Cisco Catalyst 2810 Series User manual

Connecting a Terminal to the
Console Port on Catalyst Switches
Document ID: 10600
Contents
Introduction
Before You Begin
Conventions
Prerequisites
Identifying a Rollover Cable, Straight-through, and Crossover Cable
Connecting a Terminal to Catalyst 1900/2820, 2900/3500XL, 2940, 2950, 2970, 3550,
and 3750 Series Switches
Connecting to a Terminal
Connecting a Terminal to Catalyst 2948G-L3, 4908G-L3, and 4840G Series Switches
Console Port Pinouts
Connecting a Terminal to Catalyst 2926 and 2926G Series Switches
Catalyst 2926G Series Switch
Connecting a Terminal to the Catalyst 5000 Supervisor Engine I and II Console Port
Configuring a Terminal for Attachment to the Console Port
Connecting a Terminal to the Catalyst 5000 Supervisor Engine III Console Port
Configuring a Terminal for Attachment to the Console Port
Connecting a Terminal to the Catalyst 5000 Supervisor Engine II G and III G Console
and RSFC Ports
Console Port Mode Switch
Configuring a Terminal for Attachment to the Console or RSFC Port
Connecting a Terminal to the Catalyst 4000 Supervisor Engine I Console Port
Connecting a Terminal to the Catalyst 4000/4500 Supervisor Engine II/II+/III/IV,
2948G, 2980G, and 4912G
Catalyst 6000/6500 Supervisor Engine I, II and 720 Console Port Signals and Pinouts
Console Port Mode Switch
Console Port Mode 1 Signaling and Pinouts
Console Port Mode 2 Signaling and Pinouts
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (1 of 19) [9/4/2003 12:36:02 PM]

Catalyst 8510CSR, and 8540CSR Switches Console Port Pinouts
Related Information
Introduction
This document focuses on using the default parameters for connecting and configuring management
terminals. The switches covered in this document are the Catalyst 1900, 2820, 2900, 3500, 2940, 2950,
2970, 3550, 2948G-L3, 4000/4500, 4840G, 4908G-L3, 5000/5500, 6000/6500, and 8500 series switches.
For more information on using different connection speeds, cables, or devices, see the Hardware and
Installation Guide for your Catalyst series switch.
Before You Begin
Conventions
For more information on document conventions, see the Cisco Technical Tips Conventions.
Prerequisites
There are no specific prerequisites for this document.
Identifying a Rollover Cable, Straight-through, and Crossover Cable
The information in this document is based on the software and hardware versions below.
The Catalyst series switches mentioned in this document require the use of either a rollover or
straight-through RJ-45 cable to connect a terminal to the console port depending on the type of
supervisor and other factors. Rollover cables and straight through cables have different pinouts than
crossover cables, which can be used to connect 10/100 base TX ethernet ports together between switches.
To identify the type of cable you are using, refer to RJ-45 Cables or Cabling Guide for Console and AUX
Ports.
The information presented in this document was created from devices in a specific lab environment. All
of the devices used in this document started with a cleared (default) configuration. If you are working in
a live network, ensure that you understand the potential impact of any command before using it.
Connecting a Terminal to Catalyst 1900/2820,
2900/3500XL, 2940, 2950, 2970, 3550, and 3750
Series Switches
Use the supplied rollover cable and the DB-9 adapter to connect a PC to the switch console port. You
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (2 of 19) [9/4/2003 12:36:02 PM]

