Sony OA-D30V User manual

@>
u\jJ~ Jj.FJD IF LD JlJl¥lfJ J~J1 JJfJJ ~~
MODEL OA-D30V
OEM MANUAL
SON~

PROPRIETARY NOTICE
This manual contains proprietary design information. Repro-
duction or dissemination of information provided herein, for
purposes other than operation and maintenance of the equip-
ment, is strictly prohibited without written consent from the
SONY Corporation.

RECORD OF REVISIONS
REVISION NOTES
1 ORIGINAL ISSUE
October, 1981
2 March, 1982
n

CONTENTS
Description
SECTION 1. INTRODUCTION ....................................... .
1-1 . Purpose.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2. General Description ................................ .
SECTION 2. FUNCTIONAL CHARACTERISTICS .......................... 3
2-1. GeneraIOperation .................................. 3
2-2. Read/Write and Control Electronics. . . . . . . . . . . . . . . . . . . . . .. 3
2-3. Drive Mechanism ................................... 3
2-4. Positioning Mechanism ............................... 4
2-5. Disk Chucking Mechanism ............................. 4
2-6. Read/Write Head ................................... 4
2-7. Recording Format .................................. 4
2-8. Floppy Disk Controller Chips ........................... 4
SECTION 3. SPEC IFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3-1 . Drive Performance .................................. 7
3-2. Dimensional Data ................................... 7
3-3. DC Power Requirements .............................. 7
3-4. Environmental Considerations ........................... 7
3-4-1. Reliability and Maintainability .................... 7
3-4-2. Environmental Limits .......................... 7
SECTION 4. INTERFACE DESCRIPTION ............................... 9
4-1 . Host System Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4-2. Interface Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4-2-1. Input Signal Requirements ....................... 9
4-2-2. Output Signal Characteristics ..................... 9
4-3. Signal Interface .................................... 9
4-3-1. Input Signal Descriptions ........................ 9
4-3-1-1. Drive Select 0, 1 ........................ 9
4-3-1-2. Direction Select (DI RTN) ................. 11
4-3-1-3. Step. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4-3-1-4. Head Load (H DLOAD) ..... ~ ............. 11
4-3-1-5. Write Data (WRTDATA) .................. 12
4-3-1-6. Write Gate (WRTGATE) .................. 12
4-3-2. Output Signal Descriptions ....................... 13
4-3-2-1. Index ............................... 13
4-3-2-2. TrackOO (TRKOO) . . . . . . . . . . . . . . . . . . . . . . . 13
III

CONTENTS
Description
Page
4-3-2-3. Write Protect (WRTPRT) .................. 14
4-3-2-4. Ready
.............................. 14
4-3-2-5. Read Data (RDDATA)
................... 14
4-4. Interface Timing
.................................... 15
SECTION 5. CONTROLS AND INDICATIONS . ........................... 16
5-1. Operator Controls and Indicators
......................... 16
5-1-1. Front Panel Controls ........................... 16
5-1-2. Front Panel Indicators .......................... 16
5-1-3. Rear Panel Controls
........................... 16
SECTION 6. OPERATION . .......................................... 17
6-1 . Disk Description .................................... 17
6-1-1 ~ Disk Preparation and Write Protection ............... 17
6-2. Operation
........................................ 18
6-2-1. Disk Eject Mechanism
.......................... 18
6-2-2. Disk Insertion
............................... 18
6-2-3. Disk Removal ............................... 18
6-3. Disk Precautions .................................... 18
6-4. Disk Environmental Limits
............................. 18
SECTION 7. ELECTRICAL CONNECTORS .............................. 19
7-1. Power Connectors
................................... 19
7-1-1. Frame Ground ............................... 19
7-1-2. DC Power Connector (J2) ....................... 19
7-1-3. DC Power Cable Fabrication ...................... 19
7-2. Signal Interface Connector ............................. 20
7-2-1. Signal Interface Connector (J 1) .................... 20
7-2-2. Signal
Inter~ace Cable Fabrication .................. 20
SECTION 8. MOUNTING AND INSTALLATION .......................... 21
8-1.· Orientation ....................................... 21
8-2. Installation.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
8-3. PCB Component Locations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
SECTION 9. ERROR DETECTION AND CORRECTION ..................... 24
N

