Shugart SA1000, SA1002, SA1004 User Manual

TABLE OF CONTENTS

1.0 Introduction

1.1

General Description

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1.2 Specification Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.2.1

Physical Specifications

1.2.2

Reliability Specifications

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1.2.3 Performance Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Functional Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.2.4

Functional Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.0

2.1

General Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2 Read/Write and

2.3 Drive Mechanism

2.4 Air

Filtration System (Figure

2.5 Positioning Mechanism (Figure

Control Electronics

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1)

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2)

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: . . . . . . .

2.6 Read/Write Heads and Disk(s). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.0 Functional Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.1

Power Sequencing

3.2 Drive

Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.3 Track Accessing

3.4 Head

3.5

Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Read

Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.6 Write Operation

Electrical Interface .

4.0

4.1

Signal Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4.1.1

Control Input Lines

4.1.1.1

4.1.1.2 Direction

4.1.1.3 Step

4.1

DriveSelect1-4

In

.......................................................................

.1.4 Head Select 2° and

4.1.1.5 Write Gate

4.1.1.6 Reduced Write Current Control Output Lines

4.1.2

4.1.2.1 Track

4.1.2.2

000

Index

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4.1.2.3 Ready

4.1.2.4 Write

4.1.2.5 Seek

Fault. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Complete

4.1.3 Data Transfer Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4.1.3.1

4.1.3.2

4.1.3.3 Timing

4.1.4

4.1.5

4.2 Power

4.2.1

4.2.2

Physical Interface

5.0

5.1

MFM Write Data MFM Read Data

Clock Select Status General Timing Requirements

Interface AC DC

J1/P1

Power

Connector

....................................................................

5.2 J2/P2 Connector

5.3 J4/P4 Connector

5.4 J5/P5 Connector

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J.

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'.

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21

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1 2 2 2 3 3

4 4 4 5 5 5 5 7 7 7 7 7 7 8 8 8

10 10 10 11 12 12 12 13 13 13 13 14 14 14 15 15

16 16 17 17 17 17 19 20 20 21 21

6.0 Physical Specifications

7.0 Media Defect and Errors

8.0

SA1

000 Track Format

8.1

Gap Length Calculations

8.1.1

Gap 1

8.1.2 Gap 2

8.1.3 Gap 3

8.1.4 Gap 4

8.2 Write Precompensation

9.0

SA

1000 Jumper Options . . . . . . .

10.0

SA1

000 Unpackaging Instructions. .

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.......

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..

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.. . .........

.. . ........

.

.......

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.

.............

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..

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.

.......

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......

.....

'"

22 24 25 25 25 25 25 25 26 27 28

Figure

LIST

1.

Air Filtration System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.

Positioning

3.

J1

Interface and Power Connection

4.

Control Input Driver/Receiver Combination

5.

Normal Step M o'de

6.

Buffered Step Mode

7.

Head Selection Timing

8.

Control Output Driver/Receiver Combination

9.

Index Timing

10. Data Transfer Line Driver/Receiver Combination

11.

J2

Interface Connection

12.

MFM Read/Write Data Timing

13.

General Control Timing Requirement

14.

Connector Locations

15.

J1

Connector Dimensions

16.

J2

Connector Dimensions

17.

J4

Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

18.

J5

Connector

19.

Rack Mount Physical Dimensions

20.

Standard Mount Physical Dimensions

21.

Track Format

22.

SA1000Controi

23.

SA1000Packaging

Mechanism.

...............................................................

PCB

OF

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ILLUSTRATIONS

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:

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5 6

9 10 11 11 12 13 13 14 15

15 16 19 20 20 21 21 22 23 26 27

28

1.

Head Select

2.

AC

Power Requirements

3.

DC

Requirements

4.

Write Precompensation

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.,

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TABLES

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12 18 18 26

1.0 INTRODUCTION

1.1

GENERAL DESCRIPTION

The Shugart Model 1 000 series disk drive 8"

disks as storage media. Each disk surface employs one movable head to service 256 data tracks. The

two models of the

SA 1002 provides 5 megabytes accessed by 2 movable heads and the SA 1004 provides 10 megabytes ac-

cessed by 4 movable heads. Low cost and unit reliability are achieved through the use

simplicity of mechanical construction and electronic controls

the life of the drive.

Mechanical and contamination protection for the head, actuator and disks are provided bv tant plastic and aluminum enclosure. A self contained recirculatin'g system supplies clean air through a micron filter. Another absolute filter allows pressure equalization with ambient air.

The optional coding/decoding, write precompensation, a crystal write oscillator and address mark writing and detection. These functions are also provided by the optional

SA

The is designed to fit into the same physical space as the

Key Features:

1000 fixed disk drive's interface

• Storage Capacity Winchester design reliability.

•

SA1

000 series are the 1002 and the 1004 with single and double platters respectively. The

SA

1200 Data Separator

of

5.33 or 10.67megabytes.

IS

a random access storage device with one or two non-removable

of

a unique band actuator design. The inherent

allows maintenance free operation throughout

an

impact resis-

PCB

or equivalent circuitry is necessary to provide MFM en-

SA

1400 controller.

is

similar* to the Shugart

8"

floppies.

family of floppy disk drives. The SA 1000

0.3

• Same physical size and identical mounting configuration as the

• Uses the same D.C. voltages as the SA800/850 floppies.

• Proprietary Fas Flex III band actuator.

• 4.34 Mbits/second transfer rate.

• Simple floppy like interface.