need to provide an RJ-45-to-DB-25 female data terminal equipment (DTE) adapter if you want to
connect the switch console port to a terminal. You may order a kit (part number ACS-DSBUASYN=)
containing the adapter from Cisco. The PC or terminal must support VT100 terminal emulation. The
terminal emulation softwarefrequently a PC application such as Hyperterminal or Procomm Plusmakes
communication between the switch and your PC or terminal possible during the setup program.
Follow these steps to connect the PC or terminal to the switch:
Be sure that your PC or terminal emulation software is configured to communicate with the switch
via hardware flow control.
1.
Configure the baud rate and character format of the PC or terminal to match these console port
default characteristics:
9600 baud
❍
8 data bits❍
1 stop bit❍
No parity❍
2.
Using the supplied rollover cable, insert the RJ-45 connector into the console port.
3.
Attach the supplied RJ-45-to-DB-9 female DTE adapter to a PC, or attach an appropriate adapter
to the terminal.
4.
Insert the other end of the supplied rollover cable in the attached adapter.5.
Run the terminal emulation program if you are using a PC or a terminal.6.
Table A-1: Console Port Signaling and Cabling Using a DB-9 Adapter
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 1 8 8 CTS
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (3 of 19) [9/4/2003 12:36:02 PM]

Not
Connected 2 7 6 DSR
TxD 3 6 2 RxD
GND 4 5 5 GND
GND 5 4 5 GND
RxD 6 3 3 TxD
Not
Connected 7 2 4 DTR
CTS 8 1 7 RTS
Connecting to a Terminal
Use the thin, flat RJ-45-to-RJ-45 rollover cable and RJ-45-to-DB-25 female DTE adapter to connect the
console port to a terminal. Table A-2 lists the pinouts for the console port, the RJ-45-to-RJ-45 rollover
cable, and the RJ-45-to-DB-25 female DTE adapter.
Note: The RJ-45-to-DB-25 female DTE adapter is not supplied with the switch. You may order a kit
(part number ACS-DSBUASYN=) containing this adapter from Cisco.
Table A-2: Console Port Signaling and Cabling Using a DB-25 Adapter
Console
Port
(DTE)
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 1 8 5 CTS
Not
Connected 2 7 6 DSR
TxD 3 6 3 RxD
GND 4 5 7 GND
GND 5 4 7 GND
RxD 6 3 2 TxD
Not
Connected 7 2 20 DTR
CTS 8 1 4 RTS
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (4 of 19) [9/4/2003 12:36:02 PM]

Connecting a Terminal to Catalyst 2948G-L3,
4908G-L3, and 4840G Series Switches
You may configure the Catalyst switch routers from a direct console connection to the console port or
remotely through its management port.
Use the RJ-45-to-RJ-45 rollover cable and RJ-45-to-DB-9 female data terminal equipment (DTE)
adapter (labeled "Terminal") to connect the console port to a PC running terminal emulation
software.
●
If you are using a direct console connection, configure your terminal emulation program for 9600
baud, 8 data bits, no parity, and 1 stop bit.
●
Console Port Pinouts
The console port is an RJ-45 receptacle. Data Terminal Ready (DTR) and Data Set Ready (DSR)
handshake signals are supported. The Request To Send (RTS) signal tracks the state of the Clear To Send
(CTS) signal. Table B-1 lists pinouts for the console port.
Table B-1: Console Port Pinouts
Pin Signal Direction Description
1¹ RTS/CTS Output Request To Send / Clear To
Send
2 DTR Output Data Terminal Ready
3 TxD Output Transmit Eata
4 SGND  Signal Ground
5 SGND  Signal Ground
6 RxD Input Receive Data
7 DSR Input Data Set Ready
8¹ RTS/CTS Input Request To Send / Clear To
Send
¹Pin 1 and pin 8 are connected.
Connecting a Terminal to Catalyst 2926 and 2926G
Series Switches
On the Catalyst 2926 series switch, the console port is located on the Supervisor Engine front panel and
is labeled "CONSOLE," as shown in the figure below.
Figure: Console Port Connector (Catalyst 2926 Series Switch)
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (5 of 19) [9/4/2003 12:36:02 PM]

