Hardware Cursor; Figure 7-8. Three And Four Count Axis; Table 7-9. Programming 33% Duty Cycle Into The Lookup Table - Cirrus Logic EP93 Series User Manual

Raster Engine With Analog/LCD Integrated Timing and Interface
EP93xx User's Guide
7
Assuming that the 3-bit input pattern that represents this 33% duty cycle grayscale is 0x2 or
010b, the values in
table. In this mode, the X locations are ignored by the grayscale generation.
Frame Vert
Ctr Ctr
D18 D17
0 0

7.4.9 Hardware Cursor

The raster engine provides support for a hardware cursor. The hardware cursor has a
separate bus mastering interface that allows it's image to be stored anywhere in memory.
Software provides a location start, reset, size, X and Y position, and two cursor colors. The
hardware loads a line at a time from memory and multiplexes the video stream data based on
the cursor values. The X and Y locations are compared to the horizontal and vertical counters
and trigger the state machine to enable the cursor output overlay.
7-24
Frame 0
V
E
R
T
Frame 2

Figure 7-8. Three and Four Count Axis

Table 7-9 are used to program this pattern into the grayscale look-up-

Table 7-9. Programming 33% Duty Cycle into the Lookup Table

1
Horz VCNT (lines)
1
HCNT 1
Ctr
(pixels) 1
D
Register
D16 1
address
5
0 base + 0x08 X
base + 0x28 X
base + 0x48 X
base + 0x68 X
Copyright 2007 Cirrus Logic
H O R Z Frame 1
1 0 0 0
0 0 1 1
0 1 0 0
0 0 1 1
1 0 0 1
1 0 0 0
1 1 1 1 1 1 1 0
1 1 1 0 0 0 0 1
1 0 0 1 1 0 0 1
0 1 0 1 0 1 0 1
D D D D D
D D D
1 1 1 1 1
9 8 7
4 3 2 1 0
X X X 0 0 1 0 1
X X X 1 1 0 0 0
X X X 0 0 0 1 1
X X X X X X X X
0 1 0 0
0 1 0 0
0 0 1 1
0 0 0 0 0 0 0 GrySclLUT
1 1 1 0 0 0 0 Address *4
1 0 0 1 1 0 0
Frame
0 1 0 1 0 1 0
D D D D D D D
6 5 4 3 2 1 0
1 0 0 0 0 0 1
0 1 0 0 0 1 0
0 0 1 1 1 0 0
X X X X X X X
Pixel
Value
00 010
01 010
10 010
11 010
DS785UM1