SECTION 1
INTRODUCTION
1-1. PURPOSE
This specification provides the information necessary
to interface the OA-D30V Micro Floppydisk drive
to floppy disk controllers, and provides the technical
specifications for reference
in OEM contracts.
1-2. GENERAL DESCRIPTION
The SONY Micro Floppydisk drive represents a
technological break through offering extreme com-
pactness, just 4.0" wide by 2.0" high by 5.1" deep,
and lightweight, just 1.5 Ibs., providing a versatile
data storage component for the OEM Systems de-
signer.
SONY·s leadership in high-density recording tech-
niques, perfected
in video technology, enabled SONY
engineers to develop the Micro Floppydisk, a new
standard, just 3.5".
Yet an unformatted, single side,
double density capacity
of 437.5 K bytes in 135
tracks per inch provides nearly double the capacity
of conventional 5.25"disks.
This disk
is unlike any' you have handled before-
it's floppy,
but not too floppy. A rigid protective
shell provides protection unique
to the Micro Floppy-
disk. Plus a sliding disk guard
to keep out dust, dirt,
fingerprint and
other foreign objects that might
degrade performance plus a metal centering hub,
allowing positioning
to be accomplished with greater
ease and more positive accuracy and over
30,000
interchanges with each diskette.
Driven by a SONY developed direct drive
motor
at a speed of 600 RPM, providing better signal to
noise ratio while transferring data at a fast rate of
500 K bits per second in double density mode, twice
as fast as conventional 5.25" drives.
As drive motor
is a brush less motor, it reduces mechanical and
electrical noise and guarantees
10,000 Motor On
Hour.
-1-
The SONY proprietary read/write and tunnel erase
head developed using video techniques
is positioned
by a precision stepper
motor assembly, providing
fast access while maintaining positioning accuracy.
And high coercivity media provides high data iner-
grity.
The OA-D30V Micro Floppydisk drive
is interface
compatible with conventional
8" floppy disk drives.
Accordingly conventional FDC chips such
as Western
Digital FD1791,
NEC ~PD765 can be used.
Whether your application
is small business systems,
word processing, personal computers
or any related,
you will find the Micro Floppydisk drive offers a
whole new range
of possibilities.
The Micro Floppydisk drive offers the following
features.
* 3.5"floppy disk media with disk guard
* Large capacity .......... 437.5 Kbytes
* High track density ........... 135 TPI
* Long life brushless direct drive motor
* High transfer rate ...... 500Kbps (MFM)

Figure 1-1.

SECTION 2
FUNCTIONAL CHARACTERISTICS
2-1. GENERAL OPERATION
The relationship and interface signals for the internal
functions of the OA-D30V are shown in Figure 2-1.
READ DATA
DRIVE SELECT
WRITE
DATA
WRITE GATE
POWER ON
RESET
WRITE
LOGIC
WRITE HEAD
ERASE HEAD
DRIVE SELECT
WRITE PROTECT CONTROL
Ur-+-+--ERASE CONTROL
HEAD LOAD HEAD LOAD SOLENOID
STEP
CASSETTE IN LED
DIRECTION CASSETTE IN DETECTOR
DRIVE SELECT (2 LINES) IN
USE LAMP
TRACK 00 WRITE PROTECT LED
INDEX CONTROL WRITE PROTECT DETECTOR
LOGIC
READY
PG DETECTOR
WRITE PROTECT MOTOR
ON
TRACK 00 LED
TRACK 00 DETECTOR
STEPPING MOTOR
Figure 2-1. FUNCTIONAL DIAGRAM
2-2. READ/WRITE AND CONTROL
ELECTRONICS
OA-D30V
has following electronic components.
(1) Index Circuits
(2) Head Position Actuator Driver
(3) Head Load Actuator Driver
(4) Read/Write Amplifier and Transition Detector
(5) Write Protect
(6) Drive Ready Detector Circuit
(7) Drive Select Circuits
(8) In Use Lamp Circuits
-3-
2-3. DRIVE MECHANISM
The brushless direct drive motor rotates the sp indle
at 600 rpm. Owing to the long life brush less motor,
the OA-D30V
has no Motor On Control signal that
conventional 5.25" drives have. And for low power
consumption, the drive motor rotates only while
Micro Floppydisk
is inserted. There is no index
hole in the Micro Floppydisk, because the OA-D30V
positions the Disk precisely and Index Pulse is gen-
erated by photo sensor and hall element combination.