The Supervisor Engine console port is a data communications equipment (DCE) DB-25 receptacle that
supports a DCE EIA/TIA-232 interface. EIA/TIA-232 supports unbalanced circuits at signal speeds up to
64 kbps.
Before connecting the console port, check the terminal documentation to determine the baud rate. The
baud rate of the terminal must match the default baud rate (9600 bps) of the switch console port. Set up
the terminal as follows:
9600 BPS
●
8 data bits●
No parity●
1 stop bit●
Use a straight-through cable to connect the switch to a data terminal equipment (DTE) device, such as a
terminal or a PC. Use a null-modem cable to connect the switch to a remote DCE device, such as a
modem or a Data Service Unit (DSU). See the figure below for DCE and DTE cable connectors.
Figure: EIA/TIA-232 Adapter Cable Connectors, Network End
Note: The console port is an asynchronous (Async) serial port; any device connected to this port must be
capable of asynchronous transmission.
Both Data Set Ready (DSR) and Data Carrier Detect (DCD) are active when the system is running. The
Request To Send (RTS) signal tracks the state of the Clear To Send (CTS) input. The console port does
not support modem control or hardware flow control. Table C-1 lists the console port pinouts.
Table C-1: Catalyst 2926 Series Console Port Pinouts
Pin Signal Direction Description
1 GND Ground
2 RxD > Receive Data
3 TxD < Transmit Data
4 CTS < Clear To Send
5 RTS > Return To Send
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (6 of 19) [9/4/2003 12:36:02 PM]

7 GND Ground
8 DTR > Data Terminal Ready
20 DCD < Data Carrier Detect
Catalyst 2926G Series Switch
The console and auxiliary (AUX) ports, located on the front panel of the Catalyst 2926G series switch,
are shown in the figure below.
Note: The AUX port is currently not supported.
Figure: Console and AUX Port Connectors
The console port, which is an EIA/TIA-232 asynchronous serial port with an RJ-45 connector, is a
full-featured DTE connection with hardware flow control.
Connect the terminal using a thin, flat RJ-45-to-RJ-45 rollover cable and an RJ-45-to-DB-9, an
RJ-45-to-D-subminiature female, or an RJ-45-to-D-subminiature male adapter (depending on the
terminal connector).
Table C-2: Catalyst 2926G Series Console Port Pinouts
Console Port Console Device
Pin (signal) Connect to
1 is looped to pin 8 n/a
2 (DTR) DSR
3 (RxD) TxD
4 (GND) GND
5 (GND) GND
6 (TxD) RxD
7 (DSR) DTR
8 is looped to pin 1 n/a
Note: An RJ-45-to-RJ-45 rollover cable and the adapters are provided in the console port accessories kit
shipped with your Catalyst 2926G series switch.
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (7 of 19) [9/4/2003 12:36:03 PM]

Connecting a Terminal to the Catalyst 5000
Supervisor Engine I and II Console Port
The port is located on the Supervisor Engine front panel and is labeled "CONSOLE," as shown above.
The console port is a data communications equipment (DCE) DB-25 male receptacle that supports a
DCE EIA/TIA-232 interface. Both Data Set Ready (DSR) and Data Carrier Detect (DCD) are active
when the system is running. The Request To Send (RTS) signal tracks the state of the Clear To Send
(CTS) input. The console port does not support modem control or hardware flow control.
Note: If you need a replacement console port accessory kit for your Supervisor Engine I or II, the part
number is ACS-2500ASYN=. This is the same kit that ships with many other Cisco routers, including the
Cisco 2500 series.
Use a null-modem cable to connect the switch to a remote DCE device, such as a modem. For more
information on accessing a Supervisor Engine I remotely, see Connecting a Modem to the Console Port
on Catalyst Switches. Use a straight-through cable to connect the switch to a data terminal equipment
(DTE) device, such as a terminal or PC.
Figure: EIA/TIA-232 DB25 Adapter Cable Connectors
Table D-1: Supervisor Engine I & II Console Cable Pinouts 25 PIN Straight Through Cable
Switch Console (DCE) Terminal (DTE)
2 Rxd 2 TxD
3 Txd 3 RxD
4 RTS 4 RTS
5 CTS 5 CTS
6 DSR 6 DSR
7 GND 7 GND
8 DCD 8 DCD
20 DTR 20 DTR
Table D-2: Supervisor Engine I & II Console Cable Pinouts 25 PIN - 9 PIN Adaptor Cable
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (8 of 19) [9/4/2003 12:36:03 PM]

