BT848 ETC, BT848 Datasheet - Page 12

• Manufacturer Part Number: BT848
• Description: Single-Chip Video Capture for PCI
• Manufacturer: ETC

F
Functional Overview
Bt848A Analog Video and
2
UNCTIONAL
Digital Camera Capture
Over the PCI Bus
DMA Channels
D
ESCRIPTION
Table 1. PCI Video Decoder Product Family
The Bt848A provides support for digital cameras. The Bt848A includes a digital
camera port providing the ability to perform digital capture when a Bt848A is used
in the development of a video board product. The Bt848A is fully compatible with
the Bt848. The datasheet defines the registers and functionality required for imple-
menting analog video capture support. In order to implement digital video inter-
face, refer to the Digital Video section of the datasheet. Note the majority of the
register settings are identical for both analog and digital video support. The Digital
Video section identifies all changes, additional registers, all changes to the analog
register setting that are required in order to support digital video.
Silicon Vision and Logitech video cameras. The digital stream is routed to the high
quality down scaler and color adjustment processing. It is then bus mastered into
system memory or displayed via the graphics frame buffer.
Bt848/848A/849A provides two DMA channels for the odd and even fields, each
controlled by a pixel instruction list. This instruction list is created by the Bt848
device driver and placed in the host memory. The instructions control the transfer
of pixels to target memory locations on a byte resolution basis. Complex clipping
can be accomplished by the instruction list, blocking the generation of PCI bus cy-
cles for pixels that are not to be seen on the display.
in packed or planar format. In packed mode, YCrCb data is stored in a single con-
tinuous block of memory. In planar mode, the YCrCb data is separated into three
streams which are burst to different target memory blocks. Having the video data
in planar format is useful for applications where the data compression is accom-
plished via software and the CPU.
Composite, S-Video multi-standard Video
Decoder and PCI bus master
Peaking, single crystal operation, digital camera
support
WST (Teletext) decoding support
The Bt848A can accept digital video from a multitude of sources including the
The DMA channels can be programmed on a field basis to deliver the video data
L848A_A
Single-Chip Video Capture for PCI
Bt848
X
Bt848A
Bt848/848A/849A
X
X
Brooktree
Bt849A
X
X
X
®