2-4. POSITIONING MECHANISM
In order to achieve high accuracy in track positioning,
the head is positioned by a needle screw mechanism.
And a
'steppingmotor (Head Position Actuator)
is controlled through the posicast control method
to do the best performance. The stepping motor
rotates the lead screw clockwise or counterclockwise
in 45° increments. A 45° rotation of the lead screw
moves
the read/write head one track position. When
+5 V and +12 V Power
is on, the Head Positioning
Actuator positions the read/write head at TRACKOO.
And if the head is positioned at TRACK69, STEP IN
command is rejected.
2-5. DISK CHUCKING MECHANISM
A new medium utilizes a centering metal hub which
maintains excellent Track positioning accuracy with-
out causing eccentricity or chucking wear. (See
Figure 2-2.)
CONVENTIONAL
TYPE
NEW TYPE
Figure 2-2. DISK CHUCKING MECHANISM
2-6. READ/WRITE HEAD
The OA-D30V head is a !'lew type of single element
ceramic read/write head with tunnel erase head
to
provide erased areas between data tracks. The head
core
is Mn-Zn single crystal ferrite. The data track
width
is 125 microns and guard band width is 63
microns.
2-7. RECORDING FORMAT
The format of the data recorded on the disk is
totally a function of the host system, and can be
designed around the users application
to best take
advantage
of the total available bits that can be
written
on anyone track. Figure 2-3 shows the
concept of the track format. And Figure 2-4 and
2-5 shows
the typically recommended format.
2-8. FLOPPY DISK CONTROLLER CHIPS
There are some LSI FLOPPY DISK CONTROLLER
(FDC) Chips. Particularly NEC J,LPD765 (Intel 8272)
and NEC
J,LPD745 can format easily. The format
of Figure 2-4 can be obtained by J,LPD765 and that of
Figure 2-5 can be obtained by J,LPD745. SONY
recommends J,LPD745 for more data capacity.
/
/
/ /
/
./
/
/'
./
/
SECTOR
CYLINDER
PHYSICAL:
INDEX~, ~
~W~®(@J ®.-m ~~f-t--L_--f~I.U.l.U.>.~~~-
-4-
L -J :ECTOR 1=:J LSECTOR N L-i
PREAMBLE POSTAMBLE
CD GAP 1
@ 10 FIELD
@GAP 2
@ DATA FIELD
® GAP 3
®GAP 4
SECTOR FORMAT
CD SYNC
@ 10 ADDRESS MARK
@ CYLINDER NUMBER
@ HEAD NUMBER
® RECORD NUMBER
® RECORD LENGTH
(j) CRC
® GAP 2
® SYNC
@ DATA ADDRESS MARK
@ DATA
@ CRC
@ GAP 3
Figure 2-3. TRACK FORMAT