Switch Console (DCE) Terminal (DTE)
2 Rxd 3 TxD
3 Txd 2 RxD
4 RTS 7 RTS
5 CTS 8 CTS
6 DSR 6 DSR
7 GND 5 GND
8 DCD 1 DCD
20 DTR 4 DTR
Configuring a Terminal for Attachment to the Console Port
Note: The console port is an asynchronous serial port; any device connected to this port must be capable
of asynchronous transmission.
Before connecting the console port, check the terminal documentation to determine the baud rate. The
baud rate of the terminal must match the default baud rate (9600 baud) of the console port. Set up the
terminal as follows:
9600 baud
●
8 data bits●
No parity●
1 stop bit●
Connecting a Terminal to the Catalyst 5000
Supervisor Engine III Console Port
The port is located on the Supervisor Engine front panel and is labeled "CONSOLE," as shown above.
The port is an EIA/TIA-232 asynchronous, serial, full-featured data terminal equipment (DTE)
connection with hardware flow control and an RJ-45 connector. Use a straight-through cable to connect
the switch to a Data Terminal Equipment (DTE) device, such as a terminal or PC.
Note: If you need a replacement console port accessory kit for your Supervisor Engine III, the part
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (9 of 19) [9/4/2003 12:36:03 PM]

number is CAB-S3-CONSOLE=.
Note: The auxiliary (AUX) port is not supported.
Figure: EIA/TIA-232 RJ-45 Adapter Cable Connector
Table E-1: Supervisor Engine III Console Port Pinouts RJ45-to-DB25 Adaptor Cable
RJ45 on Switch Console
(DTE) (Uses straight through
cable.) DB25 on Terminal (DTE)
1 RTS (looped to pin 8) 
2 DTR 6 DSR
3 RxD 2 TxD
4 GND 7 GND
5 GND tied to 4 7 GND
6 TxD 3 RxD
7 DSR 20 DTR
8 CTS (looped to pin 1) 
Table E-2: Supervisor Engine III Console Port Pinouts RJ45-to-DB9 Adaptor Cable
RJ45 on Switch Console (DTE)
(Uses straight through cable.) DB9 on Terminal (DTE)
1 RTS (looped to pin 8) 
2 DTR 6 DSR
3 RxD 3 TxD
4 GND 5 GND
5 GND tied to 4 5 GND
6 TxD 2 RxD
7 DSR 4 DTR
8 CTS (looped to pin 1) 
Configuring a Terminal for Attachment to the Console Port
Note: The console port is an asynchronous (Async) serial port; any device connected to this port must be
capable of asynchronous transmission.
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (10 of 19) [9/4/2003 12:36:03 PM]

Before connecting the console port, check the terminal documentation to determine the baud rate. The
baud rate of the terminal must match the default baud rate (9600 baud) of the console port. Set up the
terminal as follows:
9600 baud
●
8 data bits●
No parity●
1 stop bit●
Connecting a Terminal to the Catalyst 5000
Supervisor Engine II G and III G Console and RSFC
Ports
The switch console port and the RSFC console port are located on the Supervisor Engine front panel and
are labeled "CONSOLE" and "RSFC" respectively, as shown above. Both ports are EIA/TIA-232
asynchronous, serial, full-featured data terminal equipment (DTE) connections with hardware flow
control and RJ-45 connectors.
Note: If you need a replacement console port accessory kit for your Supervisor Engine IIG or IIIG, the
part number is ACS-2500ASYN=. This is the same kit that ships with many other Cisco routers,
including the Cisco 2500 series.
The type of cable used to connect to a SupIIG or IIIG console port depends on the position of the console
port mode switch. Please refer to Console Port Mode Switch for more information.
For more information on accessing a Supervisor Engine IIG or IIIG remotely, see Connecting a Modem
to the Console Port on Catalyst Switches.
Use a null-modem cable to connect the switch to a remote data communications equipment (DCE)
device, such as a modem. For more information on accessing an Supervisor Engine IIG or IIIG remotely,
see Connecting a Modem to the Console Port on Catalyst Switches. Use a straight-through cable to
connect the switch to a DTE device, such as a terminal or a PC.
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (11 of 19) [9/4/2003 12:36:03 PM]

