Sony BVH-2000, Operation And Maintenance Manual

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(5-6-5. Control Panel)
3. Display Control Block
The LEOs inside the switch, SEARCH LED, buzzer and
fluorescent display are controlled by the display control section.
The LEOs inside the switches in FEOOH,
FEOIH, FE02H. FE03H, FE05H and FE07H, and the SEARCH
LED is
in address FE04H.
When the CPU is data, the switch and SEARCH LEDs
are selected: when it is reading data the key matrix is selected.
The data, input from the CPU on the SY-79 board through the
data bus,
first latched, and the ON/OFF of the
LEOs inside the switches and SEARCH LED are controlled in
accordance
with the data.
The buzzer control port
FE06H. When the VTR malfunctions and the buzzer sounds
continuously, it is controlled bit-7 of the FE05H address.
It
is
controlled bit-O of the address
sounded once for confirmation when a switch has been
The SEARCH dial clutch is controlled by bit-2 and bit-l of
address FE06H. For
PROGRAM JOG mode, a click is added to the SERACH dial at
the STILL, ± 1 and ±3x speed positions.
The time code, timer, tape alarm message and edit point
can be displayed on the fluorescent display. The type and
number of characters which
display differ according to the type of control which is
being used.
BKH-2011:
BKH-2012:
5x7-dot/40-character,
BKH-2013: 5x7-dot/40-character, double-row display
BVH-2000(U/C)/PS/PM
BVH-2180(U/C)/PS/PM
The to BKH-2013.
The display data from the SY-19 CPU for the top row of the
fluorescent into refresh memory IC21 and
ICl4
input into IC9 and ICl3 (RAMs). In accordance with addresses
to AO, the data are stored one character at a time in the
out
address counter, which will be described later. The top row
display data are written into addresses FFOOH to FF7FH~ the
FFFFH.
The
The clock generator IC36 oscillates a 40kHz. This
is
divided down by 8 at IC39 to 5kHz and the resulting clock
address counter output passes through the multiplexer IC20 and
IC29, it simultaneously
accesses the address inputs of the
top
data are read out in sequence one character at a time.
The display data, which are now read out are converted into 35-
and
pass the anode driver and into the fluorescent
display. The grid pins( G 1 to G40) of the fluorescent display are
driven
the to IC19 the
counter/decoder IC23 to IC27. This has the effect
pins G 1 to G40 in sequence and in displaying the pattern, which
into common anode, at the
DISPLAY CONTROL BLOCK FOR BKH-2013
FROM SY-79
5-6-7
SYSTEM CONTROL SYSTEM
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