cx25870 Conexant Systems, Inc., cx25870 Datasheet - Page 84

• Manufacturer Part Number: cx25870
• Description: Video Encoder With Adaptive Flicker Filtering And Hdtv Output
• Manufacturer: Conexant Systems, Inc.

1.0 Functional Description
1.3 Device Description
Figure 1-33. DVD Playback Utilizing Graphics Controller for Color-Space and Progressive Scan Conversion
1-68
DVD-ROM
Drive
Mbit/s
10
Adapter
Host
be able to deinterlace and color space convert the CCIR601 input data from the
MPEG2 decoding source. Furthermore, since the pixel clock frequency is not
27.000 MHz any longer, the graphics controller must have the ability to
synchronize the pixel data to the clock rate dictated by the CX25870/871s CLKO
signal. Finally, the controller must be able to function as the clocking master and
timing slave as described in
and the encoder must be programmed to accept noninterlaced RGB data and
output a standard NTSC video output. The pertinent factors for this option are:
architectural option. As a result, simply use the graphics accelerator’s serial bus
mastering ability to program the CX25870/871s CONFIG[5:0] field with a binary
value of 101100. This translates into writing a hexadecimal number of 0x54 to
register 0xB8. Once the encoder acknowledges this write to its autoconfiguration
register, it automatically loads the appropriate values for this type of DVD
configuration into its register indices from 0x76 to 0xB4 including 0x38. The
exact data transferred into these registers is contained in
• Type of Digital Video Input:
• Active Resolution (HorizontalxVertical):
• Overscan Compensation Ratio:
• Interface:
• Pixel Rate
• Type of Analog Video Output:
Parsing
Stream
This design is illustrated in
To enable DVD playback with this architecture, the graphics controller must
The recommended interface for the CX25870/871 for this option is Master
Given this set of conditions, autoconfiguration mode 44 is a perfect fit for this
100 kbit/s
450 kbit/s
Mbit/s
15
Conexant
Subpicture
Decoder
MPEG-2
Decoder
Decoder
AC-3
Flicker-Free Video Encoder with Ultrascale Technology
Section 1.3.7
Mbit/s
Figure
20
Accelerator
Graphics
Sound
1-33.
Card
Progressive Scan/Noninterlaced; 24-bit RGB
per pixel Multiplexed Input Format
720x480
Minimal; Horizontal = 1.24%; Vertical = 1.23%
CX25870/871 is clock and timing master
27.6923 MHz
Standard NTSC[NTSC-M]
of this data sheet.
CX25870/
CX25871
Speakers
Monitor
CRT
Appendix
NTSC or PAL
CX25870/871
Television
C.
100381B
100381_061