Console Port Mode Switch
The console port mode switch allows you to connect either a terminal (DTE) or a modem (DCE)
depending on the mode that is selected and the cable that you are using.
Note: The cable and adapters shipped with the Supervisor Module II G and Supervisor Module III G are
the same ones used on the Cisco 2500 series routers (and other Cisco products).
Use the console port mode switch as follows:
Mode 1: Press to the in position. Use this mode to connect a terminal to the port using the console
cable and DTE adapter (labeled "Terminal") that shipped with the Supervisor Engine. You may
also use this mode to connect a modem to the port using the console cable and the DCE adapter
(labeled "Modem") that shipped with the switch.
●
Mode 2: Depress to the out position. Use this mode to connect a terminal to the port using the
Supervisor Engine III console cable (not provided).
●
Figure: EIA/TIA-232 RJ-45 Adapter Cable Connector
Table F-1: Console Port Signaling and Cabling Using a DB9 Adapter
Switch
Console
(DTE)
RJ45-RJ45
Rollover Cable RJ45-to-DB9
Adapter Terminal (DTE)
Signal RJ45
Pin RJ45 Pin DB9 Pin Signal
RTS 1¹ 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 8¹ 1 7 RTS
¹Pin 1 is connected internally to Pin 8.
Table F-2: Console Port Signaling and Cabling Using a DB25 Adapter
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (12 of 19) [9/4/2003 12:36:03 PM]

Switch
Console
(DTE)
RJ45-to-RJ45
Rollover Cable RJ45-to-DB25 Adapter Terminal (DTE)
Signal RJ45
Pin RJ45 Pin DB25 Pin Signal
RTS 1¹ 8 5 CTS
DTR 2 7 6 DSR
TxD 3 6 3 RxD
GND 4 5 7 GND
GND 5 4 7 GND
TxD 6 3 2 TxD
DSR 7 2 20 DTR
CTS 8¹ 1 4 RTS
¹Pin 1 is connected internally to Pin 8.
Configuring a Terminal for Attachment to the Console or RSFC Port
Note: The console port is an asynchronous (Async) serial port; any device connected to this port must be
capable of asynchronous transmission.
Before connecting the console port, check the terminal documentation to determine the baud rate. The
baud rate of the terminal must match the default baud rate (9600 baud) of the console port. Set up the
terminal as follows:
9600 baud
●
8 data bits●
No parity●
1 stop bit●
Connecting a Terminal to the Catalyst 4000
Supervisor Engine I Console Port
The console port, shown in the figure below, is a data communications equipment (DCE) DB-25
receptacle that supports a DCE EIA/TIA-232 interface. EIA/TIA-232 supports unbalanced circuits at
signal speeds up to 64 kbps.
Figure: DCE DB-25 Connector
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (13 of 19) [9/4/2003 12:36:03 PM]

