Downloads |
Table Of Contents
Synchronous and Asynchronous Mode Configurations
Platform Support for the NM-16A/S Feature
Configuring the Slow-Speed Interfaces for NM-16A/S
Configuring the ignore Command for NM-16A/S
Configuration Examples for NM-16A/S
NM-16A/S
The NM-16A/S is a slow-speed, high-density serial network module (NM) offering asynchronous and synchronous interfaces and flexible port configuration. The NM-16A/S offers:
•
Synchronous interfaces that support a data rate of up to 128 kbps
•
•
Feature History for NM-16A/S
12.2(15)ZJ
This feature was introduced.
12.3(2)T
This feature was integrated into Cisco IOS Release 12.3(2)T.
Finding Support Information for Platforms and Cisco IOS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.
Contents
•
•
Prerequisites for NM-16A/S
This feature requires Cisco IOS Release 12.2(15)ZJ or Release 12.3(2)T or a later release.
Restrictions for NM-16A/S
The NM-16A/S is factory configurable and not field upgradable.
Information About NM-16A/S
To configure the NM-16A/S feature, you must understand the following concept.
•
•
Synchronous and Asynchronous Mode Configurations
The synchronous ports are addressed as interface serial slot/port. The asynchronous port, when configured, utilizes the tty line numbering scheme, which is linear and allows for 32 tty ports per network module slot. Table 1 shows the port number corresponding to tty line number.
Platform Support for the NM-16A/S Feature
This feature is supported on Cisco 2610XM, Cisco 2611XM, Cisco 2620XM, Cisco 2621XM, Cisco 2650XM, Cisco 2651XM, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, and Cisco 3745 routers.
This feature is not supported on the non-XM models of the Cisco 2610, Cisco 2611, Cisco 2620, Cisco 2621, Cisco 2650, Cisco 2651. This feature is not supported on the Cisco 3620, Cisco 3640, and Cisco 3640/A routers.
How to Configure the NM-16A/S
This section contains the following procedures:
•
•
Configuring the Slow-Speed Interfaces for NM-16A/S
To specify the mode of a slow-speed serial interface on a router as either synchronous or asynchronous, use the following commands:
SUMMARY COMMANDS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
DETAILED COMMANDS
Configuring the ignore Command for NM-16A/S
Perform this task to configure the serial interface to ignore the specified signals as the line up/down indicator:
SUMMARY STEPS
1.
2.
3.
4.
or
ignore [dtr | local-loopback | rts]
or
ignore [cts | dsr]
or
ignore [cts | dcd | dsr]5.
DETAILED STEPS
What to Do Next
To verify that the slow-speed serial interface is configured correctly, enter the show interfaces serial privileged EXEC command to display the command settings for the router.
To enable the transition of the serial control leads to be reported on the console, use the debug serial lead-transition command in privileged EXEC mode.
Caution
The following is sample output from the debug serial lead-transition command:
Router# debug serial lead-transitionRouter# debug condition interface serial 1/1*Mar 1 00:17:15.040:slot(1) Port(1):DSR/DTR is Deasserted*Mar 1 00:17:15.040:slot(1) Port(1):CTS/RTS is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):DCD/Local Loop is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):DSR/DTR is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):CTS/RTS is DeassertedRouter# no shut down serial 1/1*Mar 1 00:16:52.298:slot(1) Port(1):DSR/DTR is Asserted*Mar 1 00:16:52.298:slot(1) Port(1):CTS/RTS is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):DCD/Local Loop is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):DSR/DTR is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):CTS/RTS is AssertedConfiguration Examples for NM-16A/S
The following is sample output from the show running-config command:
show running-config Example
interface Serial1/0ip address 10.1.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/1ip address 10.2.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/2ip address 10.3.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/3ip address 10.4.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/4ip address 10.5.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/5ip address 10.6.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/6ip address 10.7.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/7ip address 10.8.0.2 255.255.255.0load-interval 30no keepaliveclockrate 128000fair-queueno cdp enable!interface Serial1/8physical-layer asyncip address 10.9.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/9physical-layer asyncip address 10.10.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/10physical-layer asyncip address 10.11.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/11physical-layer asyncip address 10.12.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/12physical-layer asyncip address 10.13.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/13physical-layer asyncip address 10.14.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/14physical-layer asyncip address 10.15.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicatedfair-queue 64 16 0!interface Serial1/15physical-layer asyncip address 10.16.0.2 255.255.255.0encapsulation pppload-interval 60async mode dedicated!endAdditional References
The following sections provide references related to NM-16A/S.