0"1
I
l
I
INDEX ~~---------------------------------~1r-----1L-
SECTOR 1 SECTOR
2--
ID FIELD
DATA FIELD
GAP31 GAP4b
GAP
INDEX
GAP
IDADD
C HI+
ICjC
GAP
DATA
CRC GAP
SYNC SYNC SYNC
DATA
1112
SYNC GAP
4b
4a
MARK
1
MARK
1 2 2
MARK
3
SINGLE l
BYTE (10)
40
6 1 26 6 1 4 2
11
6 1 2 6
DENSITY
1 DATA (16) FF
00
FC
FF 00
FE
**
** FF 00 FBIF8
DATA
** FF 00 FF
-
DOUBLE l
BYTE (10)
80
12 3 1 1 50 12 3 1 1 4 2 22 12
31
1 2 12 I
DENSITY
1 DATA (16) 4E 00
C21 FC
4E
00
A1 J FE
**
**
4E
00
A11~:
DATA
**
4E 00
4E
,
PREAMBLE SECTOR
~~\..~
~OS"(.p.:
Gp.~'?>
GAP4 (MIN.) FM GAP 4 >
11
MFM GAP4
> 2
20
128 73 188 27 232 15
SINGLE 256 73
331
42 73 9
DENSITY (10) 512 73 603 58 640 4
256
146 372 54 524 15
DOUBLE 512 146 658
84
182 9
DENSITY (10) 1024
146 1202 116 1296 4
DATA
GAP3
GAP4
SECTORI
TRACK
SINGLE DENSITY DOUBLE DENSITY
DATA
CLOCK
DATA
CLOCK
INDEX ADDRESS MARK
FC D7 FC
01
ID ADDRESS MARK
FE C7 FE 00
DATA ADDRESS MARK FB C7
FB
00
DELETED DATA ADDRESS MARK
F8 C7 F8
03
GAP FF FF 4E
10
SYNC
00
FF 00 FF
Figure 2-4. pPD765 IBM TYPE STANDARD FORMAT

0>
I
1
1
INDEX~------------------------------------------------------------------------~lt~------~rl~ ____ _
GAP 31 GAP4
GAP1
SINGLE
. IBYTE (10)
16
DENSITY
I DATA
(16) FF
DOUBLE
I BYTE (10)
32
DENSITY
I DATA (16)
4E
PREAMBLE
SECTOR 1
ID FIELD
DATA FIELD
IDADD
CHRIN
IT
DATA
SYNC
MARK
1 2
GAP 2
SYNC
MARK
DATA
6 1 4 2 11
6 1
00
FE
**
**
FF
00
FB F8
DATA
12
3 I 1 4 2
22 12
3 11
00
A1 I FE
** **
4E
00
A11FB
Fa
DATA
SECTOR
~~
0~
128
16
188
27
101
SINGLE
256
16
331
42
130
DENSITY (10)
512
16
603
58
94
256
32
372
54 266
DOUBLE
512
32
658
84
296
DENSITY (10)
1024 32
1202
116 208
DATA
GAP 3 GAP4
Figure 2-5. pPD745 SONY RECOMMENDING FORMAT
(ISO TYPE FORMAT)
SECTOR 2-
*
GAP
GAP
1 2 3
SYNC
4
2 6
**
FF
00
FF
\ ,
2
12
** 4E
00
4E
«:.
~<c'v
f::>-<"~
<?o
16
9
5
16
9
5
SECTOR/
TRACK

SECTION 3
SPECIFICATIONS
3-1. DRIVE PERFORMANCE
Table 3-1 lists performance data for the SONY OA-D30V Micro Floppydisk drive.
TABLE 3-1. PERFORMANCE SPECIFICATIONS
Specification Single Density Double Density
CAPACITY
Unformatted per disk 218.8 Kbytes 437.5 Kbytes
Formatted per disk 161.2 Kbytes 322.5 Kbytes
Burst TRANSFER
RATE
250 Kbits/sec. 500 Kbits/sec.
ACCESS TIME
Track to track 15 msec. 15 msec.
Ave rage * 365 msec. 365 msec.
Settling Time 15 msec. 15 msec.
Head load time 60 msec. 60 msec.
Average latency 50 msec. 50 msec.
FUNCTIONAL
Rotational speed 600
RPM
600 RPM
Recording densit~ (inside track) 3805
BPI
7610 BPI
Track density 135
TPI
135 TPI
Cylinders 70 70
Tracks 70 70
R/W heads 1 1
Encoding method
FM
MFM
HEAT DISSIPATION
Operating mode (Head Load) 7.5 W 7.5 W
Standby mode (Head Unload) 3.3 W 3.3 W
* Average access time =1/3 x (Track Nos.) x (Track to track time) + (Settling Time)
3-2. DIMENSIONAL
DATA
Table 3-2 lists the dimensional data for the Micro
Floppydisk drive.
TABLE 3-2. DIMENSIONAL
DATA
Physical Dimension Value
Height 2.0
in. (51 mm)
Width
4.0 in. (102 mm)
Depth
5.1 in. (130 mm)
Weight
1.5 Ibs (650 g)
-7-
3-3. DC POWER REQUIREMENTS
Table
3-3 lists the DC power requirements for the
drive. The user need only supply
DC power, no
AC operating voltage is required.
TABLE 3-3.
DC POWER REQUIREMENT
Voltage Tolerance Maximum Current
Ripple
+12.0 V DC
±5 % 0.1 Vp-p 0.4 A (typ.)
1.5 A (max.)
+ 5.0 V
DC
±5 % 0.05 Vp-p 0.6 A (typ.)
0.8 A (max.)