*Existing floppy

controllers are not compatible with the

SA

1000 due to differences

SABOO/B50

floppies.

in

the data transfer rates.

1

1.2 Specification Summary

1.2.1 Physical Specifications

Envi

ron

mental Limits

Ambient Temperature

Relative Humidity = Maximum Wet Bulb =

AC

Power Requirements

50/60

Hz ± O.5Hz 100/115 200/230

DC

Voltage Requirements

VAC

Installations

VAC

Installations

+ 24VDC ± 10

(O.2A

typical steady state, non stepping)

+ 5VDC ±

typical non-stepping)

-5VDC±5% (-7

Mechanical

Height

Width = Depth = Weight =

Heat Dissipation

1.2.2 Reliability Specifications

=

5%

2.OA

Dimensions

Rack Mount

4.62

8.55

14.25 17

= 150 Watts

=

%

2.BA typical during stepping typical during stepping (3.6A

to -16VDC optional) 0.2A typical

in.

(117.3mm)

in.

(217.2mm)

in.

(362.0mm)

Ibs.

(7.

7Kg)

(511

50°

to 115°F (10° to

BO/o

to

BO%

7Bo

non-condensing

= 90-127V at

= 1

BO-253V

Standard Mount

4.62 in. (117.3mm)

9.50 in. (241.3mm)

14.25 in. (362.0mm) 17

STU/Hr) Max.

1.1

at 0.6A typical

Ibs. (7.7Kg)

46°C)

A typical

MTBF: PM: MTTR: Component Life: 5 years

Error Rates:

B,OOO

POH

typical usage

None Required

30

minutes

Soft Read Errors: Hard Read Errors: Seek Errors:

1 per 1 per 1 per

10

bits read

12

10

bits read

106 seeks

2

1.2.3 Performance Specifications

Capacity

Unformatted

Per Drive Per Surface 2.67 Mbytes 2.67 Mbytes Per

Track

Formatted

Per Drive Per Surface Per Track Per Sector 256 bytes

Secto rslT rack Transfer Rate 4.34 Mbits/sec Access Time

Track to Track 19 msec Average Maximum 150 msec 150 msec

Average Latency 9.6 msec

SA1002

5.33 Mbytes

10.4 Kbytes

4.2 Mbytes

2.1

Mbytes

8.2 Kbytes 32

70 msec

SA1004

10.67 Mbytes

10.4 Kbytes

8.4 Mbytes

2.1

Mbytes

8.2 Kbytes 256 bytes

32

4.34 Mbits/sec 19 msec

70

msec ,

9.6 msec

1.2.4 Functional Specifications

Rotational Speed 3125 rpm

Recording Density 6270 bpi

Flux Density 6270 fci Track Density 172 tpi Cylinders. Tracks 512

256

R/W Heads 2

Disks 1 2

3125

6270 bpi 6270 fci

172 tpi

256

1024

4

rpm

3

2.0 FUNCTIONAL CHARACTERISTICS

2.1

GENERAL OPERATION

The SA 1000 fixed disk drive consists ing mechanism, media, and air

1.

Interpret and generate control signals.

2.

Position the heads over the selected track.

3.

Read and Write data.

4.

Provide a contamination free environment (Class 100 or better).

of

read/write and control electronics, read/write heads,

filtration system. These components perform the following functions:

2.2 READ/WRITE AND CONTROL ELECTRONICS

The standard 1 . I ndex

2. Head Position

3. Read/Write

4.

Drive (Ready) up to Speed Circuit

5.

Drive Select

6.

Write Fault Detection Circuit

electronics

Detector

Amplifiers

Circuit

are packaged on a single printed

Ci

rcuit

Actuator

Drivers

circuit

track

board containing the following

position-

circuits:*

7.

Read/Write Head Select Circuit

8.

Step Buffers with Ramped Stepper Circuit

9.

Track 000

* Early units

indicator

may

have two printed

circuit

boards.

4

2.3 Drive Mechanism

The

AC

drive motor rotates the spindle at 3125

RPM

accommodated by changing the drive pulley and

2.4

Air

Filtration

System (Figure

1)

through a belt-drive system. Either 50 or 60 Hz power is

belt.

The disk(s)" and read/write heads are fully enclosed with

an

absolute filter which maintains a clean environment. A separate absolute breather filter permits

in

a module using

an

integral recirculating air system

pressure equalization with the ambient air without contamination.

2.5 Positioning Mechanism (Figure

The read/write heads are mounted

IIITM

actuator. A stepper motor is used to precisely position the carriage assembly utilizing a unique metal

2)

on

a ball bearing supported carriage which is positioned by the Fasflex

band/capstan concept.

2.6 Read/Write Heads and Disk(s)

The recording media consists of a lubricated thin magnetic oxide coating on a 200mm diameter aluminum substrate. This coating formulation, together with the low load force/low mass Winchester type flying heads, permit

reliable contact start/stop operation.

Data on each disk surface is read by one read/write head, each of which accesses 256 tracks. The drive is available

in

two basic configurations: one disk with two read/write heads, or two disks with four read/write

heads.

