What cad size commands do not change the zoom

Please predecessors to the students to find a CAD command, or applet, so that the 1:1 scaling graphics, or the size of the original size.

mark, set in what proportion of it.We have always been drawing units in the 1:1 draw, only to change the frame size, there is the advantage of no need for me to say.frame without Mark size, Why not frame and graphics to do??
In CAD, is in fact to do so, you should be able to feel the layout in this, no matter how much the plans, drawings always goes on Full display, and why is that?
Much said, Oh, I hope this idea to help you.