3-4. ENVIRONMENTAL CONSIDERATIONS
3-4-1. Reliability and Maintainability
Preventive Maintenance (PM)
Meantime between failures (MTBF)
Meantime
to repair (MTTR)
Component life
Media life
Diskette Interchange
Soft Read Error
Hard Read Error
Seek Error
3-4-2. Environmental
limits
Temperature Operating:
Non-Operating:
Humidity Operating:
Non-Operating:
Vibration Operating:
Non-Operating:
Shock Non-Operating:
Not Required
8000 POH
30 min.
5 years
more
than 1.0 x 10
6 passes/track
30,000 times
1
per 10
9 bits read
1 per
10
12 bits read
1 per 106 seeks
40
0 F
to 115
0 F
(50 C to 45
0
C)
-40
0 F
to 140
0 F
(_40
0 C
to 60
0
C)
(When OA-D30V is set in a box, this temperature means the
ambient temperature of OA-D30V in the box. And Tem-
perature cycling shall
not result in condensation.)
20 % to 80 %relative humidity, with a wet bulb temperature
of 85
0 F (290
C) and no condensation.
5 %
to 95 %relative humidity and no condensation.
The· unit shall perform all read/write operations (no seek)
according
to specifications, with continuous vibration of
less than .5 G (±10 %), from 5 Hz to 100 Hz
(along the x, y, z plane).
The unit when packed for shipment shall withstand ±2.0 G
from 5
Hz to 100 Hz along each of the three mutually per-
pendicular axes.
The unit when unpacked shall withstand 60 G.
-8-

SECTION 4
INTERFACE DESCRIPTION
4-1. HOST SYSTEM INTERFACE
The SONY OA-D30V drive is compatible with
conventional floppy disk controllers. The interface
consists
of 13 signal lines for data, control and hand-
shaking (see Figure 4-1 ).
SELECT 0
SELECT 1
--
DIRTN
--
STEP
WRTDATA
WRTGATE
FLOPPY
DISK
HDLOAD
FLOPPY DISK
CONTROLLER
(RESERVED)
--
INDEX
TRAKOO
WRTPRT
RDDATA
READY
Figure 4-1. SIGNAL INTERFACE DIAGRAM
4-2. INTERFACE CHARACTERISTICS
4-2-1. Input Signal Requirements
The input signals to the
drive unit have the following
requirements at OA-D30V's input terminal:
Logical Zero 0.0 V to +0.8 V
Logical One +2.0 V to +5.25 V
Input Impedance 1000 ohms
-9-
4-2-2. Output Signal Characteristics
The output signals from
following characteristics:
True = Logical Zero
Output Current
False = Logical One
Output Current
the drive unit have the
0.0 V to +0.4 V
40 mA (max.)
+2.4 V to +5.25 V
250 p.A (max.)
4-3. SIGNAL INTERFACE
The drive has 13 interface signals (see Table 6-1 for
pin assignments). Seven signals are input to the drive,
and
six are output. Recommended interface circuitry
is shown in figure 4-2. The seven input signals are
listed below, and are described in 4-3-1.
DRIVE INPUT MNEMONIC
DRIVE SELECT 0 SELECT 0
DRIVE SELECT 1 SELECT 1
DIRECTION SELECT
DIRTN
STEP STEP
HEAD LOAD HDLOAD
WRITE DATA
WRTDATA
WRITE GATE
WRTGATE
The five output signals are listed below, and are
described in 4-3-1.
DRIVE OUTPUT
INDEX
TRACKOO
WRITE PROTECT
READY
READ DATA
MNEMONIC
INDEX
TRKOO
WRTPRT
READY
RDDATA
4-3-1. Input Signal Descriptions
4-3-1-1. Drive Select 0, 1 - Logical 0 on th is line
selects the designated drive for operation.

