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APPENDIX A: RS-232 CONNECTIONS
Serial Server DB-9 Pin-outs in RS-232 Mode
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DTE | |||
Signal Name |
|
| Pin |
Carrier Detect | In | DCD | 1 |
Receive Data | In | RXD | 2 |
Transmit Data | Out | TXD | 3 |
Data Terminal Ready | Out | DTR | 4 |
Signal Ground | GND | 5 | |
Data Set Ready | In | DSR | 6 |
Request To Send | Out | RTS | 7 |
Clear To Send | In | CTS | 8 |
Ring Indicator | In | RI | 9 |
Figure 60. RS-232 Connections in a DB-9 Connector
Manual Documentation Number: | Appendix A | 71 |
RS-232 Straight-through Cable Connections
In the
| Connections | Signal | ||||
|
|
| Pin# |
| Pin# |
|
Carrier Detect |
| CD | 1 |
| 1 | CD |
Receive Data |
| RD | 2 |
| 2 | RD |
Transmit Data |
| TD | 3 |
| 3 | TD |
Data Terminal Ready |
| DTR | 4 |
| 4 | DTR |
Signal Ground/Common |
| GND | 5 |
| 5 | GND |
Data Set Ready |
| DSR | 6 |
| 6 | DSR |
Request to Send |
| RTS | 7 |
| 7 | RTS |
Clear to Send |
| CTS | 8 |
| 8 | CTS |
Ring Indicator |
| RI | 9 |
| 9 | RI |
Figure 61. Straight-through DB-9 to DB-9 RS-232 Serial Cable
RS-232 Crossover (null modem) Cable Connections
When connecting to a PC or another DTE device, use a crossover cable (also called a null modem cable).
| Connections | |||
|
| Pin# | Pin# |
|
Carrier Detect | CD | 1 | 1 | CD |
Receive Data | RD | 2 | 2 | RD |
Transmit Data | TD | 3 | 3 | TD |
Data Terminal Ready | DTR | 4 | 4 | DTR |
Signal Ground/Common | GND | 5 | 5 | GND |
Data Set Ready | DSR | 6 | 6 | DSR |
Request to Send | RTS | 7 | 7 | RTS |
Clear to Send | CTS | 8 | 8 | CTS |
Ring Indicator | RI | 9 | 9 | RI |
Figure 62.Crossover DB-9 to DB-9 RS-232 Serial Cable
72 | Appendix A | Manual Documentation Number: |
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph | – | B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph | – |
B&B Electronics Ltd – Westlink Commercial Pk – Oranmore, Galway, Ireland – Ph +353 | – | B&B Electronics Ltd – Westlink Commercial Pk – Oranmore, Galway, Ireland – Ph +353 | – |