Related Documents
MIBs
RFCs
Technical Assistance
Command Reference
This section documents modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.3 T command reference publications.
clock rate
To configure the clock rate for the hardware connections on serial interfaces such as network interface modules (NIMs) and interface processors to an acceptable bit rate, use the clock rate command in interface configuration mode. To remove the clock rate if you change the interface from a DCE to a DTE device, use the no form of this command.
clock rate {speed | line rate}
no clock rate
Syntax Description
Defaults
No clock rate is configured.
Command Modes
Interface configuration
Command History
Usage Guidelines
Using the no form of this command on a DCE interface sets the clock rate to the hardware-dependent default value.
Cable Length
Be aware that the fastest speeds might not work if your cable is too long, and that speeds faster than 148000 bps are too fast for EIA/TIA-232 signaling. We recommend that you use only the synchronous serial EIA/TIA-232 signal at speeds up to 64000 bps. To permit a faster speed, use EIA/TIA-449 or V.35.
Synchronous Serial Port Adapters
For the synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7200 series routers, and on second-generation Versatile Interface Processors (VIP2s) in Cisco 7500 series routers, the clock rate you enter is rounded (if needed) to the nearest value that your hardware can support. To display the clock rate value for the port adapter, use the more system:running-config command.
If you plan to netboot your router over a synchronous serial port adapter interface and have a boot image prior to Cisco IOS Release 11.1(9)CA that does not support nonstandard (rounded) clock rates for the port adapters, you must use one of the following standard clock rates: 1200, 2400, 4800, 9600, 19200, 38400, 56000, 64000
Examples
The following example sets the clock rate on the first serial interface to 64000 bps:
Router(config)# interface serial 0Router(config-if)# clock rate 64000The following example sets the clock rate on a synchronous serial port adapter in slot 5, port 0 to 1234567. In this example, the clock rate is adjusted to 1151526 bps.
Router(config)# interface serial 5/0Router(config-if)# clock rate 1234567%Clockrate rounded to nearest value that your hardware can support.%Use Exec Command 'more system:running-config' to see the value rounded to.The following example configures serial interface 5/0 with a clock rate that is rounded to the nearest value that is supported by the hardware:
Router# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# interface serial 5/0Router(config-if)# clock rate 1234567%Clockrate rounded to nearest value that your hardware can support.%Use Exec Command 'more system:running-config' to see the value rounded to.Router(config-if)# exitThe following example shows how to determine the exact clock rate that the serial interface was rounded to using the more system:running-config command. This example shows only the relevant information displayed by the more system:running-config command; other information was omitted.
Router# more system:running-configBuilding configuration......interface Serial5/0no ip addressclockrate 1151526!debug serial lead-transition
To activate the leads status transition debug capability for all capable ports, use the debug serial lead-transition command in privileged EXEC mode. To disable debugging output, use the no form of this command.
debug serial lead-transition
no debug serial lead-transition
Syntax Description
This command has no arguments or keywords.
Defaults
Debugging is not turned on.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
To control which port is to be reported and therefore reduce the risk of flooding the console screen with debug information, enter the debug condition interface serial slot/port command after using the debug serial lead-transition command to set the condition.
