Table of Contents
Advertisement
(2) Audio system (AXM-14 board (1/2), CNB-1
board (1/2), TC-80 board (1/2), and RX-26
board)
The audio system of the Betacam SX recorder has the
configuration of the four input channels with the two
output channels.
The CH-1 and CH-2 have the "AUDIO IN" switches
which select their input signals from either the LINE/MIC
input (rear input) signals coming from the XLR connectors
on the rear panel, or the camera MIC input signal (CH-3)
coming from the camera, or the wireless audio input signal
(CH-4) coming from the slot-in wireless receiver, to be
recorded on tape.
The selected input signal is A/D converted and sent to the
audio data processor as the AU A/D data (1/2 and 3/4).
The output signal from the audio data processor is D/A
converted, and the CH-1 and CH-2 signals are output from
the 5-pin XLR connector.
The earphone and internal speaker have the "MONITOR"
switch which selects either CH-1, MIX, or CH-2 signal to
be output the earphone and internal speaker.
4-2
(3) System control (DVP-1 board (2/2), TC-80
board (2/2), KY-293 board, HN-224 board (1/2),
and AXM-14 board (2/2))
Among the captioned circuit boards of the system control
block, the DVP-1 board controls its peripheral boards and
the entire system, while the TC-80 board controls the
system unique to the machine such as time code, display,
and key panel. The CT-187 board controls the analog
video input and output systems.
. DVP-1 board (2/2)
The DVP-1 board (2/2) has the system control CPU that
is the center of the system control. A 16-bit CPU operat-
ing on a clock speed of 20 MHz, is used for the system
control CPU because it handles large volume of data in
such a case as communication with digital processors.
Regarding communication, the parallel interface of the
DVP-1 board is established after level-shift
(from 5V→ 3.3 V) because the parallel bus interface
system such as digital processor ICs, operates on 3.3 V.
The serial interface system can be interfaced directly
with the SIO of the CPU. However, because the CPU
must establish serial communication with the SERVO
MPU and TC MPU in addition to the SIO of the CPU,
the SIO is shared and is switched to either SCI (DPR) or
SCI (SV) or SCI (TC) by the SCI selector.
For the serial communication with the CT MPU, another
SIO is used for interface because the CT MPU uses the
different type of synchronization systemfrom VTR
block. An I/O expander covers an insufficient numbers
of the I/O port.
. TC-80 board (2/2)
The TC MPU on the TC-80 board (2/2) controls TC IC
(LTC reader and generator) while communicating with
the system control CPU in serial communication. The
TC MPU also controls the LCD module, key matrix, and
character generator via the I/O expander.
A backup power supply using a lithium battery is used to
back up the generator circuit and real-time data.
. CT-187 board
The CT MPU on the CT-187 board controls superimpose
of the menu and short data, VTR REMOTE terminal
communication, and analog video input and output.
DNV-5
Advertisement
Table of Contents
