signals.
In
this
conversion
period,
shift/Load
signals
are
inputted
to
ICll7
15
pin
which
makes
it
possible
to
output
video
signal
during
display
period.
(2)
Data
bit
from
colour
RAM
makes
the
timing
per
each
l
character
at
1c115
9
pin
input
(LOAD
signal)to
synchronize
with
brightness
signal
which
was
derived
from
ICll7.
(3)
The
brightness
signal
is
combined
with
display
reverse
signal
(REV
signal)
from
colour
RAM
at
ICl36
then
combined
with
cursor
display
signal
(CUR
DISP
signal
at
ICl3l.
I
(4)
To
make
the
synchronization
with
this
brightness
signal
and
colour
inform-
ation
signal
from
colour
RAM,
timing
is
set
per
each
l
dot
at
input
6
pin
(DOT
CK
signal)
of
ICll6.
Then,
after
switching
of
background
colour
signal
(R~BK,
G-BK,
B-BK)
of
ICll8
and
colour
signal
(R,
G,
B)
of
colour
RAM
to
brightness_signal
at
l
pin
input,
output
of
G
signal
to
4
pin,
R
signal
to
7
pin
and
B
signal
to
9
pin
of
ICll8
are
done.
After
reverse
buffering
these
signals
in
ICl32,
colour
display
colour
raw
signals
R,
G,
B
are
outputted
to
colour
display
connector;
(5)
R,
G,
B
signals
are
composed
with
synchronous
signal,
which
are
made
from
ICl32
and
ICl35,
at;/A
converter
then,
after
impedance
conversion
Q5,
these
signals
are
outputted
to
mono-chrome
video
terminal.
(6)
On
the
hand,
synchronous
signal
is
counted
by
synchronizing
the
E
(1,008
MHzl
signal
from
MPU
and
H
SYNC
signal
from
CRTC
in
ICl34,
ICl35,
then
out-
putted
to
IC96
pin
3
as
pulse
width
=
4ps
horizontal
synchronous
signal.
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graphic
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Fig.643
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Relationship
between
display
mode
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resolution
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Summary of Contents for MB-6890
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