Base Unit Description

The base unit is a unique stack unit that can be selected by the Unit Select switch on the front-panel of the 400-ST1 cascade module. One unit in the stack configuration must be assigned as the base unit; all other units in the stack must have their Unit Select switch set to Off (see “ Unit Select Switch” on page 5). Any single unit in the stack can be assigned as the base unit.

The physical ordering of all of the other units in the stack are determined by the position of the base unit within the stack. This is important for management applications that view the physical ordering of the units within the stack.

Some characteristics of the base unit are:

•Initial installation --- during the initial installation of the stack, the software automatically determines the physical order of all units in the stack according to the position of the base unit within the stack.

For example, when the stack is powered up, the base unit becomes unit 1 and the unit that the base unit connects to (via the Cascade A Out cable) becomes unit 2 (and the next unit is unit 3 and so on), until the maximum stack configuration (up to 8 units) is reached.

If the base unit is changed to another unit in the stack, the new base unit keeps its original unit number in the stack.