unction with the following drawings, in which:FIG. 1 illustrates a notebook computer for docking to an expansion base unit;FIG. 2 is a block diagram of the notebook computer of FIG. 1;FIGS. 3A and 3B are a block diagram of the expansion base unit of FIG. 1;FIG. 4 is a block diagram of portions of the notebook computer and expansion base unit for control of docking and undocking operations;FIG. 5 i