> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/tdm.md).

# TDM and lines parameters

E1/T1/J1 lines, timeslots, framing and clocking. 31 parameters.

## A

| Parameter            | Description                                                                                                                                                            |
| -------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Auto Switch-back** | Automatically switch media (trunks, VOIP) back to the original unit when it becomes available, otherwise the backup unit remains active until it is manually rebooted. |

## C

| Parameter                  | Description                                                                                                                                                                          |
| -------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **Clock Ref Type**         | Line Service: Use a line service as the clock source BITS Port: Use the BITS port line interface as the clock source SONET SDH: Use the SONET SDH line interface as the clock source |
| **Clock Reference Source** | The Clock Reference Source parameter defines which object is to be used as an external clocking source.                                                                              |
| **Clock Reference Type**   | The Clock Reference Type parameter defines which type of object is to be used as an external clocking source.                                                                        |
| **Commadn-line arguments** | Command-line arguments to pass to the application when it is launched.                                                                                                               |

## E

| Parameter    | Description                                                                    |
| ------------ | ------------------------------------------------------------------------------ |
| **Encoding** | The Encoding parameter is used to set an encoding scheme for a line interface. |

## F

| Parameter   | Description                                                             |
| ----------- | ----------------------------------------------------------------------- |
| **Framing** | The Framing parameter is used to set a framing type for a line service. |

## I

| Parameter     | Description                                                                           |
| ------------- | ------------------------------------------------------------------------------------- |
| **Idle code** | The byte pattern transmitted on the timeslot when there is no established connection. |

## L

| Parameter        | Description                                                                                                    |
| ---------------- | -------------------------------------------------------------------------------------------------------------- |
| **Length**       | The Length parameter is used to indicate the physical length of a line.                                        |
| **Line Service** | The Line Service parameter indicates which TDM line service is to be associated with the object being created. |
| **Local Index**  | The Local Index parameter assigns an integer to represent an object.                                           |
| **Loop time**    | When enabled, the clock signal received on this trunk is the one that is used to transmit.                     |
| **Loopback**     | The Loopback parameter is used to set the loopback state of a line service.                                    |

## Q

| Parameter                  | Description                                                                             |
| -------------------------- | --------------------------------------------------------------------------------------- |
| **Qualify Delay**          | Minimal period of time required to qualify a clock source.                              |
| **Qualify Recovery Delay** | Minimal period of time required to qualify a clock source for automatic clock recovery. |

## S

| Parameter                                           | Description                                                                   |
| --------------------------------------------------- | ----------------------------------------------------------------------------- |
| **Signal Level**                                    | The signal level of the TDM intefrace can be adjusted from a value of 0 to 7. |
| **SS7: Send LPA when Continuity Check is Required** | During COT process, send LPA when TDM loopback is ready.                      |

## T

| Parameter                                | Description                                                                                  |
| ---------------------------------------- | -------------------------------------------------------------------------------------------- |
| **TDM Volume Control: RX Gain Level**    | Audio level gain from TDM (to IP)                                                            |
| **TDM Volume Control: TX Gain Level**    | Audio level gain toward TDM (from IP)                                                        |
| **Trunk CVC anomalies (qualify mark)**   | CVC anomalies counter limit (per qualify period) to qualify a clock.                         |
| **Trunk CVC anomalies (unqualify mark)** | CVC anomalies counter limit (per qualify period) to unqualify a clock source for recovery.   |
| **Trunk FEC anomalies (qualify mark)**   | FEC anomalies counter limit (per qualify period) to qualify a clock source for recovery.     |
| **Trunk FEC anomalies (unqualify mark)** | FEC anomalies counter limit (per qualify period) to unqualify a clock source for recovery.   |
| **Trunk LOS defects (qualify mark)**     | LOS defects counter limit (per qualify period) to qualify a clock source.                    |
| **Trunk LOS defects (unqualify mark)**   | LOS defects counter limit (per qualify period) to unqualify a clock source.                  |
| **Trunk OOF defects (qualify mark)**     | OOF defects counter limit (per qualify period) to qualify a clock source.                    |
| **Trunk OOF defects (unqualify mark)**   | OOF defects counter limit (per qualify period) to unqualify a clock source.                  |
| **Type**                                 | The Type parameter takes on different meanings depending on the context in which it is used. |

## U

| Parameter                             | Description                                                                                                 |
| ------------------------------------- | ----------------------------------------------------------------------------------------------------------- |
| **Use Clock Ref Recovery**            | Enable/disable clock switching to a higher priority clock source that is qualified for recovery.            |
| **Use TMS Link Switch Over Recovery** | Enable/disable automatic switchover from secondary to primary TMS unit as soon as the primary unit is ready |

## V

| Parameter          | Description                                                                           |
| ------------------ | ------------------------------------------------------------------------------------- |
| **Variant Script** | The Variant Script parameter is used to set a regional script for a CAS R2 signaling. |


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