The Text Orientation tab of the Dimensions dialog box sets the orientation of the dimension units in relation to the dimension line.
Select Aligned Face Up to force dimension units to display so that the base of the text is oriented along the dimension line, but the text is always upright in relation to the line.
Select Towards Object to force dimension units to display so that the base of the text is oriented along the dimension line. For a horizontal dimension line in which the extensions are below the line, the dimension units are displayed upside down.
Select Horizontal to force the dimension units to display horizontally, even for vertical and aligned dimension lines.
Select Horizontal/Vertical to force the dimension units to display horizontally for horizontal and aligned lines, and vertically for vertical lines.
Select Custom Angle to display dimension units at a specific angle. To set the custom angle, you can either drag the red needle in the dial control or click in the Angle text box and enter a specific value.