B~rometric

Pressure Compensation

Absolute Filter

Low Pressure

Area

Figure 1 Air Filtration System

5

Air Flow

Path

High Pressure

Area

Circulating Air Absolute

Filter

Stepper Motor

Ball Bearing

Carriage Support

Figure 2 Positioning Mechanism

6

3.0 FUNCTIONAL OPERATIONS

3.1

POWER SEQUENCING

Since the SA1000 has a speed sense circuit'that prevents stepping until the disk is rotating at the proper speed, no power the disk

is recalibrate itself read/write functions can now begin. Refer to Figure

up

to

on

sequence

95%

of its normal rotational speed. At

to

TKOOO.

is

required. A

After a 18 msec head settle time,

READY

signal will be presented to the controller interface once

READY

time, after

SEEK

COMPLETE will go true. Normal seek and

an

initial power up, the drive will

3.

3.2 DRIVE SELECTION

Drive selection occurs when one of the Drive Select lines will respond to the activated Drive Select line.

3.3 TRACK ACCESSING

Read/Write Head positioning a.

Deactivating Write Gate.

b.

Activating the appropriate Drive Select Line.

c.

Being

in

the

READY

d.

Selecting the appropriate Direction.

e.

Pulsing the Step Line.

at

Stepping can occur ed

at

the rate of incoming step pulses.

either the Normal or Buffered rate. During Normal Stepping, the heads are reposition-

at a high rate and are buffered into counters. When

is

accomplished

condition with

In

by:

SEEK

COMPLETE

the case of Buffered Stepping, incoming step pulses are received

all of the steps have been received, they are issued at a

ramped stepping rate, to the stepper drivers.

pulse will cause the heads to move either 1 track

Each

In

tion result

line. A true

in

an

outward seek toward

on

the Direction

In

Line will cause

TKOOO.

in

an

3.4 HEAD SELECTION

is

activated. Only the disk appropriately jumpered

true.

or 1 track out, depending

inward seek; a false

on

the level of the Direc-

on

the Direction

In

Line will

Any of the 4 possible heads can lines.

3.5 READ OPERATION

Reading data from the disk a.

Deactivating the Write Gate Line.

b.

Activating the appropriate Drive Select Line.

c.

Assuring that the drive

d.

Selecting the appropriate head.

is

be

selected

accomplished

Ready.

by

placing that head's binary address

by:

7

on

the two Head Select

3.6 WRITE OPERATION

Writing data onto the disk a.

Activating the appropriate Drive Select Line.

b.

Assuring that the Drive is Ready.

c.

Clearing any write fault conditions if they exist, by reselecting the drive.

d.

Selecting the proper head.

e.

Activating Write Gate and placing data

4.0 ELECTRICAL INTERFACE

The

interface of the

1.

Signal Interface

2.

DC

Power

3.

AC

Power

The

following sections provide the electrical definition for each line.

4.1

SIGNAL INTERFACE

The

signal interface consists of three categories:

is

accomplished

SA

1000 can be divided into three categories:

by:

on

the Write Data line.

1.

Control Input lines

2.

Control Output lines

3.

Data Transfer lines

in

All control lines are digital disk controller (output)

via the interface connector J1/P1.

nature and either provide signals to the drive (input) or provide signals to the

The

they provide data and clocking, either to or from the drive,

NOTE: Refer to Figure

lines to carry

are uncommitted for the not

be

SA

used as alternate signals if a controller having

3.

Those signal lines marked SPARE are uncommitted. They

1000 signals

SA1000, but are assigned for the

if

the user prefers to do his own modification. Those

data transfer signals are differential

via J2/P2.

may

be used as alternate

SASOO/SSO.

an

SA800/850 interface

Therefore, these signals should

signal

is

lines

used.

in

nature,

marked NA

8

DISK

CONTROLLER

FLAT RIBBON

OR

TWISTED PAIR

20

FT.

MAX

.,

TWISTED

PAJR

LOGIC

GROUND

FRAME GROUND

DISK CONTROLLER

--

-

--

-

--

-

-REDUCED WRITE CURRENT.,

SPARE

-SEEK COMPLETE

NA

-HEAD

SELECT

NA

-HEAD SELECT

-INDEX

-READY

NA

-DRIVE SELECT 1

-DRIVE SELECT 2

-DRIVE SELECT 3

-DRIVE SELECT 4

-DIRECTION

-STEP

NA

WRITE

GATE

-TRACK 000

-WRITE FAULT

NA

+5V

DC

-5VDC (-7V

to

-16VDC OPT)

+ 24V

DC

ACINPUT FRAME GROUND

ACINPUT

1

..

2

4

6

8

10

12

2°

21

IN

...

-

...

~

..

~

...

--

..

.~

~

--

~

-

14

16

18

20

22

24

26

28

30

32

34

36

38

40

42

44

46

48

5

4

1

1 2

3

50

AC

5

7

9

11

13

15

17

19

21

23

25

27

29

31

33

35

37

39

41

43

45

47

49

6

3

2

MOTOR GROUND

~

-

DRIVE

LOGIC GROUND

~51P5

-

SINGLE

SA1000 DRIVE

J1/P1

WIRE

STRAP

J4/P4

Figure 3

J1

Interface and Power Connection

9

4.1.1 CONTROL INPUT LINES

The control input signals are of two types: those intended to be mutliplexed those intended to control the multiplexing. The control input signals to be mutliplexed are IN,

HEAD SELECT 20 and

do the multiplexing

is

DRIVE

21,

WRITE

SELECT

GATE

and REDUCED WRITE CURRENT. The signal which

1,

DRIVE

SELECT

2,

DRIVE SELECT

in

a multiple drive system and

STEP,

DIRECTION

is

intended to

3,

DRIVE SELECT

4.

The input lines have the following electrical specifications. Refer to Figure 4 for the recommended circuit.

+5

V

20ft (MAX.)

