STV3550B STMicroelectronics, STV3550B Datasheet - Page 51

• Manufacturer Part Number: STV3550B
• Manufacturer: STMicroelectronics

Specifications of STV3550B

• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Compliant

STV3550
Figure 33. OSD CLUT programming flowchart
4.1.5
Palette with n Colors
Palettep[31:0]
Mixing OSD and video signals
The mixing function is used to blend each OSD pixel with the corresponding pixel
generated by the video planes behind the OSD. The mix weight is a programmable
parameter and can be set for each OSD region, or for each color. The mixing mode
bits (MiMo[1:0]) are used to select one of four possible mixing modes.
Table 14.
00
01
10
11
In this example, the 4th color of the palette (programmed in SDRAM) is loaded at the CLUTAdd[7:0]
address in the OSD CLUT (18th address of the OSD CLUT). Therefore, the 4th color of the palette
(pointed by Palettep[31:0]) is the first color to be loaded in the OSD CLUT.
Memory Space
Memory Space
256th Color
Mixing modes
2nd Color
4th Color
nth Color
1st Color
SDRAM
Header
32 bits
MiMo[1:0]
... Colors
NCL[7:0]
OSD
First Address
256th Address
Clutadd[7:0]
Pixel mixing mode
Global mixing mode
Proportional mixing mode
No mixing mode
= >@ 17
Graphics functional description
(NCL[7:0]+1) th Color
Description
OSD CLUT
4th Color
32 bits
n Colors
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