Sony BVH-2000, Operation And Maintenance Manual

Page: 335 / 505

5-7-6. RL-12 Board
1. Outline
The RL-12 board houses the hardware required to control the
reel motors. It is controlled by the data from the SV-43 board
The RL-12 board also houses a generator circuit for generating
interrupt
signal for the CPU on the SV-43 board
The main circuits accommodated on the RL-12 board are:
8-Bit
ND
Converter for Analog Voltage Detection
D/ A Converter for Control
Supply/Take-up Reel Tension AC Feedback Loop
Reel Rotation Detector
Timer Roller Rotation Detector
Interrupt Signal Generator
2. 12..Bit Converter for Analog Voltage Control
z
o
I-
«
a:
w
CL
o
LL
o
>-
a:
o
w
I
l-
ui
The data required to control the analog voltage (motor control)
are from the SV board to the board and are
converted into analog signals by the 12-Bit D/ A converter IC4.
SVD7~
SVD6~
SVD5~
SVD4~
SVD3~
SVD2~
SVD1~
SVDO~
SERVO SYSTEM
The D/ A converter IC4 serves to convert by time-sharing the
euurvatent to 8 channels whose data are by the
WRITE ADDRESS:5018H/Bit-2 (LSB) to Bit-7 and 5019H/Bit-0
to Bit-5 (MSB). These signals are selected by the demultiplexer
IC6 in accordance
with the CPUs output port IC2F
ADDRESS: 501AH/Bit-2, -1, -0) and are output to the various
systems.
IC2F:WR ADDR SOIA
H
SELECT I ON OF
B 1 T- I
BIT-O
DI
A OUTPUT DATA
0 0
0
S--REEL MDA
-~-----
----------_._-
0 0 1 T-REEL MDA
-----
0 1 0 DRUM VELO CONT
_.
f------
0 1 1 CAPSTAN VELO CONT
-- ------ ~----------------
1 0 0
SPARE
-----
--.-------------
1 0 1
SPARE-l
--
-----
--~---------------
1 1 0 PLAY S - REEL TENS I ON CONT
_.
_.
1 1 SPARE-2
The output of IC2F is read again into the CPU via IC2F and
reconfirmed
5-7-12
BVH-2000( U/C)/PS/PM
BVH-2180(U/C)/PS/PM