Fusion 878A
1.0 Product Overview
PCI Video Decoder
1.2 Detailed Features
100600B
Conexant
1-7
The clock signal interface consists of a pair of pins that connect to a 28.63636
MHz (8 × NTSC Fsc) crystal. Either fundamental or third harmonic crystals may
be used. Alternatively, CMOS oscillators may be used.
1.2.12 GPIO Port
The Fusion 878A provides a 24-bit GPIO bus. This interface can be used to input
or output up to 24 general purpose I/O signals. Alternatively, the GPIO port can
be used as a means to input video data. For example, the Fusion 878A can input
the video data from an external digital camera and bypass the Fusion 878A’s
internal video decoder block.
1.2.13 Vertical Blanking Interval Data Capture
The Fusion 878A provides a complete solution for capturing and decoding VBI
data. The Fusion 878A can operate in a VBI Line Output Mode, in which the VBI
data is only captured during select lines. This mode of operation enables
concurrent capture of VBI lines containing ancillary data and normal video image
data.
In addition, the Fusion 878A supports a VBI Frame Output Mode in which
every line in the video frame istreated as if it were a VBI line. This mode of
operation is designed for use with still frame capture/processing applications.
1.2.14 I
2
C Interface
The Fusion 878As I
2
C interface supports both 99.2 kHz timing transactions and
396.8 kHz, repeated start, multi-byte sequential transactions. As an I
2
C master,
Fusion 878A can program other devices on the video card, such as a TV tuner as
long as the device address is known. The Fusion 878A supports multi-byte
sequential reads (more than one transaction) and multi-byte write transactions
(greater than three transactions), which enable communication to devices that
support auto-incremental internal addressing.
1.2.15 HDTV Support
Fusion 878A has the ability to accept either serial or parellel HDTV data and
deliver that data to the host. Serial and parellel inputs both use the audio DMA
channel to transfer the HDTV MPEG packets to the host.
Serial HDTV streams may be input to the high speed serial port, which shares
pins with the digital audio (I
2
S) port. Fusion 878A will accept serial HDTV
streams at up to 40 Mbps.
Parellel HDTV data may be input to the GPIO port in asychronous parallel
mode at up to 20 Mbps.