
22 DCE DCE Ready B Balanced
23 DTE DTE Ready B Balanced
24 DTE External Transmit Timing A Balanced
25 DCE Test Mode Unbalanced

DB-25 Connector. DTE Male Connector

Data Communications for Businesses