9 hardware cursor, 9 hardware cursor -24, Figure 7-8. three and four count axis -24 – Cirrus Logic EP93xx User Manual

Page 206: Figure 7-8

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7-24

DS785UM1

Copyright 2007 Cirrus Logic

Raster Engine With Analog/LCD Integrated Timing and Interface
EP93xx User’s Guide

7

7

7

Figure 7-8. Three and Four Count Axis

Assuming that the 3-bit input pattern that represents this 33% duty cycle grayscale is 0x2 or
010b, the values in

Table 7-9

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

table. In this mode, the X locations are ignored by the grayscale generation.

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.

Frame 0

H O R Z

Frame 1

V

1

0

0

0

0

1

0

0

E

0

0

1

1

0

1

0

0

R

0

1

0

0

0

0

1

1

T

Frame 2

0

0

1

1

1

0

0

1

1

0

0

0

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

Frame

Vert

Horz

VCNT (lines)

1
1

1
1

1
1

1
1

1
0

1
0

1
0

1
0

0
1

0
1

0
1

0
1

0
0

0
0

0
0

0
0

GrySclLUT
Address *4

Ctr

Ctr

Ctr

HCNT

(pixels)

1
1

1
0

0
1

0
0

1
1

1
0

0
1

0
0

1
1

1
0

0
1

0
0

1
1

1
0

0
1

0
0

Frame

Pixel

D18

D17

D16

Register

address

D
1
5

D
1
4

D
1
3

D
1
2

D
1
1

D
1
0

D
9

D
8

D
7

D
6

D
5

D
4

D
3

D
2

D
1

D
0

Value

0

0

0

base + 0x08

X

X

X

X

0

0

1

0

1

1

0

0

0

0

0

1

00

010

base + 0x28

X

X

X

X

1

1

0

0

0

0

1

0

0

0

1

0

01

010

base + 0x48

X

X

X

X

0

0

0

1

1

0

0

1

1

1

0

0

10

010

base + 0x68

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

11

010

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