Models 2603, 2621, and 2635 Getting Started Guide | D • IPLink Physical Connectors |
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X.21 (DB-15 Connector)
The X.21 interface in the Model 2621 may be configured for either DTE or DCE. Default is DCE.
Table 10. X.21 Interface (Model 2621)
Pin No. | Circuit |
| Signal Name |
| Direction | |||
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1 | G |
| Signal Ground or Common |
| - | |||
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| Return |
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2 | T |
| Transmit |
| from DTE | |||
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3 | C |
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| from DTE | ||
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4 | R |
| Receive |
| to DTE | |||
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5 | I |
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| to DTE | |||
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6 | S |
| Signal |
| to DTE | |||
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7 | - |
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| - |
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| - |
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8 | Ga |
| DTE Common Return |
| - | |||
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9 | T |
| Transmit |
| from DTE | |||
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10 | C |
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| from DTE | ||
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11 | R |
| Receive |
| to DTE | |||
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12 | I |
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| to DTE | |||
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13 | S |
| Signal |
| to DTE | |||
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14, 15 | - |
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| - |
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| - |
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| Transmit – B | 9 | 1 Frame Ground |
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| 2 | Transmit – A |
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| Control – B | 10 |
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| 3 | Control – A |
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| Receive – B | 11 |
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| 4 | Receive – A |
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| Indication – B | 12 |
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| 5 | Indication – A |
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| Signal Timng – B | 13 |
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| 6 | Signal Timing – A |
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| 14 |
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| 7 |
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| 15 |
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| 8 | Signal Ground |
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Figure 85. X.21 DB-15 connector
Serial port | 127 |