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PINOUTs for DB25 WAN Cable
RS-232 (DB-25) Serial Connector Pinouts
Signal/Voltage
Source Signal Designations Pin
#
Pin
# Signal Designations Signal/Voltage
Source
DTE Secondary Transmitted Data 14 1 Sheild Common
DCE Transmit Clock 15 2 TD Transmit Data DTE
DCE Secondary Receive Data 16 3 RD Received Data DCE
DCE Receiver Clock 17 4 RTS Request To Send DTE
DTE Local Loopback 18 5 CTS Clear To Send DCE
DTE Request To Send (Return) 19 6 DSR DCE Ready DCE
DTE Data Terminal Ready 20 7 Signal Ground Common
- Remote Loopback 21 8 DCD Rcv'd Line Signal Detect DCE
DCE Ring Indicator 22 9 (+) DC Test Voltage DCE
- Data Signal Rate Selector 23 10 (-) DC Test Voltage DCE
DTE Transmit Clock 24 11 Unassigned -
DCE Test Mode 25 12 SCF/CI Secondary Rcv'd Line DCE
13 Secondary Clear To Send DCE
V.35 (DB-25) Serial Connector Pinouts
Signal/Voltage
Source Signal Designations Pin
#
Pin
# Signal Designations Signal/Voltage
Source
DCE Test Mode 25 13 - -
DTE External Transmit Clock (a) 24 12 Tranmit Clock (b) DTE
- -
23 11 External Transmit Clock (b) DTE
- -
22 10 - -
DTE Remote Loopback 21 9 Receive Clock (b) DCE
DTE Data Terminal Ready 20 8 Carrier Detect DCE
- -
19 7 Signal Ground -
DTE Local Loopback 18 6 Data Set Ready DCE
DCE Receive Clock (a) 17 5 Clear To Send DCE
DCE Receive Data (b) 16 4 Request To Send DTE
DCE Transmit Clock (a) 15 3 Receive Data (a) DCE
DTE Transmit Data (b) 14 2 Transmit Data (a) DTE
1 Frame Ground -
RS-530 (DB-25) Serial Connector Pinouts
Signal/Voltage
Source Signal Designations Pin
#
Pin
# Signal Designations Signal/Voltage
Source
Common Transmitted Data (Return) 14 1 Sheild Common
DCE Transmit Clock 15 2 Transmitted Data DTE
Common Received Data (Return) 16 3 Rreceived Data DCE
DCE Receiver Clock 17 4 Request To Send DTE
DTE Local Loopback 18 5 Clear To Send DCE
Common Request To Send (Return) 19 6 DCE Ready DCE
DTE Data Terminal Ready 20 7 Signal Ground Common
DTE Remote Loopback 21 8 Carrier Detect DCE
Common Data Set Ready (Return) 22 9 Receiver Clock (Return) Common
Common Data Terminal Ready (Return) 23 10 Carrier Detect (Return) Common
DTE DTE Transmitter Clock 24 11 DTE Transmitter Clock (Return) Common
DCE Test Mode 25 12 Transmitter Clock (Return) Common
13 Clear to Send (Return) Common