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Configuring Serial Port Parameters for CTP Bundles (CTP Menu)

This topic describes how to configure port parameters for serial interfaces.

Before you begin:

  • Disable the bundle before you modify the bundle options.

To configure serial port parameters for CTP bundles using the CTP Menu:

  1. From the CTP Main Menu, select 1) Bundle Operations.
  2. Select 1) CTP.
  3. Select a bundle from the list.

    If you select an active bundle, you are prompted to disable the bundle before configuring it.

  4. Select 3) Port Config.
  5. Configure the options as described in Table 1.
Table 1: CTP Bundle Serial Port Parameter Settings in the CTP Menu
Field Function Your Action

Port descriptor text

Specifies a description for the port.

Enter a description of up to 64 alphanumeric characters. Do not use the following characters:

( ; ' " ) ]


Displays the menu used to configure the interface type, mode, and encoding.

Select 2) Interface.


Specifies the electrical standard used on the serial interface.

You can install the following optional daughter cards on a serial interface:

  • T1/E1 (CTP1000 and CTP2000 series)

  • 4WTO (CTP1000 and CTP2000 series)

  • IRIG-B (CTP2000 series only)

  • Multiservice Daughter Cards (CTP 2000 and CTP150 series)

Select one:

  • OFF—Do not set the interface type to OFF.

  • EIA-530

  • EIA-530A

  • RS-232

  • V.35

  • Optional Interface


Specifies that the interface is connected to a data communication equipment (DCE) device or to a data terminal equipment (DTE) device.

Select one:

  • DCE—The interface is connected to a DCE device.

  • DTE—The interface is connected to a DTE device.


Specifies the serial encoding method used on this bundle.

When you change the encoding method, the clocking configuration changes to the default configuration for the encoding method that you select.

Select one:

  • NRZ—Nonreturn to zero (NRZ) line encoding.

  • ISOCH—Isochronous encoding. Isochronous encoding does not provide or embed the clock in the data.

  • CDI—Conditioned diphase. Conditioned diphase encoding recovers and embeds the clock in the data signal. CDI encoding provides a speed of up to 4608 KBps.

  • TRANS—Transparent encoding. See Configuring Transparent Encoding for CTP Bundles (CTP Menu).

  • TDM—Additional data is interleaved with the port’s serial data. This option is used on TDM/TDC high-speed ports and is available only on even-numbered ports on a CTP 2000 serial module. See Configuring Bundle Pairs for TDM/TDC Operation (CTP Menu).

  • TRANS8—Extension of the TRANS encoding. Compared with TRANS encoding, which sends four signals in each direction, with TRANS8 encoding, bandwidth is doubled and eight signals can be sampled and transported. This allows signals to be sent from additional interfaces that were not supported in TRANS 4.

Enter Synthesized port rate (KHz)

Specifies the speed of the port. In networks without bandwidth constraints, we recommend a multiple of 10.

The port speed recommendations vary according to encoding type:

  • For transparent mode circuits, the port speed is the sample rate for user data. Therefore, the port rate should be a multiple of the user data rate.

  • For CDI circuits, the maximum port speed is limited to 4608 KBps.

The port speed also varies depending on hardware:

  • CTP2000 devices cannot have an aggregate port rate greater than 114.688 Mbps.

Enter a number from 0.00100 through 12880.00000 KHz.

Enable adaptive clocking?

Specifies whether adaptive clocking is enabled for this circuit.

If both end nodes are not locked to a clock reference, we recommend that you enable one end (not both) for adaptive clocking

Appears only if you select ISOCH, CDI, TRANS, or TDM encoding.

Specify y (yes) or n (no).

Initialize adaptive clocking parameters? y[n]: y

If you enabled adaptive clocking, specifies whether or not to initialize adaptive clocking parameters to their default values, which depend on port speed, packet size, and buffering parameters set on the bundle.

We recommend the following settings:

  • If you are configuring the bundle for adaptive clocking for the first time, enter y.

  • If you have previously configured the bundle to optimize adaptive clocking for this network, enter n.

Specify y (yes) or n (no).

TDC Clk/Data on port N+1

This option is used for TDM/TDC operation. See Configuring the High-Speed CTP Bundle for TDM/TDC Operation (CTP Menu).


TDM rates

This option is used for TDM/TDC operation. See Configuring the High-Speed CTP Bundle for TDM/TDC Operation (CTP Menu).