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(3) WON: WRITE-DATA -NRZ
This inputs serial data at writing in the disk
.
(4) AMW
:
AM -WRITE
This should be active high at writing data (address
mark), including m issing clock
.
(5) AE
D:
AM -ENABLE-D
Act ive high
;
this is input as a m iss ing clock search
(address serch) signal in Read -operations
.
This enables
a writing index mark in the floppy disk, by activating
w ith IAMW
.
(6) R D M
:
=R-=-A=w;-;:-D"A"""' T ;:-;A,-- -M.-.
If this signal is at a low voltage level _[n address-mark
searching, this counts the input Raw Data, and internal
Read-conditions will be satisfied
.
(7) PED
:
PRECOMP-EARLY-DATA
This inputs a signal for Wr ite procompensation and
becomes early data at the external selection in the
mode
set.
3) OPEATIONS
3)-1. Reset Input
1.
RST (RESET)
Active high; this clears all the registers including all the
registers that initialize this chip.
3)-2. Clock Input
1. 4FC (4F-CLOCK)
A basic clock used for internal control and the Write
circu it. A half circle of th is is output as 2F -Ciock.
2.
VCK (VCO -CLOCK)
This inputs an output clock of the VCO circuit
_
In Read
operations
,
the clock generated from this clock is output
as Read -Clock.
3)-3. Clock Output
1.
2FC (2F -CLOCK)
This inputs a half circle of the 4F -Ciock
.
2. RCK (READ-CLOCK)
In Read operations
,
the clock generated from the VCO
clock is output synchronically with Read -Data. In
non-
reading
,
a negative clock of 2F-CLOCK is output. This is
temporarily set high at the switch ing point with 2F
-
CLOCK.
3)-4. Raw-Data
Input and Drive Select Signals
(RR1, RR2 & DS1)
This inputs receiver output of the data sent from the disk.
Depending on DS1, either RR1 or RR2 will be selected.
The relationship between OS 1 and R R
1,
R R2 is the f
ol
low-
ing.
DS1
RR1/RR2
Low Level
R R 1 will be selected
Heigh Level
RR2 will be selected
The reading edge of R R 1 and R R2 is basically the rising
time by the disk
.
-
'l:l
-
3)-5. Read Control Signals
1. RGT (READ-GATE)
-
M Z
-
5600A
Active high
;
Gate signal for all the Read operations.
2
.
AED (AM -ENABLE -D)
Active high
;
this should be active when missing clock
data (address mark) is to be searched. With
t
his signal
and the AMW signal hish
,
in Read operations and in
Write operations at the floppy disk mode, an Index mark
is enabled.
3)-6 Write Control Signals
1.
WGT (WRITE -GATE)
Active high
;
Gate signal for all the Write operations
.
IVCK and Read Strobe (IRSE
,
IRSN
,
IRSL)
@
iVCK
_ _ _ /
r
-
data
separato
window
(interna
I)
cw
typ 10.7ns ___.
window
i
RSE, iRSN
,
iRSL
f-typ 12 .6ns
window
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