Use a null-modem cable to connect the switch to a remote DCE device, such as a modem or a Data
Service Unit (DSU). Use a straight-through cable to connect the switch to a data terminal equipment
(DTE) device, such as a terminal or a PC.
The console port of the Catalyst 4000 Supervisor Engine I uses a DB-25 connector and supports Data
Terminal Ready (DTR), Data Set Ready (DSR), Clear To Send (CTS), and Request To Send (RTS)
handshake signals. Table G-1 lists the Catalyst 4000 Supervisor Engine I console port pinouts.
Table G-1: Catalyst 4003 Console Port Pinouts
Pin Signal Direction Description
1 Ground
2 RxD Input Receive Data
3 TxD Output Transmit Data
4 CTS Input Clear To Send
5 RTS Output Request To Send
7 Ground
8 DTR Output Data Terminal
20 DSR Input Data Set Ready
Connecting a Terminal to the Catalyst 4000/4500
Supervisor Engine II/II+/III/IV, 2948G, 2980G, and
4912G
You may configure the Catalyst 4000/4500 series switches from a direct console connection to the
console port.
Use the RJ-45-to-RJ-45 rollover cable and RJ-45-to-DB-9 female data terminal equipment (DTE)
adapter (labeled "Terminal") to connect the console port to a PC running terminal emulation
software. If you are using a direct console connection, configure your terminal emulation program
for 9600 baud, 8 data bits, no parity, and 1 stop bit.
●
Table H-1 lists the switch console port pinouts. Use a straight-through cable to connect the switch to a
DTE device, such as a terminal or a PC.
Table H-1: Catalyst 4000/4500 Supervisor II and higher, 2948G, 2980G, and 4912G Console Port
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (14 of 19) [9/4/2003 12:36:03 PM]

Pinouts
Pin Signal Direction Description
1 RTS Output Request To Send
2 DTR Output Data Terminal Ready
3 TXD Output Transmit Data
4 Ground
5 Ground
6 RXD Input Receive Data
7 DSR Input Data Set Ready
8 CTS Input Clear To Send
Catalyst 6000/6500 Supervisor Engine I, II and 720
Console Port Signals and Pinouts
The Catalyst 6000/6500 family switch comes with an accessory kit that contains the cable and adapters
you need to connect a console (an ASCII terminal or a PC running terminal emulation software) or
modem to the console port. The accessory kit includes these items:
RJ-45-to-RJ-45 rollover cable
●
RJ-45-to-DB-9 female DTE adapter (labeled "Terminal")●
RJ-45-to-DB-25 female DTE adapter (labeled "Terminal")●
RJ-45-to-DB-25 male DCE adapter (labeled "Modem")●
These are the same cable and adapters that ship with the Cisco 2500 series routers and other Cisco
products.
Console Port Mode Switch
The Supervisor Engine front-panel console port mode switch allows you to connect a terminal or modem
to the console port as follows:
Note: Use a ball-point pen tip or other small, pointed object to access the console port mode switch. The
switch is shipped in the in position.
Mode 1: Switch is in the in position. Use this mode to connect a terminal to the console port using
the RJ-45-to-RJ-45 rollover cable and the data terminal equipment (DTE) adapter (labeled
"Terminal"). You may also use this mode to connect a modem to the console port using the
RJ-45-to-RJ-45 rollover cable and the data communications equipment (DCE) adapter (labeled
"Modem"). See Console Port Mode 1 Signaling and Pinouts.
●
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (15 of 19) [9/4/2003 12:36:03 PM]

Mode 2: Switch is in the out position. Use this mode to connect a terminal to the console port
using the Catalyst 5000 family Supervisor Engine III console straight-through cable and an
appropriate adapter for the terminal connection (cable and adapter are not provided). See Console
Port Mode 2 Signaling and Pinouts.
●
Console Port Mode 1 Signaling and Pinouts
This section provides the signaling and pinouts for the console port in mode 1 (port mode switch in the in
position).
DB-9 Adapter (for Connecting to a PC)
Use the RJ-45-to-RJ-45 rollover cable and the RJ-45-to-DB-9 female DTE adapter (labeled
"Terminal") to connect the console port to a PC running terminal emulation software. Table I-1
lists the pinouts for the asynchronous serial console port, the RJ-45-to-RJ-45 rollover cable, and
the RJ-45-to-DB-9 female DTE adapter.
Table I-1: Port Mode 1: Console Port Signaling and Pinouts (DB-9 Adapter)
Console
Port 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 1¹ 8 8 CTS
DTR 2 7 6 DSR
TxD 3 6 2 RxD
GND 4 5 5 GND
GND 5 4 5 GND
GND 6 3 3 TxD
DSR 7 2 4 DTR
CTS 8¹ 1 7 RTS
¹Pin 1 is connected internally to Pin 8.
●
DB-25 Adapter (for Connecting to a Terminal)
Use the RJ-45-to-RJ-45 rollover cable and the RJ-45-to-DB-25 female DTE adapter (labeled
"Terminal") to connect the console port to a terminal. Table I-2 lists the pinouts for the
asynchronous serial console port, the RJ-45-to-RJ-45 rollover cable, and the RJ-45-to-DB-25
female DTE adapter.
Table I-2: Port Mode 1: Console Port Signaling and Pinouts (DB-25 Adapter)
●
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (16 of 19) [9/4/2003 12:36:03 PM]

