Here is what the HELP-file says about "isometric projections":
This command projects a selection into its isometric top view, front view or side view.
After starting the tool, the CAD toolbar shows the selection tools. Use them to select the entities you want to project.
Click the right arrow button in the CAD toolbar to continue.
Set the reference point with the mouse or enter a coordinate in the command line.
Choose the side of the projection in the options toolbar and enter a segment length. The segment length is used for arcs and circles which are broken up into line segments in the projection.
Set the target point of the projection
I shall be grateful for any help in understanding the subject.