Z90251 Datasheet, PDF (40/97 Pages) Zilog, Inc. – eZVision 200 Television Controllers with OSD

Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
32
Bit/
Field
Bit
Position R/W Value Description
Halftone Effect Output 7
Delay on P20
R/W xx/x Bits 5, 4 in ROW_SPACE/ bit 7
00/0 No Delay
00/1 Delay by 0.5 Dot-Clock Period
01/0 Delay by 1.0 Dot-Clock Period
01/1 Delay by 1.5 Dot-Clock Period
10/0 Delay by 2.0 Dot-Clock Period
10/1 Delay by 2.5 Dot-Clock Period
11/0 Delay by 3.0 Dot-Clock Period
11/1 Delay by 3.5 Dot-Clock Period
Mesh Color
6, 5, 4 R/W
Defines the mesh color.
B,G,R respectively.
P20 for
Halftoning
3
R/W 0 Normal Mesh effect
1 Use P20 Output for Halftoning
Software Field Number/ 2
Polarity of Halftone
Effect Output
R/W 0 Even Field/Positive Halftone Effect
Output
1 Odd Field/Negative Halftone Effect
Output
Software Mesh
1
R/W 0 Hardware Defines Field Number
1 Software Defined Field Number
Mesh Enable
0
R/W 0 Mesh is Disabled
1 Mesh is Enabled
When working with Progressive mode, mesh does not work the
same way as in Interlace mode.
Bit 7, Halftone Output Delay on P20, is the amount of time that output of the
halftone signal is delayed to compensate for the amount of delay of OSD RGB
from external circuitries.
Bits 6, 5, and 4, Mesh Color, define the color of the mesh window. The colors are
specified in Blue, Green, Red order, as shown in Table 17.
PS001301-0800