The Allied Telesyn iQ1000 is a router that exposes an 8-pin RJ-45 serial port for local management access. A dedicated cable adapts this modular connector to the 9-pin DE-9 (DB-9) COM port of a PC or terminal, following the EIA-232 (TIA/EIA-232-F) serial signalling standard that governs binary data interchange between DTE and DCE devices. The arrangement is typical of late-1990s network equipment where vendors adopted RJ-45 modular connectors for console ports rather than placing a full-size D-sub directly on the chassis. DSR is not wired in this cable.
8 pin RJ45 (8P8C) male connector to the router
9 pin D-SUB female connector to the computer
| Router Port 0 Pin name | Router Port 0 Pin | Direction | PC or terminal serial port Pin | PC or terminal serial port Pin name | Description |
|---|---|---|---|---|---|
| 1 | 9 | RI | Ring Indicator | ||
| 2 | IN | 4 | DTR | Data Terminal Ready | |
| 3 | OUT | 1 | CD | Carrier Detect | |
| 4 | - | 5 | GND | Signal Ground | |
| 5 | IN | 3 | TXD | Transmit Data | |
| 6 | 2 | RXD | Receive Data | ||
| 7 | 7 | RTS | Request to Send | ||
| 8 | 8 | CTS | Clear to Send |
Notes
- DSR (Data Set Ready) is not connected in this cable.
- The router end uses an 8-pin RJ-45 (8P8C) modular plug; the computer end uses a 9-pin DE-9 female connector compatible with standard PC COM ports.
- Terminal settings: 9600 baud, 8 data bits, no parity, 1 stop bit (8N1) is typical for equipment of this era, though the iQ1000 manual has not been publicly located to confirm.
Signals
- RI — Ring Indicator; signals an incoming call on the PC COM port (RJ-45 pin 1 to DE-9 pin 9).
- DTR — Data Terminal Ready; asserted by the PC to indicate readiness (DE-9 pin 4 to RJ-45 pin 2).
- CD — Carrier Detect; indicates a carrier has been detected (RJ-45 pin 3 to DE-9 pin 1).
- GND — Signal Ground; common reference for all signals (RJ-45 pin 4 to DE-9 pin 5).
- TXD — Transmit Data; data sent from the PC to the router (DE-9 pin 3 to RJ-45 pin 5).
- RXD — Receive Data; data sent from the router to the PC (RJ-45 pin 6 to DE-9 pin 2).
- RTS — Request to Send; hardware flow control from the PC (RJ-45 pin 7 to DE-9 pin 7).
- CTS — Clear to Send; hardware flow control from the router (RJ-45 pin 8 to DE-9 pin 8).
- DSR — Data Set Ready; not connected in this cable.
References
- TIA/EIA-232-F — Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange (Telecommunications Industry Association); RJ-45-to-DE-9 asynchronous console mapping.