System Control (At-148 Board); Bvp-E30/E30P M-V1 - Sony BVP-E30 Maintenance Manual

IF-969 Board
The IF-969 board is composed of the driver block which
switches and outputs the analog signals D/A converted by
the DPR-261 board and RET signal sent when CCU is
connected to each block, and the I/O block inputs/outputs
the control signals from/to the lens, VF and the camera
adaptor.
The VBS signal which is D/A-converted by the DPR-261
board is input to the IF-969 board and branched into two.
One is sent to the camera adaptor as VBS output by 75 Z
output driver after passed through the video driver IC
(IC105). The other is switched by the analog switch IC
(IC104) and output at the TEST OUT terminal.
This unit has the two systems to output the TEST signal.
One system outputs the TEST signal as a MONITOR OUT
to the camera adapter after being switched by IC104
analog switch.
The other outputs that at the TEST OUT terminal by the
75 Z output driver after passing through IC105 driver IC.
At this terminal, VBS, TEST or RET signals which is
selected by IC104 analog switch is output. According to
another switch setting, character signal can be added to the
above output signal.
The RET signal sent when CCU is connected and the
GENLOCK input signal from the camera adaptor are
switched by the analog switch circuit (Q101 to Q107) and
the RET signal is separated to two pathes. The one is
output at the TEST OUT terminal via the analog switch IC
(IC104) after switching between the RET signal and the
TEST signal is done by the analog switch circuit (Q126,
Q115 to Q117, IC2). The other is output to VF VIDEO
OUT after switching between the RET signal and the VF-
VIDEO signal is done by the analog switch circuit (Q4 to
Q6).
To synchronize the GENLOCK input of the camera
adaptor with the external input video signal, the IF-969
board is provided with the floating amplifier circuit and
sync separation circuit to send the external sync signals
EXT-SC and EXT-SYNC to the DPR-261 board.
When a color VF is connected, the signals VF-Y, VF R-Y,
VF B-Y input from the DPR-261 board are mixed with the
cursor, marker signal and character signal generated in the
character generator IC (IC5) and then output as a COLOR
VF signal.
When a white/black VF is connected, the VF-Y signal
input from the DPR-261 board are mixed with the cursor,
marker and character signals in the different block to the
COLOR VF signal and then output to VF VIDEO OUT as
a monochrome VF signal.
1-12 (E)
The I/O block controls the switching input signal from the
switches of the camera, input/output signals from/to the
camera adaptor and lens, and output signal to VF using the
I/O expander (IC307) which communicates with the AT-
148 board.

1-7-3. System Control (AT-148 Board)

AT-148 Board
The AT-148 board is provided with a CPU (IC11) which
performs system control.
It is operated by the program written in the ROM (IC231
and IC232). The program can be upgraded using a memory
stick via the controller IC222.
The AT-148 board is also provided with a general memory
SRAM (IC216 and IC217) and FRAM (IC220 and IC221)
for recording system setting conditions, etc.
The external 8-bit bus (IC205, IC206, IC207, and IC208)
controls the I/O expander (IC307) of the IF-969 board and
the digital signal processor LSI (IC1). It also controls IC1
of the TG-229 board, IC104 of the NR-72 board, D/A
converter of the VA-226 board (IC702 and IC704), D/A
converter of the DPR-261 board, and switch input (IC1001
and IC1002) of the CN-2205 board by serial communica-
tion.
The A/D converter of the CPU reads the IRIS, ZOOM, and
EXTENDER signals from the lens, and controls the lens
via the channel B of the communication IC (IC224).
In additional the CPU performs temperature control using
the temperature sensor signal of channel G sent from the
CCD block (PA-273 board), position control from the filter
block, tape remainder control, and audio volume control.
It is also provided with the serial I/O which communicates
with the CCU using the 700 protocol (channel A of IC224)
and the calendar function (IC3).

BVP-E30/E30P M-V1