# Clocking.HBus.ClockMode

Specifies the board's control of the H.100 clock.

For information about setting up CT bus clocking, and rules and restrictions for configuring CT bus clocking, refer to Configuring board clocking.

#### Syntax

Clocking.HBus.ClockMode = clockmode

#### Access

Read/Write

#### Type

String

#### Default

STANDALONE

#### Allowed values

MASTER_A | MASTER_B | SLAVE | STANDALONE

#### Example

Clocking.HBus.ClockMode = MASTER_A

#### Details

Valid entries for the keyword include:

Value | Description
--- | ---
MASTER_A | The board is used to drive the CT bus A clock based on the timing information derived from a clocking source.
MASTER_B | The board is used to drive the CT bus B clock based on the timing information derived from a clocking source.
SLAVE | The board acts as a clock slave, deriving its timing from the primary bus master. Note: Connections are allowed to the board's CT bus timeslots.
STANDALONE | The board references its timing signal from its own oscillator and does not drive any CT bus timing signal clocks. Note: Connections are not allowed to the board's CT bus timeslots in standalone mode.

For more information about standalone mode, refer to Default connections.

#### See also

Clocking.HBus.AutoFallBack, Clocking.HBus.ClockSource