MB87P2020 Datasheet, PDF (167/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

Graphic Processing Unit
3.4 Supported Physical Color Space / Bit Stream Format
Combinations
Table 3-4 gives an overview on the legal physical color space / bits stream format combinations for the pri-
mary display. These are derived from the features of the supported displays. An analog output for S9…S12
is also possible in twin display mode (see next section).
Table 3-4: Supported combinations of physical color space to bit stream format
Physical color
Bit stream format code
space codes
S1 S2 S4 S6 S8 S9 S12 S18 S24 AN
1bpp
xxx
RGB111
xxx
4bpp
x
x
RGB333
x
RGB444
x
RGB666
x
RGB888
xx
3.5 Twin Display Mode
Twin Display Mode is only available for MB87P2020-A (Jasmine). MB87J2120 (Lavender) does not sup-
port this feature.
The GPU offers the opportunity to run a digital and an analog display in parallel (to output according data
at digital and analog output pins, respectively). This is referred to as twin display mode and may be used to
concurrently output the picture and post-processing it (e.g. do some color keying). The implication, how-
ever, is that both data streams use identical resolutions and sync timing. Some sync signals may not be avail-
able at the multipurpose pins as well (see 3.14.1). In twin display mode one display becomes the primary
display, the other the secondary display. The distinction which display is primary depends on the bit stream
format as shown in table 3-5.
Table 3-5: Primary / secondary display distinction in twin display mode
Bit stream format
AN
S9…S24
Others
Primary display
Analog
Digital
Digital
Secondary display
Digital
Analog
No twin display mode available.
When the analog display is secondary pixel data are auto scaled to 8 bit per color channel for DAC outputs
to maintain full voltage swing (bit with at the digital outputs remains according to selected bit stream for-
mat). This auto scaling works as explained for bit expansion in 2.3.
GPU Control Information
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