Filter
Top Products
YMF744B
February 3, 1999
-49-
7. Zoomed Video Port
Zoomed Video Port is defined in the PC Card Standard (PCMCIA) applicable to the notebook PC or other
systems. This port is used to directly output video and/or audio signals onto the PCMCIA bus for D/A
conversion process, and connect them directly to the video and/or audio signal processing chips on the PC
system. Its major applications include MPEG decoder card and video capture card, etc.
Because the video and/or audio signals on the Zoomed Video Port have been output in synchronized
condition, DS-1S only converts input audio signal into analog signal through D/A converter.
Audio signals to be transferred on the Zoomed Video Port include bit clock (SCLK), L/R clock (LRCK) and
serial data (DATA), and they are provided as outputs in the format defined below. This is generally called
I
2
S format.
1514131211109876543210 1514131211109876543210
LEFT Channel RIGHT Channel
SCLK
DATA
LRCK
In the Zoomed Video Port, synchronization with a master clock supplied from the bus is inherently required.
However, DS-1S can asynchronously process audio signal input via the Zoomed Video Port, eliminating the
need for master clock.
Sampling rate of the audio signals input via the Zoomed Video Port is resampled to 96.0kHz sampling
frequency at the stage followed by the SRC block, then converted to 48.0kHz sampling rate in the SRC block
stage. Sampling rates to be supported on the Zoomed Video Port include 22.05kHz, 32.0kHz, 44.1kHz and
48.0kHz.
Interface connection arrangement between the DS-1S and the Zoomed Video Port is as illustrated below.
ZVBCLK
DS-1S ZV Port
ZVLRCK
ZVSDI
MCLK
DATA
LRCK
SCLK
Open
80
78
79
The Zoomed Video Port can be used to be selected between the SPDIFIN input.