CONTROLER
DRIVES
DRIVE 0
DRIVE 1
WRITE DATA
D4~38 ~~-5V -~~5V
STEP 1k 1k
100 pF J;. If 100 pF rliT .IT
N-MOS ~
~~~--------------~
DRIVE SELECT
N-MOS
~
~-~-~---~-~1~-1-1-k-~-~-;-~-~---~--~lfk~~~~
N-MOS Jr N-MOS *'
4F~150Q~1 JI
7~ 743~
bo
TRACKOO, WR ITE
PROTECT READY,
READ DATA
INDEX
Figure 4-2. INTERFACE CIRCUITRY
- 10-

4-3-1-2. Direction Select (DI RTN) -This line de-
fines the direction of head movement when the step
line is activated. Logical one on this line defines
the direction as "out", and when the step line is
activated the head will move to the outside of the
disk. Logical zero
on this line defines the direction
as
"in", and when the step line is activated the
head will move
to the center of the disk.
DRIVE SELECT
4-3-1-3. Step -This line causes the read/write
head
to move in the direction defined by the DI RTN
line. The transition from logical one to logical zero
initiates
the stepping motion.
~~--+-----------------~~(---------------------------------
y
DIRECTION IN ---'~I-----6
11 J.lS MIN.
STEP ----.I
15 ms MIN.
Figure 4-3. TRACK ACCESS TIMING
4-3-1-4. Head Load (HDLOAD) -This line causes
the read/write head to contact the disk surface. If
the drive is not selected this line is disabled. When
a disk
is inserted into the drive, the head is momenta-
rily loaded
to properly seat the disk on the spindle.
DRIVE SELECT------
HEAD LOAD------.
LOAD
14---..60 ms MIN.
VAll DREAD DATA ---------"""------"""
Figure 4-4. HEAD LOAD AND UNLOAD TIMING
- 11 -
OUTWARD
200.0 J.lsec MIN.
UNLOAD

4-3-1-5. Write Data (WRTDATA) -This line is used
for data that is to be written on the disk. A transi-
tion from logical
one to logical zero changes the
polarity
of read/write head current and causes a data
bit to be written on the disk. This data line is active
when the WRTGATE
and READY signals are logical
zero, and
the WRTPRT signal is logical one.
DRIVE SELECT-----.
STEP-------.
~----_.t30msMIN.
WRITE GATE-------------....,
WRITE DATA ----------- .......... - ......
Figure 4-5. WRITE INITIATE TIMING
~---4.00 J.LS ± 40 ns---~
150 ns MIN.
1000
ns MAX.
Figure 4-6. WRITE DATA TIMING
4-3-1-6. Write Gate (WRTGATE) -This line defines
an operation
as read or write. Logical zero on this
line enables data
to be written on the disk; logical
one indentifies a read operation. And this line
controls
the tunnel erase head.
WRITE GATE--- __
9---,.....-----1. (~--------f
.... 522.0 J.Ls MIN.
ERASE ON - __ ...... 1.---1
254.0 J.LS MIN.
262.0 J.LS MAX.
J.-~f-----1~ .. 532.0 J.Ls MAX.
------~(~----------------~
Figure 4-7. ERASE ON AND OFF TIMING
- 12-

4-3-2. Output Signal Descriptions
4-3-2-1. Index -This line
is used to indicate a refer-
ence position on a track.
The line is usually a logical
one; it becomes logical zero when the drive senses
the index mark (see Figure 4-8). The trailing edge
of the signal should be used to determine position.
This line becomes logical
one when the drive is not
selected.
