Service manual
PC
1GOO
3. Block diagram
D. - 0 ,
B
A.
-AI
,
FROM
CE-l6OOP
(PR
INTE
R)
I
07N.
WR, AD,
,
AS
TN
r--'
POWER
ON
RESET
CIRCU IT
Vee
(+5V)
AEGURATED
,
r--'
POWEA
SUPPLY
CIRCU
IT
Vp I-tfiV)
SOP
CO
NNECTOR
4. Circuit desc
ri
pt
ion
4·',
Internal operat
io
n
Since the floppy disk controller
is
contained within the
2.5"
floppy disk
dr
ive
unit and directly interfaced
wi
th the
bus line, data line and control signals are directly con-
ne
cted.
So, only the power-
cn
-reset signal generation circuit and
the amp's
5VC
(
+5V)
s
upply
regula
to
r
circuit
are
pro
vided
for
circu
it
.
4·2. Power
-o
n-re
se
t
si
gnal
ge
neration circuit
vee
R'
RSTN _
___
__
+
__
__
REST
vc<
04
Fig. 1 R
.-t
circuit
O
~
- D,
RAN
1ft
~
ERASE
FDC
•
~
LO
GIC
A.
- A.
~
RIW
AMP
LSI
RO
I<-
GATE
ARREY
eso, WA, AD,
SOLE
NOID
- 99 -
REST
r
'I
I
SOLENOID
CONTROL
CI
RCUIT
.,v
~
p-
'VB
n
,ve
MOTOR
CONTROL
_6v
CIRCU IT
FOU-
250
MICRO
FLOPPY
DISK
DRI
V E
UNIT
POWER
ON
:/~
------
-
~+~~
vee
___
--"-
~~
~
, '
<&>
"
__
~'~:
L
O
'
I
~V
,
System
re$E!t
, ,
,
,
~':~
""---X----,,,,--
I------,
rlJ
H
L
F
ig.
2 R
.-t
ti
m ings
F
i9.
1 shows
the
reset circuit and F
ig.
2 shows
iu
timin
gs.
RS
is a charge curr
ent
reg
ulati
ng
res
i
sto
r C3 which is
us
ed
for pullup and delay. D4
is
a diode w
hi
ch
is
used
to
bypass
the cha
rge
in
C3
to
vee line when vee
is
off.