SDA6000 Datasheet, PDF (299/380 Pages) Infineon Technologies AG – Teletext Decoder with Embedded 16-bit Controller

SDA 6000
Display Generator
The different formats of pixels stored in a frame buffer which are used by the SRU are
described in the following paragraphs:
Frame Buffer in 2-bit Pixel Format
Using this format, the frame buffer contains colour vectors. These 2-bitplane colour
vectors will be converted into 4:4:4:2 format (R:G:B: transparency value) by addressing
vector 252 … 255 of CLUT2.
10 10 10 10
Pixel0 Pixel1 Pixel2 Pixel3
76543210
UED11179
Figure 10-10 2-bit Pixel Format for Use in Frame Buffer
Frame Buffer in 8-bit Pixel Format
Using this format, the frame buffer contains colour vectors. These 8-bitplane colour
vectors will be converted into 4:4:4:2 format (R:G:B: transparency value) by CLUT2.
Pixel (7...0)
76543210
UED11180
Figure 10-11 8-bit Pixel Format for Use in Frame Buffer
Frame Buffer in 16-bit Pixel Format (4:4:4:2 or TTX)
This 16-bit format supports an RGB mode (4:4:4:2) and a TTX mode. Which of these
modes is in use can be decided pixel by pixel with bit ‘M’:
• TTX format (M = ‘0’)
• 12-bitplanes RGB (4:4:4:2) format (M = ‘1’) with 2 transparency bits TR(1 … 0).
Note: The meaning of transparency bits is described in more detail in Chapter 10.3.1
and Chapter 10.3.2.
Users Manual
10 - 14
2000-06-15