----------100 msec ± 2.5 %-------~
150-350 J.1sec
Figure 4-8. INDEX MARK TIMING
4-3-2-2. TrackOO (TRKOO) -This line indicates
that read/write head located at trackOO (the outer-
most track). Logical zero on this line indicates the
head is located at trackOO. Logical one indicates
DIRECTION IN---_ I
IIN~ARD
STEP---- .......U
~ 12 ms MIN ...
......- ....
TRACKOO----------~--------~
the read/write head is not at trackOO. When drive
power is turned on the read/write head positions
itself
at trackOO. When the drive is not selected
this line
is logical one. (See Figure 4-9 and 4-10.)
Figure 4-9. TRACKOO TIMING WHEN STEP IN
IO~TWARD
DIRECTION IN ---~- I
I
STEP-------Io
U
... ..
... 12 ms MIN.....
TRACKOO--------------------~
Figure 4-10. TRACKOO TIMING WHEN STEP OUT
-13 -

4-3-2-3. Write Protect (WRTPRT) -This line indi-
cates a disk is write protected. Logical zero on this
line indicates a write
protected disk is inserted in
the drive. Logical one on this line indicates data
may be written on the disk. If no disk is inserted
in
the drive logical zero appears on this line. If the
drive is not selected this line is logical one.
4-3-2-4. Ready
This line
is logical zero when
a) disk is inserted
and
b) motor is rotating
and
c) drive unit is selected.
At all other times this line is logical one.
4-3-2-5. Read Data (RDDATA)
This line provides unseparated data (data and clock
combined). The line is normally logical one, and
becomes logical zero when
data is read.
DRIVE SELECT--,L._-+ ______________ -i
I (~(---------------------------
).1
STEP------t
~--------------------_i~(---------------------------
:/
WR ITE GA TE--------+------------------.
30 ms MIN.
VALID READ DATA-----...i------I
Figure 4-11. READ INITIATE TIMING
~--4.00 /lS NOM-----.
330 ns ± 50 ns
2.00/ls NOM
Figure 4-12. READ DATA TIMING
- 14-

4-4. INTERFACE TIMING
Figure 4-13
shows the timing relationship for hostl
drive interface signals.
POWEAl~ ________________________________________________________ _
I
I
FLOPPYCISK IN1
I~----------------------------------------------------------
I
CAlVE seLECT~~ ____________________________________________________ _
----t--+j r--0'S ,Ltsee MAX.
READY ~ ,
--+l ' r--- 1.0 sec MAX.
I
~
VALID WRTRRT-"'::~:--
~ ~0.5 ""e MAX.
_l·J r-
~ r--0'S ,usee MAX.
VALID INDEX-....:.,-....:. .........
i ~ 1.000e MAX.
I I
I ,
HDLOAD--~--~--~I_, ____________________________________________ __
II
01 RTN-----------
1
......'
:I
I ~I---------------------------------------------
~ I~ Omsec MIN.
STE?------..:....;...i n n I
U-J-l
~II
15 ~see MIN.! --..! l+--4,:.tsec MAX.
I ' LL .
I ~ ~ aomsecMtN.
I I I J'
I ! I,
WRTDATA---'~--------------------~----~l rlrll
! ~6omseeMIN·--r---~·1 U U U
~14---...;.1-1 sec MIN. -. --+--- •• \: I
VALID RDOA TA---il-----~'------------~----..., I
i! l~
I I --i ~30msecMIN.
I I I
I rt--
60
msee MIN. ~I
I I
~14II1-------1 sec MIN.----~~I
WRTGATE
u
Figure 4·13. HOST SIGNAL INTERFACE TIMING DIAGRAM
-15-