330n

Figure 4 Control Input Driver/Receiver Combination

The 7438 has the following characteristics:

=

True

O.OVDC

False = 2.5VDC to 5.25 VDC @ lin = 250

Only 1 drive drives. A

to

O.4VDC

in

the system should be terminated, if floppy disks are daisy chained together with SA1000

SA

1000 should be physically located at the end

@ lin = 40 ma(max)

Ita

(open)

of

the cable and terminated at

IC

location

BC.

A 220/3300 resistor pack, located at

IC

location

4.1.1.1 DRIVE SELECT 1·4

DRIVE

SELECT,

when logically true, connects the drive to the control lines. Only one DRIVE SELECT line

may be active at a time.

Jumper options

DS1,

DS2, DS3, and

DS4

are used to select which drive select line will activate the interface

for that unique drive.

4.1.1.2 DIRECTION IN

This signal defines the direction

of

motion of the read/write heads when the

cuit or logical false, defines the direction as

head will move away from

is

of motion

defined as

the

center

of

the disk. If the input is shorted to ground, or logical true, the direction

"in"

and if a pulse is applied to the

the center of the disk.

"out"

8C,

provides input line termination.

and if a pulse

STEP

is

applied to the

line, the read/write heads will move towards

STEP

line is pulsed.

STEP

line, the read/write

An

open cir-

10

4.1.1.3 STEP

This line causes the read/write heads to move tion is initiated at each least

200 ns before the trailing edge of the step pulse. Stepping can be performed

Buffered mode:

-DIRECTION

logical true to false transition. Any change

~

W!!/f!!fIl/f!lI~~~rm

~-------~~~~------------------~SS~--------

J

-STEP

l

------.U

--1

-SEEK

COMPLETE

Figure 5 Normal Step Mode

• Normal Step Modepulses. The minimum time between successive steps

3.0j.ts.

Refer to Figure

• Buffered Step Modecounter. After the last step pulse, the read/write heads will begin stepping the desired number of cylinders and tle

on

the cylinder. This mode

pulses is the less than

In

this mode, the read/write heads will move at the rate of the incoming step

5.

In

this mode, the step pulses are received at a high rate and buffered into a

SEEK

COMPLETE (Refer to Section 4.1.2.5) will go true after the read/write heads set-

of

operation is

200j.tsec.

~

200ns MIN.

I

t-3.0I's

j.----1.5ms

~

500ns

I

in

the direction

MIN. I

TYP

automatically

as

defined by the DIRECTION

in

the DIRECTION

MIN.~

.....

_-\~""'~

IN

line must be made at

in

either the Normal or

____

U

18ms

TYP

~

is

1 .5ms, with a minimum pulse width of

selected

when the time between step

~

Sr-,~_

IN

line. The mo-

_

100 ns after the last step pulse has been sent to the drive, the DRIVE SELECT line may be dropped

and a different drive selected.

The maximum time between steps is

6).

NOTE: A high pitched noise may be present if

data cable disconnected (no timing clock signal). It's the stepper motor trying to return to track zero with avoided.

no

step pulses present. While this will not damage the drive, this condition should be

-----.-,

DIRECTION

-

STEP

--1

-

SEEK

COMPLETE

-

DRIVE

SELECT

X

----------------------------~

200j.ts

with a minimum pulse width of

AC

and

-~~~~~~~

~

500ns

TYP

I

Figure 6 Buffered

DC

power are applied to

...,

~

200ns MIN.

I

~----~s~----------

J.-150ms

I

-..t

~200ns

J

Step Mode

3.0j.ts.

(Refer to Figure

an

SA

1000 with the

MAX.

~

SS

MIN"

SS~----

I

NOTES:

1.

Step pulses with periods between

guaranteed if this timing requirement is violated. ,

2.

A 220/3300 resistor pack,located at

200j.ts

and 1.5ms are not permitted. Seek accuracy is not

IC

location

11

8C,

allows for Step line termination.

4.1.1.4 HEAD SELECT 2° and

21

These two lines HEAD

SELECT

Table 1 shows the HEAD

rrovide

for the selection of each individual read/write head

2 is the least significant line. When all HEAD

SELECT

Figure 7 for the timing sequences). A

220/330n resistor pack, located at

HEAD

SELECT

2°

1 1 0 0 1 0 0

LINE

21

1

Table 1 Head Select

4.1.1.5

The active state of this tive state of this

WRITE GATE

signal (logical zero level) enables

Signal (logical one level) enables data to

pulses to reposition the head arm.

in

a binary coded sequence.

SELECT

lines are false, head 0 will be selected.

SEQUENCE and model variations for the HEAD

IC

location

8C,

HEAD#

SA1002

allows for input line termination.

SELECTED

0 0

1 1

-

(1

= False, 0 = True)

WRITE

DATA to

be

transferred from the drive and enables

HEAD#

SA1004

be

written onto the disk. The inac-

SELECT

SELECTED

2

3

lines. (Refer to

STEP

HEADS SWITCHED

READ DATA VALID

~:~~~~::E

~:8~

CONTROLLER)

-.j

~

20l's

MAX.

~

____

~I

---+----------~

----~I----------

.......

~

460ns

,--,L..

Figure 7 Head Selection Timing

220/330n resistor pack, located at

A

IC

location

8C,

allows for termination of this line.

