5-1 (E)
MAV-555
Section 5
Circuit Description
1. Reference Block
The REF signal that is used as the reference of the main
unit is selected as described below. On the CN-1816
board, one of the REF signal and R1/R2 COMPOSITE
VIDEO IN signal at the input terminal on the rear panel is
first selected and output to the TM-40 board. This selec-
tion control signal is output from the TM-40 board. On the
TM-40 board, moreover, the timing signal produced from
the selected signal and the timing signal produced from an
R1 or R2 SDI IN signal are selected and used as the REF
signal of the main unit. The video and audio signals at a
PB port and the MONITOR OUT video and audio signals
output from the EM-1 board use this REF signal as
reference. The signal that controls the time slot at each
port also uses this REF signal as reference. The data
transfer, recorded and reproduced in HDD, between the
DM-120 and PU-109 boards is also performed in synchro-
nization with this REF signal.
2. Video Block
REC mode
A video signal is usually input from the SDI (COMPO-
NENT) IN terminal of an R1 port. The SDI signal input to
the rear panel is directly sent to the DPR-127 board via a
coaxial cable. The SDI active through signal produced on
the DPR-127 board is also directly sent to the real panel
via a coaxial cable. If BKMA-511 (option) is inserted into
each port, the analog composite signal input to the COM-
POSITE IN signal terminal on the rear panel is passed
through the buffer on the CN-1816 board and input to the
AD-160 board via the MB-845 board. On the AD-160
board, the analog composite signal is Y/C-separated. The
C (chroma) signal is also decoded to B-Y and R-Y signals,
converted into three (Y, B-Y, and R-Y) component signals,
and input to the DPR-127 board. On the DPR-127 board,
the input signal from the SDI IN terminal and the signal
from the AD-160 board are selected to compress a video
signal. The compression system is MPEG2 4:2:2 Profile
@ML. An intra-frame is compressed in this case. The
compressed vide data is converted into an HDD-write
format (packing), multiplexed with audio data, and output
to the DM-120 board. On the DM-120 board, the data is
loaded into memory once and transferred to the PU-109
board as video data and HDD command data in synchroni-
zation with the time slot signal in equipment. On the PU-
109 board, the video data is processed so that it is distribut-
ed to each HDD (8
+
parity). The processed video data is
then output to the IF-751 board corresponding to each
HDD in a ratio of 1 to 1. On the IF-751 board, data is
written in HDD via SPC (SCSI Protocol Controller).
In this case, the information on the area of HDD in which
data is written is obtained from the file system memorized
in the FM-68 board when the video data is transferred from
the DM-120 board to the PU-109 board. The information
is added immediately before the video data as command
data and output to the PU-109 board.
PB mode
Information is obtained from the file system memorized in
the FM-68 board, and PB control data is output from the
DM-120 board to the PU-109 board. The PB control data
is decoded by the PU-109 board and the corresponding
video data is read from HDD. The video data is sent to the
DM-120 board through the IF-751 and PU-109 boards. On
the DM-120 board, the video data sent from the PU-109
board is stored in memory once and one-frame video data
is output to the DPR-127 board during one-frame period.
On the DPR-127 board, the video data is converted from
an HDD write format (depacking), input to an MPEG2
decoder, and decoded to a video signal. The decoded
signal is output from the DPR-127 board to the rear
connector panel as an SDI (COMPONENT) signal via a
coaxial cable. If BKMA-512 (option) is inserted into each
port, the video signal decoded using an MPEG2 decoder is
output from the DPR-127 board to the DA-136 board and
converted into a composite signal.
The video signal is then converted from digital to analog
and output as an analog composite signal through the MB-
845 and CN-1816 boards.
Monitor system and others
The four signals in recording systems (R1 and R2) and
playback systems (P1 and P2) are sent from the DPR-127
board to the EM-1 board as a monitor signal. One of these
signals is selected on the EM-1 board. The selected signal
is mixed in characters, converted into an SDI signal, and
output to the rear panel via a coaxial cable. After the
output signal is converted into a composite signal, it is
converted from digital to analog and output to the rear
panel through the MB-845 and CN-1816 boards as an
analog composite signal.
Moreover, animation data is output from the EM-1 board
to the control panel (BKMA-505). The video signal at
each port is selected using a router by the control operation
from the control panel. The video signal is then converted
into an analog composite signal and output through the
MB-845 board to the multi-connector on the front panel
and the rear panel as a control panel signal.
