TDM Bus and Clock Timing Parameters

The TDM Bus parameters are described in the table below.

TDM Bus and Clock Timing Parameters

Parameter

Description

TDM Bus Parameters

Digital PCM

'PCM Law Select'

configure voip > media tdm > pcm-law-select

[PCMLawSelect]

Defines the type of pulse-code modulation (PCM) companding algorithm law in input and output TDM bus.

■ [1] Alaw
■ [3] MuLaw

The default value is automatically selected according to the Protocol Type of the selected trunk (E1 defaults to A-Law; T1 defaults to Mu-Law). If the Protocol Type is set to NONE, the default is MuLaw.

Note:

■ For the parameter to take effect, a device restart is required.
■ Typically, A-Law is used for E1 spans; Mu-Law for T1/J1 spans.
■ Typically, A-Law is used for most BRI variants.

'Idle PCM Pattern'

configure voip > media tdm > idle-pcm-pattern

[IdlePCMPattern]

Defines the PCM Pattern that is applied to the PSTN timeslot (B-channel) when the channel is idle.

The range is 0 to 255. The default is set internally according to the Law select 1 (0xFF for Mu-Law; 0x55 for A-law).

Note: For the parameter to take effect, a device restart is required.

'Idle ABCD Pattern'

configure voip > media tdm > idle-abcd-pattern

[IdleABCDPattern]

Defines the ABCD (CAS) Pattern that is applied to the CAS signaling bus when the channel is idle.

The valid range is 0x0 to 0xF. The default is -1 (i.e., default pattern is 0000).

Note:

■ For the parameter to take effect, a device restart is required.
■ The parameter is applicable only when using PSTN interface with the RAW_CAS protocol.

General

'TDM Bus Clock Source'

configure voip > media tdm > tdm-bus-clock-source

[TDMBusClockSource]

Defines the clock source to which the device synchronizes.

■ [1] Internal = (Default) Generate clock from local source.
■ [4] Network = Recover clock from PSTN line.

Note:

■ For the parameter to take effect, a device restart is required.

'TDM Bus Local Reference'

configure voip > media tdm > pstn-bus-local-reference

[TDMBusPSTNLocalReference]

Defines the physical Trunk ID from which the device recovers (receives) its clock synchronization.

The range is 1 to the maximum number of Trunks. The default is 1.

Note: The parameter is applicable only if the [TDMBusClockSource] parameter is configured to 4 and the [TDMBusPSTNAutoClockEnable] parameter to 0.

'TDM Bus PSTN Auto FallBack Clock'

configure voip > media tdm > pstn-bus-auto-clock

[TDMBusPSTNAutoClockEnable]

Enables the PSTN trunk Auto-Fallback Clock feature.

■ [0] Check box cleared o = (Default) Disabled. Recovers the clock from the trunk line configured by the [TDMBusPSTNLocalReference] parameter.
■ [1] Check box selected þ = Enabled. Recovers the clock from any connected synchronized slave trunk line. If this trunk loses its synchronization, the device attempts to recover the clock from the next trunk. Note that initially, the device attempts to recover the clock from the trunk defined by the [TDMBusPSTNLocalReference] parameter.

Note:

■ For the parameter to take effect, a device restart is required.
■ The parameter is applicable only if the [TDMBusClockSource] parameter is configured to 4.

'TDM Bus PSTN Auto Clock Reverting'

configure voip > media tdm > pstn-bus-auto-clock-reverting

[TDMBusPSTNAutoClockRevertingEnable]

Enables the PSTN trunk Auto-Fallback Reverting feature. If enabled and a trunk returning to service has an AutoClockTrunkPriority parameter value that is higher than the priority of the local reference trunk (configured by the [TDMBusPSTNLocalReference] parameter), the local reference reverts to the trunk with the higher priority that has returned to service for the device's clock source.

■ [0] Check box cleared o = (Default) Disabled.
■ [1] Check box selected þ = Enabled.

Note:

■ For the parameter to take effect, a device restart is required.
■ The parameter is applicable only when the [TDMBusPSTNAutoClockEnable] parameter is set to 1.