4.1.1.6 REDUCED WRITE CURRENT

When this interface 128 through 255). When this

signal

is

low (true) the lower value of Write Current is selected (for writing on cylinders

Signal is high (false), the higher value of Write Current

cylinders 0 through 127). A 220/330n resistor pack, located at

I

~

~201'S

MAX.

t7Ax

________

Ie

location

__

8C,

allows for line termination.

is

selected (for writing

on

12

4.1.2 CONTROL OUTPUT LINES

The control output signals are driven with 40 ma at

logical zero (true), with a maximum voltage of

at logical one (false) the driver transistor

an

open collector output stage capable of sinking a maximum of

is

off and the collector cut off current

OAV

measured

at

the driver. When the line driver

is

a maximum of 250

microamperes. All

J1

output lines are enabled by their respective

DRIVE

SELECT

line.

Figure 8 shows the recommended control signal driver/receiver combination.

+5

V

20ft (MAX.)

330n

Figure 8 Control Output Driver/Receiver Combination

4.1.2.1 TRACK 000

This interface signal indicates a true state (logical zero) only when the selected drive's read/write heads are

is

at track zero (the outermost data track) and the access circuitry stepper motor.

This)signal

is

false (logical

one)

when the selected drive's read/write head

driving current through phase one of the

is

not at track zero.

is

4.1.2.2 INDEX

The

drive provides this interface signal once each revolution (19.2ms) to indicate the beginning of the track.

Normally, this signal is a logical one and makes the transition to logical zero for a period of approximately

OILS

once each revolution. Refer to Figure

1

INDEX

~

1

..

9.

________________ r-1 ___ __

~10I"STYP

19.2ms NOM. •

I

Figure 9 Index Timing

4.1.2.3 READY

This interface signal when true (logical zero), together with

ready to read, write, or seek and that the signals are valid. When this line

is

the disk and seeking

will

be

Ready

power

on

true after the drive

is

5 seconds.

inhibited at the drive.

is

95 ± 2%

up

to speed. The typical time for READY to become true after

SEEK

COMPLETE,

is

false (logical one), all writing to

indicates that the drive

is

13

4.1.2.4 WRITE FAULT

This signal when active (logical zero) is used to indicate that a condition exists

improper writing

•

WRITE

on

the disk. A

CURRENT

WRITE

in

the head without

FAULT occurs whenever one of two conditions occur:

WRITE

GATE

active.

at

the drive that could cause

• Multiple heads selected.

To

reset the

WRITE

FAULT line, deselect the drive for at least 500

ns.

4.1.2.5 SEEK COMPLETE

SEEK

COMPLETE will

completion of a seek. Reading or writing should not be attempted until

• A recalibration sequence

go

true (logical zero) when the read/write heads have settled

SEEK

COMPLETE will go false

is

initiated (by the drive logic) at power

in

two cases:

on

if the read/write heads are not

on

COMPLETE

over track zero.

• 500

NS

typical, after the leading edge of a

STEP

pulse (or the first of a series of step pulses).

4.1.3 DATA TRANSFER LINES

lines associated with the transfer of data between the drive and the host are differential

All may not and TIMING CLOCK and are provided at the J2/P2 connectors driver/receiver combination.

be

multiplexed. These three pairs of balanced signals are: MFM

WRITE

on

all drives. Figure 10 illustrates the

DATA,

the final track at the

is

true.

in

nature and

MFM

READ

DATA,

HIGH

TRUE

Figure

FLAT CABLE

r*-_....;;.20;;.;.;ft~M;;..;;AX...;;...

10

Data Transfer Line Driver/Receiver Combination

+SIGNAL

-SIGNAL

_.

_,""*,

5Hl

x 2

>-_

75107B

HIGH

TRUE

14

HOST

FLAT CABLE

OR TWISTED

PAIR

20

FT

MAX

..

--

..

.:

-

-DRIVE GND SPARE GND

SPARE

GND SPARE GND

+

TIMING

-TIMING GND

GND

+

MFM

-MFM GND GND

+

MFM

-MFM GND GND

SELECTED

ClK ClK

WRITE DATA WRITE DATA

READ DATA READ DATA

..

-

~

-

..

-

..

~

1

:3

5

7

9

10

13 14

17

18

11

12

15 16

19

20

2

DRIVE

4

J2/P2

6

8

-==

-

Figure

11

J2

Interface

Connection

-==-

-

4.1.3.1 MFM WRITE DATA

This pair of signals ,defines the transitions (bits) to be written on the disk. + MFM WRITE DATA going more

positive than -MFM WRITE GATE is active. This signal must be driven to an inactive state than -MFM WRITE DATA.

WRITE DATA) by the host system when in the read mode. Figure 12 shows the timing for MFM

WRITE DATA will cause a flux reversal on the track under the selected head providing

(+

MFM

WRITE DATA

more

negative

4.1.3.2 MFM READ DATA

The data recovered by reading a pre-recorded

of MFM READ DATA lines. This transition of the READ

DATA line represents a flux reversal on the track of the selected head while WRITE GATE is inactive.

to

Refer

Figure 12.

-

DRIVE

SELECT

track

is transmitted to the host system via the differential pair

+ MFM READ DATA line going more positive than -MFM

~~---------------------------------

-HEADSELEGT

+

MFM

VALID

READ

DATA

20ILs

---,~

MAX.

____________________________________________

--1

~,

-.j

~ 50ns

TYP

__

-WRITE

+MFM

WRITE

GATE

DATA

--------------------------~~----------------

----~I·-------2-0-IL-S-M-A-X·------·~1

!