Caution
Examples
The following example shows the serial control leads reported for slot 1, port 1:
Router# debug serial lead-transitionRouter# debug condition interface serial 1/1*Mar 1 00:17:15.040:slot(1) Port(1):DSR/DTR is Deasserted*Mar 1 00:17:15.040:slot(1) Port(1):CTS/RTS is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):DCD/Local Loop is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):DSR/DTR is Deasserted*Mar 1 00:17:47.955:slot(1) Port(1):CTS/RTS is DeassertedRouter# no shut down serial 1/1*Mar 1 00:16:52.298:slot(1) Port(1):DSR/DTR is Asserted*Mar 1 00:16:52.298:slot(1) Port(1):CTS/RTS is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):DCD/Local Loop is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):DSR/DTR is Asserted*Mar 1 00:16:31.648:slot(1) Port(1):CTS/RTS is Asserted
Table 2 describes the significant fields shown in the output.
Related Commands
debug condition interface serial
Enables conditional debugging on a serial interface.
ignore (interface)
To configure the serial interface to ignore the specified serial signals as the line up/down indicator, use the ignore command in interface configuration mode. To restore the default, use the no form of this command.
DCE Asynchronous Mode
ignore [dtr | rts]
no ignore [dtr | rts]
DCE Synchronous Mode
ignore [dtr | local-loopback | rts]
no ignore [dtr | local-loopback | rts]
DTE Asynchronous Mode
ignore [cts | dsr]
no ignore [cts | dsr]
DTE Synchronous Mode
ignore [cts | dcd | dsr]
no ignore [cts | dcd | dsr]
Syntax Description
Defaults
The no form of this command is the default. The serial interface monitors the serial signal as the line up/down indicator.
Command Modes
Interface configuration
Command History
Usage Guidelines
Serial Interfaces in DTE Mode
When the serial interface is operating in DTE mode, it monitors the dcd signal as the line up/down indicator. By default, the attached DCE device sends the dcd signal. When the DTE interface detects the dcd signal, it changes the state of the interface to up.
SDLC Multidrop Environments
In some configurations, such as an SDLC multidrop environment, the DCE device sends the Data set ready (dsr) signal instead of the dcd signal, which prevents the interface from coming up. Use this command to tell the interface to monitor the dsr signal instead of the dcd signal as the line up/down indicator.
Examples
The following example configures serial interface 0 to ignore the dcd signal as the line up/down indicator:
interface serial 0ignore dcdRelated Commands
debug serial lead-transition
Activates the leads status transition debug capability for all capable ports.
show interfaces serial
Displays information about a serial interface.
Glossary
ATM—asynchronous transfer mode.
cts—clear to send. Circuit in the EIA/TIA-232 specification that is activated when DCE is ready to accept data from a DTE.
DCE—data circuit-terminating equipment (ITU-T expansion). Devices and connections of a communications network that comprise the network end of the user-to-network interface. The DCE provides a physical connection to the network, forwards traffic, and provides a clocking signal used to synchronize data transmission between DCE and DTE devices. Modems and interface cards are examples of DCE. Compare with DTE.
dcd—data carrier detect. DCD is a signal from the DCE device that typically means that the DCE is ready to accept data. If the DCE device is a modem, the DCD signal traditionally refers to the modem having received a modulation carrier signal and is now able to pass data.
DDR—dial-on-demand routing.
dsr—data set ready. EIA/TIA-232 interface circuit that is activated when DCE is powered up and ready for use.
DTE—data terminal equipment. Device at the user end of a user-to-network interface that serves as a data source, destination, or both. DTE connects to a data network through a DCE device (for example, a modem) and typically uses clocking signals generated by the DCE. DTE includes such devices as computers, protocol translators, and multiplexers. Compare with DCE.
dtr—data terminal ready. EIA/TIA-232 circuit that is activated to let the DCE know when the DTE is ready to send and receive data.
HDLC—High-Level Data Link Control.
ISL—Inter-Switch Link.
LAPB—Link Access Procedure, Balanced.
NIM—network interface module.
PPP—Point-to-Point Protocol.
rts—request to send. EIA/TIA-232 control signal that requests a data transmission on a communications line.
SLIP—Serial Line Internet Protocol.
SMDS—Switched Multimegabit Data Services.
VIP—Versatile Interface Processor.
Note
Copyright © 2003 Cisco Systems, Inc. All rights reserved.
