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TMS320DM6446
Digital Media System on-Chip
SPRS283–DECEMBER 2005
Simultaneous display of two video windows and two OSD windows (VIDWIN0/VIDWIN1 and
OSDWIN0/OSDWIN1).
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Separate enable for each window
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Programmable width, height, and base starting coordinates for each window
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External memory address and offset registers for each window
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Support for x2 and x4 zoom in both the horizontal and vertical direction
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OSDWIN1 can be used as an attribute window for OSDWIN0
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Attribute window blinking intervals
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Field/frame mode for the windows (interlaced/progressive)
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Eight step blending process between the OSD and video windows
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Transparency support for the OSD and video data (when a bitmap pixel is zero, there will be no
blending for that corresponding video pixel)
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Resize from VGA to NTSC/PAL (640x480 to 720x576) for both the OSD and video windows
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Reads in YCbCr data in 422 format from external memory, with the capability for swapping the
order of the CbCr component in the 32-bit word (this is relevant to the two video windows)
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Support for a ping-pong buffer scheme that can be used for VIDWIN0 (allows for video data to be
accessed from two different locations in DDR2)
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Each OSD window (either one, but not both at the same time) is capable of reading in RGB data
(16-bit data with six bits for the green and five bits each for the red and blue colors) instead of
bitmap data in YCbCr format restricted to a maximum of 8-bits
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The OSD bitmap data width is selectable between 1, 2, 4, or 8-bits.
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Each OSD window supports 16 entries for the bitmap (to index into a 256 entry RAM/ROM CLUT
table).
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Indirect support for 24-bit RGB input data (which will be transformed into 16-bit YCbCr video
window data) via the wrapper interface in the VPBE.
Support for a rectangular cursor window and a programmable background color selection.
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Programmable color palette with the ability to select between a RAM/ROM table with support for
256 colors.
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The width, height, and color of the cursor is programmable.
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The display priority is: Rectangular-Cursor > OSDWIN1 > OSDWIN0 > VIDWIN1 > VIDWIN0 >
background color
Support for attenuation of the YCbCr values for the REC601 standard.
The following restrictions exist in the OSD module.
Both the OSD windows and VIDWIN1 should be fully contained inside VIDWIN0.
When one of the OSD windows is set in RGB mode, it cannot overlap with VIDWIN1.
The OSD cannot support more than 256 color entries in the CLUT RAM/ROM. Some applications
require higher number of entries, and one workaround is to use VIDWIN1 as an overlay mimicking the
OSD window. Another option is to use the RGB mode for one of the OSD windows which allows for a
total of 16-bits for the R, G, and B colors (64K colors).
The OSD can only read YCbCr in 422 interleaved format for the video windows. Other formats, either
color separate storage or 444/420 interleaved data is not supported.
If the vertical resize filter is enabled for either of the video windows, the maximum horizontal window
dimension cannot be greater than 720 currently.
It is not possible to use both of the CLUT ROMs at the same time. However, one window can use
RAM while another uses ROM.
The 24-bit RGB input mode is only valid for one of the two video windows (programmable) and does
not apply to the OSD windows.
The OSD register memory mapping is shown in
Table 5-53
.
Peripheral and Electrical Specifications
162