I I

460ns

MAX·

.... I

~

--.j

~

BIT

CELL

= 230ns

Figure 12 MFM Read/Write Data Timing

TYP

-..J

j.-

15

-1

Pj-----------------

50~S

MIN. to 150ns

MAX.

4.1.3.3 TIMING CLOCK

This is a differential pair of clock signals (provided by the host) having a

3.6866 write data. the host for the poses.

4.1.4 SELECT STATUS

A status line The

active plug

p,s ± .1

DRIVE

only when the drive

in

the vicintiy of

-DISK

% period.

Phase relationship between TIMING CLOCK and MFM

SA1

000 interface. The TIMING CLOCK

is

provided at the J2/P2 connector to inform the host system of the selection status of the drive.

SELECTED

AC POWER ON

DC

POWER ON

95%

SPEED*_*

The

frequency of this clock

line

is

driven by a

is

programmed

J1,

and that DRIVE

---1

---.J

H5SEC.

___

--.

is

TTL

open collector driven

as

drive X

SELECT

TYP

(X

= 1 ,

X line at

exactly 1/16 the bit frequency for the standarized

WRITE

used by the drive logic for clocking and timing pur-

as

shown

2,

3 and

4)

by proper placement of the shorting

J1/P1

is activated by the host system.

50% (nominal) duty cycle and a

DATA need not be maintained by

in

Figure

8.

This signal will go

-READY*

-...J

~1ms

-TKOOO

-----

....

1

~.

___________________________

--..J

COMPLETE

-SEEK

I

.....

.....--------2 MIN. NOM. *

CONTROL OUTPUTS VALID •

*The drive will bring Ready speed. thermal expansion to stabilize.

* * Disk up to speed signal does not connect to the drive interface cable.

_______________________________________

active

It is now safe to seek the drive but an additional 2

Figure 13 General Control Timing Requirement

TYP

I~

5.1

SEC.

MAX

-------i~~1

as soon as the disk is rotating at

minutes

should be allowed for

~I~

95%

__

----

of normal

16

4.1.5 GENERAL TIMING REQUIREMENTS

The timing diagram

restrictions) for proper operation of the drive. Note that a

recal sequence to function, the following conditions must be met:

• TIMING CLOCK

•

• Spindle

POWER INTERFACE

4.2

The

SA

DC

power is used for the electronics and the stepper motor.

4.2.1 AC

The

AC

power requirements.

4.2.2 DC

DC

power to the

and their specifications along with their J5/P5 pin designations, are outlined

recalibrate to track zero sequence

STEP

Input at

will not occur until disk

tion

1000 requires both

POWER

power

POWER

as

shown

is

J1/P1

is

spinning at regular speed (if

is

via the connector J4 mounted at the center rear of the drive. Table 2 shows a listing of the

_drive

is

in

Figure 13 shows the necessary sequence of events (with associated timing

is

initiated automatically at every

supplied to the drive (via J2/P2).

is held inactive.

AC

and

DC

is

up to speed).

AC

and

DC

power for operation. The

via connector J5/P5 located

on

are switched

AC

the solder side of the

on

power

at the same time, stepping ac-

is

used for the drive motor and the

PCB.

in

DC

power

Table

on.

The three

3.

For this auto-

DC

voltages

NOTE: The

with a ground strap tion of these grounds, remove the strap.

SA

1

abo

is

shipped with

located

DC

(base casting) and

on

the drive motor. If the system configuration requires the separa-

AC

ground (drive motor) connected together

17

60HZ

50HZ

CONN

MAX

INRUSH

CURRENT

MAX

RUN

FREO

TOl

P4

1 2 3

(3

SEC)

CURRENT

110V

(STANDARD)

90-127V 180-253V

FRAME

90-127V RTN 180-253V

2.6A

1.0A

GND

± 0.5

203/230V

FRAME

1.1/1.25A

0.5A

HZ

Table 2 AC Power Requirements

GND

110V

90-127V FRAME 90-127V

RETURN

2.6A 1.2A

1.1A 0.6A

GND

± 0.5

180-253V FRAME 180-253V

-

HZ

220V

GND

P5

CONNECTOR

+24

± 2.4V

P-P

1V.

MAX.

Ripple

+5

± O.25V

P-P

50mV MAX. Ripple

(-7

TO -16V OPT)

-5 ± O.25V 50mV

P-P

MAX. Ripple

STEAD Y STATE

MAX.

TYP

O.25A O.20A

4.1A

O.25A

Table

3 DC Requirements

3.6A 2.5A

O.20A O.25A

CURRENT

STEPPING

MAX. TYP

3.3A 2.8A

2.0A

O.20A

-

18

5.0 PHYSICAL INTERFACE

The electrical interface between the J1,

provides control signals for the drive; the second connector,

read/write

signals; the third connector,

power and frame ground. Refer to Figure

SA

1000 and the host system

J5,

provides

14

for the connector locations.

DC

is

via four connectors. The first connector,

J2,

provides for the radial connection of the

power; and the fourth connector,

J4,

provides

AC

Figure

14

Connector

19

Locations

5.1

J1/P1 CONNECTOR

Connection to

Figure

of the

PCB

recommended mating connector for

15.

PCB

connector closest to the

J1

The pins are numbered 1 through

is through a

and odd pins located

50

J2

t

.4 00 ± .010

on

connector and

-.j~

2-r-

~

--11

I·

BOARD

THICKNESS

.062± .007

Figure 15

5.2 J2/P2 CONNECTOR

Connection to numbered pins Scotchflex ribbon connector the dimensions for the connector.

