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Appendix A
Appendix A: Pin-out Assignments
The rear of the switch has two RJ21 connectors; one for the LINE (also called PBX, PSTN, or System) connections and one for PHONE (also called House or Station) connections. The connector is wired as a 50 pin telco connector, as follows:
RJ21 Line Connectors
Pin 26 | = | line 1 | Tip | |
Pin 1 | = | line 1 | Ring | |
Pin 27 | = | line 2 | Tip | |
Pin 2 | = | line 2 | Ring | |
Pin 50 | = | line 25 | Tip | |
Pin 25 | = | line 25 | Ring |
RS-232 console port
Pin 1 | Unused |
| Pin 6 | Unused |
Pin 2 | TXD – transmit data |
| Pin 7 | Unused |
Pin 3 | RXD – receive data |
| Pin 8 | Unused |
Pin 4 | Unused |
| Pin 9 | Unused |
Pin 5 | GND – signal ground |
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Motorola, Inc. | Page 47 of 51 | |
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