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Selecting the Type of Clocking on Serial Ports for CTP Bundles (CTP Menu)

 

This topic describes how to select the type of clocking that you want to use on serial ports. The type of clocking supported depends on the type of encoding you are using.

Before you begin:

  • Disable the bundle before you modify the bundle options.

CTP Menu gives you the option of selecting the clocking type when you change the interface encoding for a circuit. You can also specify the clocking type for CTP bundles using the CTP Menu as follows:

  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. Select 3) Clock Config.
  6. Select 1) Port Clock Config.
  7. Configure the options as described in Table 1.

Table 1: Clocking Type Supported for Each Encoding Type as Displayed in the CTP Menu

Encoding TypeClocking Type Supported

NRZ and TDM with interface mode set to DCE

You can specify the following clocking methods for NRZ and TDM circuits with DCE mode specified:

  • Custom—The custom clocking configuration is used.

  • Configured Rate, w/o Ext Tx Clk (TT)—Configured rate without external TX clock (TT). The CTP device synthesizes the rate that is used on the ST and RT outputs to the attached device. The ST is used to sample Send Data from the attached DTE. The clock is created by the CTP DDS circuitry and logic. This option is commonly used on circuits that are less than 1 Mbps.

  • Configured Rate, Ext Tx Clk (TT—Configured rate with external TX clock (TT). The CTP device synthesizes the rate that is used on the ST and RT outputs to the attached device. The clock is created by the DDS circuitry and logic. This option is used to sample Send Data from the attached device. It assumes that the attached device is using ST or clock reference that is traceable to CTP reference. It is typically used for higher data rates (>1 Mbps) and long cables.

  • All Clocked by Ext Tx Clk (TT)—All clocked with external TX clock (TT). The CTP device uses the external TT timing from the DTE for all clocking. Ext TT is used to sample Send Data from the attached device, to generate the RT clock, and to clock data into the IP network.

  • Adaptive Rate, Ext Tx Clk (TT)—Adaptive clocking with external TX clock (TT).

  • Adaptive Rate, w/o Ext Tx Clk (TT)—Adaptive clocking with internal clock.

  • Autobaud Rate, Ext Tx Clk (TT)—Autobaud rate with internal clock.

  • Autobaud Rate, w/o Ext Tx Clk (TT)—Autobaud rate with external clock.

  • TDM/TDC Interleaved Slow Port—Available only on odd-numbered ports. Use this option for the low-speed port of a time domain correlation (TDC) circuit.

NRZ and TDM with interface mode set to DTE

You can specify the following clocking methods for NRZ and TDM circuits with DTE mode specified:

  • Adaptive Rate, Ext Tx Clk (TT)—Adaptive clocking with external TX clock (TT).

  • Adaptive Rate, w/o Ext Tx Clk (TT)—Adaptive clocking with internal clock.

  • Autobaud Rate, Ext Tx Clk (TT)—Autobaud rate with internal clock.

  • Autobaud Rate, w/o Ext Tx Clk (TT)—Autobaud rate with external clock.

  • DTE, All Clocked by Ext Clk (ST/RT)—The DCE equipment provides all clocks. The ST input clock is used to clock out the external transmit clock (TT) and the send data (SD). The RT input clock is used to clock in the receive data (RD).

  • TDM/TDC Interleaved Slow Port—Available only on even-numbered bundles. Use this option for the slower port of the time domain correlation (TDC) circuit.

  • DTE, All Clocked by User Clk(RT)—The DCE equipment provides all clocks. The RT input clock is used to clock out the external transmit clock (TT) and the send data (SD) and to clock in the receive data (RD).

  • Custom—The custom clocking configuration is used.

ISOCH

You can specify the following clocking methods for ISOCH circuits:

  • Adaptive Rate, Ext Tx Clk (TT)—Adaptive clocking with external TX clock (TT).

  • Adaptive Rate, w/o Ext Tx Clk (TT)—Adaptive clocking with internal clock.

  • Autobaud Rate, Ext Tx Clk (TT)—Autobaud rate with internal clock.

  • Autobaud Rate, w/o Ext Tx Clk (TT)—Autobaud rate with external clock.

  • ISOCH - Master End—This end of the circuit generates a clock signal and sends it to the remote end. Configure ISOCH - Adaptive End at the remote end.

  • ISOCH - Adaptive End—This end of the circuit uses adaptive clocking to receive the clock signal from the remote end. The clock slave uses its period to determine when to sample data and how to transmit data across the link.

  • Custom—The custom clocking configuration is used.

CDI

You can specify the following clocking methods for CDI circuits:

  • Adaptive Rate, Ext Tx Clk (TT)—Adaptive clocking with external TX clock (TT).

  • Adaptive Rate, w/o Ext Tx Clk (TT)—Adaptive clocking with internal clock.

  • Autobaud Rate, Ext Tx Clk (TT)—Autobaud rate with internal clock.

  • Autobaud Rate, w/o Ext Tx Clk (TT)—Autobaud rate with external clock.

  • CDI - Master End—This end of the circuit generates a clock signal and sends it to the remote end. Configure CDI - Adaptive End at the remote end.

  • CDI - Adaptive End—This end of the circuit uses adaptive clocking to receive the clock signal from the remote end. The clock slave uses its period to determine when to sample data and how to transmit data across the link.

  • Custom—The custom clocking configuration is used.

TRANS

You can specify the following clocking methods for TRANS circuits:

  • Adaptive Rate, Ext Tx Clk (TT)—Adaptive clocking with external TX clock (TT).

  • Adaptive Rate, w/o Ext Tx Clk (TT)—Adaptive clocking with internal clock.

  • Autobaud Rate, Ext Tx Clk (TT)—Autobaud rate with internal clock.

  • Autobaud Rate, w/o Ext Tx Clk (TT)—Autobaud rate with external clock.

  • TRANS - Master End—This end of the circuit generates a clock signal and sends it to the remote end. Configure TRANS - Adaptive End at the remote end.

  • TRANS - Adaptive End—This end of the circuit uses adaptive clocking to receive the clock signal from the remote end. The clock slave uses its period to determine when to sample data and how to transmit data across the link.

  • Custom—The custom clocking configuration is used.