J2

is through a

located

20

on

the component side

3461-0001. A key slot

PCB

edge connector.

50

the non-component side of the

P1

.036 ± .004

with the even numbered pins located

is

labeled. A Key Slot

is

Scotchflex ribbon connector

T

.450r

.010

--j

f--.050 NOM.

-.050

NOM.

PCB

edge connector.

.100NOM.-

2.575± .010

J1

Connector Dimensions

of

the

The

dimensions for this connector are shown

I

,

~

The

pins are numbered 1 through

PCB.

The

recommended mating connector for

is

provided between pins 4 and

on

PCB.

Pin 2 is

is

provided between pins 4 and

3415-0001.

50

'--j

NOM.

f-.06~

the component side

located

-I

on

the end of the

20

with the even

P2

6.

Figure 16 shows

6.

in

The

is a

--r

t

400,

~

BOARD

.062

2

--.,,--

.036 ± .004 !

----

.010

-r-

1

T

.450±

.~

.010

·1

:',

I

.,

I --j

f---'O~ON.

---1

f---.050

-

THICKNESS

..

007

Figure 16 J2 Connector Dimensions

OM.~.II

NOM. . --I I .100 NOM.

1.075'

.010

20

I

!

~

.063 NOM.

20

5.3 J4/P4 CON N ECTOR

AC

power and frame ground are interfaced through a 3 pin connector,

J4

is

The AMP part number for

17.

Figure 350536-1.

The recommended mating connector,

1-480701-0 with pins AMP

P4,

is AMP socket

J4,

located

350687-1 and 350654-1 (ground pin), refer to

1-480700-0 with AMP pins

on

the end of the drive.

5.4 J5/P5 CONNECTOR

The

DC

power connector, J5,.is a 6 pin AMP Mate-N-Lok connector

component side of the

utilizing

AMP pins

Control

60619-1. The

PCB.

Figure 17

The

recommended mating connector,

J5

pins are labeled

Figure 18

®

@

®

J4

Connector

on

CD

-

@

®

J5

Connector

the connector. Refer to Figure

1-380999-0, mounted

P5,

is

an

AMP

on

1-480270-0

18.

the non-

21

6.0 PHYSICAL SPECIFICATIONS

This section describes the mechanical dimensions and mounting recommendations for the

Figures 19 and

The

SA

1000

• Vertical -

• Horizontal -

IMPORTANT NOTE: Spindle lock shown

transported. Damage to the magnetic heads, disks, or both may occur if ment.

1r

iT

20

for the dimensions.

is

capable of being mounted

on

either side

PCB

Up.

FRONT COVER OUTLINE

J-

0-

t

2.42

+

t

208

t

80~1

I

'0

in

either one of the following positions:

in

figures

8-32 U NC-2B

~~UNTING

0

..

HOLES

0

8.00

19 & 20

(12

pis)

0

-9-

0-

NEW STYLE

must

-

D

be

installed whenever drive

spindle

PCB

is

not locked during ship-

I

f

4.50 MAX

~

SA1

000. Refer to

is

being

DRIVE MOTOR PULLEY

.25~14"

.• 4 100

7.469

-II

....... ' --++-<t-

DRIVE MOTOR

LOCK

"-

3.00 DIA

THIS

AREA

TO

BE

FOR

ACCESS

OLD STYLE

THRU

___

-----14.00

~3

50----+\

/.

I

~~'38

LEFT OPEN

TO

LOCK

DIA

-~-~~

~

DRIVE MOTOR PULLEY

T

8.55

Figure 19 Rack Mount Physical Dimensions

22

FRONT COVER OUTLINE

8-32 U NC-2B *

MOUNTING HOLES

.....

-----

....

--------1~.aa--------I~

8.0.0.

-----+I

(20

NEW

pis)

PCB

STYLE

,DRIVE MOTOR PULLEY

,.251

....

1.0.0.

.~4 I ~3

9l_

DRIVE MOTOR

LOCK

"'-

3.0.0. AREA

THIS

LEFT

OPEN

TO

SPINDLE

4--------14.0.0.

I"

5Q.---.t

//DRIVE

~l~

DIATHRU

t

~

DRIVE MOTOR PULLEY

DIA

TO

BE

FOR

ACCESS

LOCK

OLD

STYLE

MOTOR LOCK.

T

9.14

Figure 20 Standard Mount Physical Dimensions

23

7.0 MEDIA DEFECT & ERRORS Introduction

In

high density digital recording storage systems it is necessary to increase the reliability or improve the operational performance the predominant error pattern sent bits) or shifted bits from their These errors are due ror occurrence. The error rate cuits, head and pOSitioning of actuator.

by

providing

to defects

an

error detection and correction scheme. For disk storage systems,

is

a burst of errors occurring

nominal position more than the data separator can tolerate them to shift.

in

the media

is

dependent upon noise and phase characterisitics of media, Read/Write cir-

as

well

as

in

one or more tracks which are drop outs (ab-

signal to noise ratio contributing to probability of er-

What Is The Definition Of

An

error

is

any discrepancy between recovered data and true correct recorded data. There can be bit or a missing bit, i.e., a cari be system.

If

classified into soft or hard errors. Soft errors are generally related to signal to noise ratio of the

an

error

is

repeatable with a high probability, it

An

"zero"

Error?

can be transformed into

is

due to media defect ahd

"one"

or a

"one"can

How Will Shugart Find the Errors?

