XC 33
I2
T
_
"
PAMI
SEL
C 3 ’
\ §
J - s s r r r
’I
I0
Low
Level
8
xc 33
,O
\w
en
amz
SEL
9
_
, , 3 ’
,Z
ii-931
lfegel
lC137
74LS139P
ABQ
Ivo
A89~$EL
ABM
IA
\v-
_ / § A _ § ? ‹ f
RAM
_
B
:if
WEEE
Expansion
Connector
T815
_
Aan
4
’ ; E F ‘ S £ ~
AB|2
ze
zvz
’
’
53
2"
i
1c|3a
+5v
Fig.
5-5
Address
Decwder
Circuit
for
RAM
gf,
-_=3g_255MH,
(Basic
Oscillating
Frequency)
fD@0=1s.12a:~1H=(eocn
Mode
dot
’:-----;___-)(80Cl;(
otsf
FreqØency)
39-53#5(I-Iorizontal
diiplaf’
period)
¢fw=
s_oe4MH1
(4Och,
Mode
not
= X40c§d
Bdoism
.
d)
Frequency)
-
(
orizontal
isp
ay
perio
fCw=
2-016MHz
(8Och,
Mode
Character
$-
Frequency)
Dots
f C =
1~ 5MH1
(4Och,
Mode
Character
=
tv..
..
\
1:
1.
@ q u ‹ i ’ 1 C Y ;
0
fr;
=1.008MHz
(MPU
Operation
Clock
Frequency)
f m - : x r 1 . = 4 . 0 3 2 M H 1 ( M P U
Operation
Clock
Frequency)
o
f,,=15_75KH2
(Horizontal
= % = % _
Synohronise
4
U
/v
=60Hz
( a ; g % § % a ‹ r e q u e n ; ! m ’ -
§ § 3 § a i 1 ? » § Ø - e
L 1 ‹ 1 ’ 1 C § ? f 2
~5
|c43
IC37
|c i
|cas
ncaa
H
Dis
la
Address
Signals
LII-I
A
N
we
P
Y
fu
fv
V000
_
!|
Video
Signal
Generation
Circuit
-1
74S04P
74S163N
HD6809P/MC680?L
74LS157P
HD46505SP
’
cao
4Oc1’1/ Och
Switch
Signal
Fig.
5-5
Clock
generator
circuit
Summary of Contents for MB-6890
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Page 2: ...HITACHI PERSONAL COMPUTER MB 6890 SERVICE MANUAL ev O 30 1 2 1 ...
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