IBM RT Series Hardware Reference Manual page 348

TNL SN20-9844 (March 1987) to 75X0235
Rectangular Destination Only Graphic Operation Types
A rectangular region of pels (destination) is operated on by the graphic operation processor in
the bit map. The graphic operation either writes or read-modify-writes the destination specified.
The parameters specifying the rectangular destination are the coordinates of the lower right
corner point (X, Y exclusive) and the size (DX, DY) of the rectangular region.
Note: The microcode register ending conditions are defined for graphic operation types
X'2F','35','36','2C','2D', and '2E' only. All other graphic operation types have register ending
conditions which are not defined.
'--_ _ _ _ _ D_E_ST_I_N_A_TI_O_N _ _ _ _ _
---JI}-
DELTA Y
+
1
~
IDYl
(X,Y) LOWER RIGHT CORNER
I
(exclusive)
'--------~-------~
DELTA X
+
1
=
(OX)
Notes:
1. The DX
&
DY variables represent the actual number of pels written.
2. The X & Y variables are the right-bottom corner pel exclusive.
36 Extended Monochrome Graphics Adapter