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DB-9 Port Pin Assignments
EIA | CCITT | Description | Gateway’s | Computer | Modem | Signal |
Circuit | Signal |
| DB9 DTE | DB9 DTE | DB25 DCE | Direction |
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| Pin # | Pin # | Pin # |
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CF | 109 | DCD (Data Carrier | 1 | 1 | 8 | |
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BB | 104 | RxD (Received Data) | 2 | 2 | 3 | |
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BA | 103 | TxD (Transmitted Data) | 3 | 3 | 2 | |
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CD | 108.2 | DTR (Data Terminal Ready) | 4 | 4 | 20 | |
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AB | 102 | SG (Signal Ground) | 5 | 5 | 7 | |
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CC | 107 | DSR (Data Set Ready) | 6 | 6 | 6 | |
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CA | 105 | RTS | 7 | 7 | 4 | |
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CB | 106 | CTS | 8 | 8 | 5 | |
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CE | 125 | RI (Ring Indicator) | 9 | 9 | 22 | |
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Table
Serial Port to 9-Pin COM Port on Computer
| SpeedStream 2614’s | CCITT Signal |
| Computer’s | |
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| 1 DCD | DCD | 1 | ||
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| 2 RXD | TXD | 3 | ||
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| 3 TXD | RXD | > | 2 | |
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| 4 DTR | DSR | > | 6 | |
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| 5 SGND | SGND | 5 | ||
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| 6 DSR | DTR | 4 | ||
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| 7 RTS | CTS | > | 8 | |
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| 8 CTS | RTS | 7 | ||
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| 9 RI | RI | 9 | ||
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| Table | ||||
Serial Port to |
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| SpeedStream 2614’s | CCITT Signal |
| Modem’s | |
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| 1 | DCD | 8 | ||
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| 2 | RXD | 3 | ||
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| 3 | TXD | > | 2 | |
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| 4 | DTR | > | 20 | |
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| 5 | SGND | 7 | ||
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| 6 | DSR | 6 | ||
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| 7 | RTS | > | 4 | |
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| 8 | CTS | 5 | ||
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| 9 | RI | 22 | ||
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Table