Hitachi MP-1802 Technical Manual page 32

7 - 3
M D D ( t ' t i n i D i s k D r i v e )
U n i t
( 1 )
G e n e r a l
T h e M D D r o t a t e s
t h e d o u b l - e - s i d e d d o u b l e d e n s i t y
5 + i n c h d i s
w i t h a D C m o t o r a t 3 0 0 r p m a n d t r a n s m i - t s t h e d a t a a t
2 5 0 K b i
s e c . W i t h t h e M F M r e c o r d i n g m e t h o d , 1 6 3 . 8 l + K b y t , e / s l d e x 2
s i d e s = 3 2 7 . 6 8 K b y t e s o f d a t a i s r e c o r d e d o n / t 0 t r a c k s
b y
1 6 s e c t o r / t r a c k
f o r m a t t i n g .
A t u n n e l e r a s e r e a d / w r i t e
h e a d i s u s e d a n d a c e u r a t e t r a c k i n g
i s
a c h i e v e d w i t h
a 4 . - p h a s e s t e p p i n g
m o t o r a n d s p i k e w h e e l .
F i g . 7 . 9 s h o w s t h e M D D b l o c k d i a g r a n .
I,/O enable
S€LECr 0
S€LECT I
IVRITE OATA
W R I T E C A T E
DERECTION IN
STEP
HEAO LOAO
MOTOR ON
R€,AO OATA
I N O E X
R E A O Y
+ 5 V
+ t a ,
powe|:r on
--rese
F i g .
7 . 9 M D D B l o c k D i a g r a m
o q
C'
Ir-l
s
+,
a
+J
Ft
dt
+J-
e
o ()
d
tH
b
+J
a
td
+J
A
o
q
.r{
te
inhibit
read
voltage
head
lold
'
, . , / 3 0
W R I I E P R O