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ClockRef

Syntax

ClockRef = MVIP | H100 | OSC | NET1 | NET2 | NET3 | NET4 |SEC8K

Description

This statement configures the telephony bus clock. The allowed values for ClockRef are: Value Definition MVIP Causes the board to act as a clock slave to the MVIP-90 bus by deriving the local clock from the bus. Another board must drive the clock on the MVIP-90 bus. Note: Typically should not be used on an H.100 board except in a mixed H.100 and MVIP-90 system where an MC1 board is the bus clock master. H100 Causes the board to act as a clock slave to the H.100 bus by deriving the local clock from the bus. Note: For CompactPCI AG boards, causes the board to act as a clock slave to the H.110 bus. Another H.100 board (or H.110 board) must drive the clock on the bus. OSC For the AG-T1, AG-E1, AG Quad, AG 4000, or CompactPCI AG Quad boards, drives the T1 or E1 line transmit clock using the on-board oscillator. Derives the local clock and telephony bus clock using the extracted clock from the T1/E1 line. For the AG-8 board, uses the on-board oscillator as a reference. Setting ClockRef to OSC for a board makes that board the telephony bus clock master. If the clock master is an H.100 board, it will drive both the H.100 and MVIP-90 bus clocks. ClockRef should be set to MVIP or H100 for all other boards on the bus. Do not use for boards that are connected to the PSTN or to any other system that provides reference clocking to the AG board and its telephony bus. Note: AG board on-board oscillators are not of stratum 4 frequency, accuracy and stability. Using OSC will likely create clock slips against the PSTN on the AG board's transmit side. Use NETx to make an AG board to act as a slave to the PSTN, and drive the board's transmit clock in sync with the received clock. For back-to-back operation with two T1 or E1 AG boards on different MVIP buses, set ClockRef to OSC on one board, and ClockRef to Net1 on the other. NET1, NET2, NET3, NET4 AG-T1, AG-E1, AG Quad, AG 4000, and CompactPCI AG Quad boards only. Causes the board to derive the local clock, telephony bus clock, and line transmit clock using the clock extracted from the specified T1 or E1 trunk. If no clock signal is detected, the board defaults to the OSC option. Setting ClockRef to NETx for a board makes the board the clock master. If the clock master is an H.100 board, it will drive both the H.100 bus clocks and the MVIP-90 bus clocks. ClockRef should be set to MVIP or H100 for all other boards on the bus. SEC8K Derives the local clock from the telephony bus backup reference clock (Sec8k or CT_NETREF). Setting ClockRef to SEC8K for a board makes the board the clock master. ClockRef should be set to MVIP or H100 for all other boards on the bus.
The ClockRef statement is mandatory for AG-24/30/48/60 boards and for any configuration where the following statements are present in the AG configuration file: EnableMVIP DriveSec8K (for all boards except AG-24/30/48/60) MVIPslot Caution: If the bus clock master board is an AG board, it must be assigned to the first board-specific section in the AG configuration file (Board 0). Therefore, if the clock master is an AG board, it must be board 0. The bus clock master must be initialized before the bus clock slaves. You cannot initialize a clock slave board until a bus clock signal has been provided by initializing the clock master board.
The default ClockRef value for the AG-8 is OSC; for the AG-T1, AG-E1, AG Quad, AG 4000, and CompactPCI AG Quad the default is NET1. For the AG-24/30/48/60, the default (and only valid value) is MVIP. Note: The ClockRef = OSC option on AG-T1, AG-E1, AG Quad, AG 4000, and CompactPCI AG Quad boards should be used only when the T1 or E1 connection is isolated from the public network. This would apply, for example, when a T1 link is used as a link between two adjacent computers, or one T1 board is used to simulate network traffic to another. Two T1 boards connected back-to-back for testing should not be on the same telephony bus unless a third board is providing the bus clock. The hardware is designed so that if the T1 or E1 board is clock master to a telephony bus, the bus clock is always derived from the T1 or E1 line, even if ClockRef = OSC is specified.

Value	Definition
`MVIP`	Causes the board to act as a clock slave to the MVIP-90 bus by deriving the local clock from the bus. Another board must drive the clock on the MVIP-90 bus. Note: Typically should not be used on an H.100 board except in a mixed H.100 and MVIP-90 system where an MC1 board is the bus clock master.
H100	Causes the board to act as a clock slave to the H.100 bus by deriving the local clock from the bus. Note: For CompactPCI AG boards, causes the board to act as a clock slave to the H.110 bus. Another H.100 board (or H.110 board) must drive the clock on the bus.
`OSC`	For the AG-T1, AG-E1, AG Quad, AG 4000, or CompactPCI AG Quad boards, drives the T1 or E1 line transmit clock using the on-board oscillator. Derives the local clock and telephony bus clock using the extracted clock from the T1/E1 line. For the AG-8 board, uses the on-board oscillator as a reference. Setting `ClockRef` to `OSC` for a board makes that board the telephony bus clock master. If the clock master is an H.100 board, it will drive both the H.100 and MVIP-90 bus clocks. `ClockRef` should be set to `MVIP` or `H100` for all other boards on the bus. Do not use for boards that are connected to the PSTN or to any other system that provides reference clocking to the AG board and its telephony bus. Note: AG board on-board oscillators are not of stratum 4 frequency, accuracy and stability. Using `OSC` will likely create clock slips against the PSTN on the AG board's transmit side. Use `NET`x to make an AG board to act as a slave to the PSTN, and drive the board's transmit clock in sync with the received clock. For back-to-back operation with two T1 or E1 AG boards on different MVIP buses, set `ClockRef` to `OSC` on one board, and `ClockRef` to `Net1` on the other.
`NET1`, `NET2`, `NET3`, `NET4`	AG-T1, AG-E1, AG Quad, AG 4000, and CompactPCI AG Quad boards only. Causes the board to derive the local clock, telephony bus clock, and line transmit clock using the clock extracted from the specified T1 or E1 trunk. If no clock signal is detected, the board defaults to the `OSC` option. Setting `ClockRef` to `NET`x for a board makes the board the clock master. If the clock master is an H.100 board, it will drive both the H.100 bus clocks and the MVIP-90 bus clocks. `ClockRef` should be set to `MVIP` or `H100` for all other boards on the bus.
`SEC8K`	Derives the local clock from the telephony bus backup reference clock (Sec8k or CT_NETREF). Setting `ClockRef` to `SEC8K` for a board makes the board the clock master. `ClockRef` should be set to `MVIP` or `H100` for all other boards on the bus.

Caution:	If the bus clock master board is an AG board, it must be assigned to the first board-specific section in the AG configuration file (`Board 0`). Therefore, if the clock master is an AG board, it must be board 0. The bus clock master must be initialized before the bus clock slaves. You cannot initialize a clock slave board until a bus clock signal has been provided by initializing the clock master board.

Example

ClockRef = MVIP

ClockRef

Syntax

Description

Example

See Also