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Figure 63. DB-9 to DB-25 Straight-through Cable Connections
RS-232 Crossover DB-9 to DB-25 Conversion Connections
RS-232 DTE Loopback Connections
Figure 65. Loopback Connections for RS-232
For Transmit and Receive loopback, connect only those lines.
When Flow Control setting on the Serial Server is set for RTS/CTS, those lines must be looped. Usually DTR and DSR must also be looped. The Flow Control setting for the program must match the Server settings. The CD connection is needed by some terminal programs to simulate Carrier.
Figure 64. DB-9 to DB-25 Crossover (null modem) Cable Connections
Manual Documentation Number: | Appendix A | 73 | 74 | 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 | – |