NAME   rev ADDR type chip Description
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DIWSTRT 08E  W  A D   Display window start (upper left vert-hor pos)
DIWSTOP 090  W  A D   Display window stop (lower right vert-hor pos)
	These registers control the display window size and position,
	by locating the upper left and lower right corners.

	BIT# 15  14  13  12  11  10  09  08  07  06  05  04  03  02  01  00
	USE  V7  V6  V5  V4  V3  V2  V1  V0  H9  H8  H7  H6  H5  H4  H3  H2

	DIWSTRT is vertically restricted to the upper 2/3
	of the display (v8=0),and horizontally restricted to the
	left 3/4 of the display (H8=0).*
	* Poof.. (see DIWHIGH for exceptions)