Linepattrn – Cirrus Logic EP93xx User Manual
Page 301
DS785UM1
8-37
Copyright 2007 Cirrus Logic
Graphics Accelerator
EP93xx User’s Guide
8
8
8
Bit Descriptions:
RSVD:
Reserved - Unknown during read
YINIT:
Y Initialization - Read/Write
The value in this field specifies a 12 bit binary fraction of a
pixel that provides sub-pixel precision to the algorithm.
The minimum fractional value is 1/4096. This field can also
be initialized to account for truncation errors in the drawing
algorithm.
XINIT:
X Initialization - Read/Write
The value in this field specifies a 12 bit binary fraction of a
pixel that provides sub-pixel precision to the algorithm.
The minimum fractional value is 1/4096. This field can also
be initialized to account for truncation errors in the drawing
algorithm.
LINEPATTRN
Address:
0x8004_003C - Read/Write
Default:
0x000F_FFFF
Mask:
0x000F_FFFF
Definition:
Line Pattern Register
Bit Descriptions:
RSVD:
Reserved - Unknown during read
CNT:
The value in this field specifies the pixel position in the
PATRN field that defines the end of the pattern. It is used
as the repeat interval for the pattern counter.
PATRN:
The bit values in this field specify an ‘on’ and ‘off’ pattern
that is to be used during a Line Draw function. The pattern
will repeat based on the CNT value.
A ‘1’ causes a pixel fill from the
register.
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
RSVD
CNT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PATRN