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Clocking.HBus.FallBackClockSource

Clocking.HBus.FallBackClockSource = clock_source
Note: For more information about setting up CT bus clocking, and about the rules and restrictions that apply to setting up clocking with CG 6000C boards, refer to Section 3.5.

Value	Description
`OSC`	Causes the board to drive the T1 or E1 line transmit clock using the on-board oscillator. This setting should only be used when the board's T1 or E1 connection is isolated from the telephone network. This would apply, for example, if you use a T1 or E1 connection as a link between the two computers, or if you use one board to simulate network traffic to another. The on-board oscillator is accurate to 32 ppm (parts per million) and meets the requirements for a Stratum 4E clock.
`A_CLOCK`	Specifies to use `CT_C8_A` and `CT_FRAME_A` timing signals bus as the board's fallback timing reference.
`B_CLOCK`	Specifies to use the `NETREF2CT_C8_B` and `CT_FRAME_B` timing signals as the board's fallback timing reference.
`NETREF`	Specifies to use `NETREF` as the board's fallback timing reference. The NETREF reference source is set with Clocking.HBus.NetRefSource (the source may be a trunk on another board).
`NETREF2`	Specifies to use `NETREF2` as the board's fallback timing reference. The NetRef2 reference source is set with Clocking.HBus.NetRef2Source (the source may be a trunk on another board).
Network	Specifies that the board uses a digital trunk as the board's fallback timing reference (this trunk is specified with the Clocking.HBus.ClockSourceNetwork keyword). Note: CG 6000C boards operating in slave mode cannot fallback to `Network 1`.