Console
Port 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 1¹ 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 8¹ 1 4 RTS
¹Pin 1 is connected internally to Pin 8.
Modem Adapter
Use the RJ-45-to-RJ-45 rollover cable and the RJ-45-to-DB-25 male DCE adapter (labeled
"Modem") to connect the console port to a modem. Table I-3 lists the pinouts for the asynchronous
serial auxiliary port, the RJ-45-to-RJ-45 rollover cable, and the RJ-45-to-DB-25 male DCE
adapter.
Table I-3: Port Mode 1: Console Port Signaling and Pinouts (Modem Adapter)
Console
Port 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 1¹ 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 8¹ 1 5 CTS
¹Pin 1 is connected internally to Pin 8.
●
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (17 of 19) [9/4/2003 12:36:03 PM]

Console Port Mode 2 Signaling and Pinouts
This section provides the signaling and pinouts for the console port in mode 2 (port mode switch in the
"out" position). See Table I-4 for the pinouts. Mode 2 gives you the option of using a standard RJ-45
straight-through cable to connect a terminal.
Table I-4: Console Port Pinouts (Port Mode Switch Out)
Console Port Console Device
Pin (signal) Input/Output
1 (RTS)¹ Output
2 (DTR) Output
3 (RxD) Input
4 (GND) GND
5 (GND) GND
6 (TxD) Output
7 (DSR) Input
8 (CTS)¹ Input
¹Pin 1 is connected internally to Pin 8.
Catalyst 8510CSR, and 8540CSR Switches Console
Port Pinouts
The console port on the route processor is an EIA/TIA-232, data communications equipment (DCE),
DB-25 receptacle. Both Data Set Ready (DSR) and Data Carrier Detect (DCD) are active when the
system is running. The Request To Send (RTS) signal tracks the state of the Clear To Send (CTS) input.
The console port does not support modem control or hardware flow control. The console port requires a
straight-through EIA/TIA-232 cable. Table J-1 lists the console port pinouts.
Table J-1: DB-25 Console Port Pinouts
Pin Signal Direction Description
1 GND  Ground
2 TxD < Transmit Data
3 RxD > Receive Data
4 RTS > Ready To Send¹
5 CTS > Clear To Send¹
6 DSR > Data Set Ready (always on)²
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (18 of 19) [9/4/2003 12:36:03 PM]

7 GND  Ground
8 DCD > Data Carrier Detect (always on)²
20 DTR < Data Terminal Ready
Shield GND  Shield Ground
¹Pins 4 and 5 are connected.
²Pins 6 and 8 are connected.
Related Information
Connecting a Modem to the Console Port on Catalyst Switches●
Technical Support - Cisco Systems●
All contents are Copyright © 1992-2003 Cisco Systems, Inc. All rights reserved. Important Notices and Privacy Statement.
Updated: Sep 04, 2003 Document ID: 10600
Cisco - Connecting a Terminal to the Console Port on Catalyst Switches
http://www.cisco.com/warp/public/473/9.html (19 of 19) [9/4/2003 12:36:03 PM]