Introduction
This document explains the different ports and adapter pintouts for Cisco 1000, 1600, 2500, 2600, and 3600 Series Routers.
Prerequisites
Requirements
There are no specific requirements for this document.
Components Used
The information in this document is based on these software and hardware versions:
-
Cisco 1000, 1600, 2500, 2600, and 3600 Series Routers
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
Conventions
Refer to Cisco Technical Tips Conventions for more information on document conventions.
Auxiliary and Console Ports
The console and auxiliary ports on Cisco IOS® routers are asynchronous serial ports. The console port and the auxiliary port are configured as data terminal equipment (DTE). For Cisco 1000, 1600, 2500, 2600, and 3600 Series Routers, the console and auxiliary ports both use RJ-45 connectors. Adapters are available for connections to PC terminals, modems, or other external communications equipment.
This table shows the console port pinouts for the RJ-45 connector:
| Console Port (DTE) | ||
|---|---|---|
| Pin1 | Signal | Input/Output |
| 1 | - | - |
| 2 | DTR | Output |
| 3 | TxD | Output |
| 4 | GND | - |
| 5 | GND | - |
| 6 | RxD | Input |
| 7 | DSR | Input |
| 8 | - | - |
1Any pin not referenced is not connected.
This table shows the auxiliary port pinouts of the RJ-45 connector:
| Auxiliary Port (DTE) | ||
|---|---|---|
| Pin2 | Signal | Input/Output |
| 1 | RTS | Output |
| 2 | DTR | Output |
| 3 | TXD | Output |
| 4 | GND | - |
| 5 | GND | - |
| 6 | RXD | Input |
| 7 | DSR | Input |
| 8 | CTS | Input |
2Any pin not referenced is not connected.
Identify a Rollover Cable
In order to identify a rollover cable, compare the two modular ends of the cable. Hold the cables in your hand, side-by-side, with the tab at the back. The wire connected to the pin on the outside of the left connector (pin 1) must be the same color as the pin on the outside of the right connector (pin 8). On Cisco cables, pin 1 is white on one connector, and pin 8 is white on the other connector.
This table shows the RJ-45 rolled (console) cable pinouts:
| Signal | Pin | Pin | Signal |
|---|---|---|---|
| - | 1 | 8 | - |
| - | 2 | 7 | - |
| - | 3 | 6 | - |
| - | 4 | 5 | - |
| - | 5 | 4 | - |
| - | 6 | 3 | - |
| - | 7 | 2 | - |
| - | 8 | 1 | - |
Console Port Connection to a PC
To connect a PC terminal to the console port, use the RJ-45-to-RJ-45 rollover cable, and either the RJ-45-to-DB-25 female DTE adapter or the RJ-45-to-DB-9 female DTE adapter (labeled "TERMINAL").
The default parameters for the console port are:
-
9600 baud
-
8 data bits
-
No parity generated or checked
-
1 stop bit
-
No Flow Control
Console Port Signaling and Cabling with a DB-9 Adapter
The next table shows the pinout descriptions for the DB-9 connections:
| Console Port (DTE) | RJ-45-to-RJ-45 Rollover Cable | RJ-45-to-DB-9 Terminal Adapter | Console Device | |
|---|---|---|---|---|
| Signal | RJ-45 Pin | RJ-45 Pin | DB-9 Pin | Signal |
| RTS | 13 | 8 | 8 | CTS |
| DTR | 2 | 7 | 6 | DSR |
| TxD | 3 | 6 | 2 | RxD |
| GND | 4 | 5 | 5 | GND |
| GND | 5 | 4 | 5 | GND |
| RxD | 6 | 3 | 3 | TxD |
| DSR | 7 | 2 | 4 | DTR |
| CTS | 8 | 1 | 7 | RTS |
3Pin 1 is connected internally to Pin 8.
Console Port Signaling and Cabling with a DB-25 Adapter
The next table shows the pinout descriptions for the DB-25 connections:
| Console Port (DTE)4 | RJ-45-to-RJ-45 Rollover Cable | RJ-45-to-DB-25 Terminal Adapter | Console Device | ||
|---|---|---|---|---|---|
| Signal | RJ-45 Pin | RJ-45 Pin | DB-25 Pin | Signal | |
| RTS | 15 | 8 | 5 | CTS | |
| DTR | 2 | 7 | 6 | DSR | |
| TxD | 3 | 6 | 3 | RxD | |
| GND | 4 | 5 | 7 | GND | |
| GND | 5 | 4 | 7 | GND | |
| RxD | 6 | 3 | 2 | TxD | |
| DSR | 7 | 2 | 20 | DTR | |
| CTS | 8 | 1 | 4 | RTS | |
4You can use the same cabling to connect a console to the auxiliary port.
5Pin 1 is connected internally to Pin 8.
Auxiliary Port Connection to a Modem
In order to connect a PC terminal to the router, use the RJ-45-to-RJ-45 roll-over cable and either the RJ-45-to-DB-25 female DTE adapter or the RJ-45-to-DB-9 female DTE adapter (labeled "TERMINAL"). This section lists the pinout descriptions for both DB-9 and DB-25 connections.
In order to connect a modem to the auxiliary port, use the RJ-45-to-RJ-45 rollover cable and the RJ-45-to-DB-25 male DCE adapter (labeled "MODEM").
Auxiliary Port Signaling and Cabling Using a DB-25 Adapter
Here is the pinout description for the modem connection:
| Auxiliary Port (DTE) | RJ-45-to-RJ-45 Rollover Cable | RJ-45-to-DB-25 Modem Adapter | Modem | ||
|---|---|---|---|---|---|
| Signal | RJ-45 Pin | RJ-45 Pin | DB-25 Pin | Signal | |
| RTS | 16 | 8 | 4 | RTS | |
| DTR | 2 | 7 | 20 | DTR | |
| TxD | 3 | 6 | 3 | TxD | |
| GND | 4 | 5 | 7 | GND | |
| GND | 5 | 4 | 7 | GND | |
| RxD | 6 | 3 | 2 | RxD | |
| DSR | 7 | 2 | 8 | DCD | |
| CTS | 8 | 1 | 5 | CTS | |
6Pin 1 is connected internally to Pin 8.
Alternative Terminal and Modem Connections
| Cisco Port Connection | RJ-45 Cable Type | Adapter |
|---|---|---|
| Console port to PC | Straight-through | DCE, DB-9 female |
| Console port to terminal | Straight-through | DCE, DB-25 female |
| Auxiliary port to modem | Rollover7 | DCE8, DB-25, male |
| - | Straight-through | DTE8, DB-25, male |
7An octal cable or RJ-45 breakout cable is equivalent to a rollover cable.
8Modify the DB-25 adapter by removing pin 6 and placing it into the pin 8 position.