The errors will be identified prior to shipment and information incorporated

user to skip those defective which exercises the drive

of each bit recorded

on

locations per his system capability. Shugart has a unique media test system

in

extreme marginal conditions and measures the amplitude and phase distortion

the disk storage.

Error Reporting

A map will cylinder and head address. Additionally, cylinder 000

be

provided with each drive showing defective bytes as a location from index identified by

is

guaranteed to

be

Error Acceptance Criteria

There will be no more than

defects.

ple

single defect is defined

A than 2 bytes

long, or a single error

12

tracks with defects per head of which no more than 4 tracks will contain mUlti-

as

an

error less than 2 bytes long. A multiple defect is defined

in

several sectors.

an

be

changed to"zero".Errors

is

termed a hard error.

in

a usable format to enable the

error free.

as

an

error greater

extra

24

8.0 SA1000 TRACK FORMAT

The

purpose of a format is to organize a data track into smaller, sequentially numbered, blocks of data called sectors. The by

a prewritten identification (1.0.) field ·which contains the physical sector address, plus cylinder and head

information. The

The

soft sectored format is a slightly modified version of the I.B.M. system 34 double density, which

monly used on 8 inch floppy disk drives. The encoding method used here

SA

1000 format is a soft sectored type which means that the beginning of each sector is defined

1.0. field is then followed by a user data field.

is

modified frequency modulation

(MFM).

In

the example shown (Figure

in

bytes The

length.

beginnings of both the I.D. field and the data field are flagged by unique characters called address

21),

each track is divided into

32

sectors. Each sector has a data field of 256

marks. An

address mark is 2 bytes

an

"FE"

pattern which

in

length. The first byte is always

is

the pattern used to define

an

"A1"

data pattern. This is followed by either

an

1.0. address mark, or

an

"F8"

which is a data ad-

dress mark pattern. The

"A1"

pattern is made unique by violating the encode rules of MFM by omitting one clock bit. This makes

the address mark pattern unique to any other serial bit combination. Each

1.0. and data field are followed by a 16 bit cyclic redundancy check (CRC) character used for data

verification. Each

CRC polynomial is unique for a particular data pattern.

is

com-

Surrounding

8.1

GAP LENGTH CALCULATIONS

8.1.1

GAP 1

The

1.0. and data field are gaps called Interrecord gaps.

Gap 1 's purpose is to provide a head switching recovery period so that when switching from one track to another, sequential sectors may 11

bytes long which corresponds to the head switching time of 20 microseconds1 Gap 1

followed by a sync field for the

be

read without waiting the rotational latency time. Gap 1 should

1.0. field of the first sector.

be

at least

is

immediately

8.1.2 GAP 2

Following the 1.0. field, and separating the 1.0. field from the data field, area for the data field write update splice to occur.

The

for the data field address mark.

length of gap 2 is determined by the data separator lock up perfor-

The

remainder of this gap also serves as the sync up area

is

gap

2.

Gap 2 provides a known

mance.

8.1.3 GAP 3

Gap

3,

following the data field, is a speed variation tolerance area. This allows for a situation where a track has been formatted while the disk ing

3% faster than nominal (power line variations).

Gap 3 should

be

at least 15 bytes

is

running 3% slower than nominal, then write updated with the disk runn-

in

length.

8.1.4 GAP 4

Gap 4 is a speed tolerance buffer for the entire track. This allows the disk to rotate at least 3% faster than normal without overflowing the track during the format operation. The format operation which writes the

1.0.

fields, begins with the first encountered index and continues to the next index.

25

8.2 WRITE PRECOMPENSATION

Whenever two bits are written curs, which tends to cause the two bits to move away from each other. This

Other phenomenon such degree.

The

effect of bit shift can will occur early and which bits will occur late, can the expected shift.

Bit shift is more apparent should only be at track number greater than 128.

The

optimum amount of pre-compensation for the bits. TABLE

4 shows various bit patterns for pre-compensation.

in

close proximity to each other, a phenomenon called pulse superposition oc-

as

random noise, speed variation, etc., will also cause bit shift, but to a lesser

be

reduced by a technique called precompensation which, by detecting which bits

be

done by writing these bits

on

the innermost data tracks due to pulse crowding. Therefore, precompensation

SA

1000

is

12

nanoseconds for both early and late written

WRITE

POSITION

o 0

0 0

o 0 o 0 1

0

1

0

o 0 1 1 o 1

o 0

DIRECTION

On

Time Clock

Late Clock

=

On

Time Data

Early Data

OF

SHIFT

o 1 o 1 o 1 1 0 o 1

1 1

100

1 o 0 1

1 0 1 1

o 1

o 0

1 1

1 1 o 1

1

1 1

1

1 1 1

0 0

1

0

= Late Data =

On

Time Data

Early Clock

=

On

Time Clock

On

Time Data

Early Data

=

= Late Data =

On

Time Data

is

a large factor of bit shift.

in

the opposite direction of

Table

4.

Write Precompensation

Precompensation Pattern Detection bits are shifted through a 4 bit shift register. Bit third position.

INDEX~------------------------------~ll~-------------------------------------------

GAP

WRITE

UPDATE

-------------------------'

16

1 SYNC

x '4E'

ID.A.M.

----

NOTES:

1,

NOMINAL

2.

MINIMUM

3.

WRITE

4.

HEAD SWITCHING TIME = 20 MICROSECONDS.

TRACK CAPACITY - 10416 BYTES.

TRACK CAPACITY -

TO

READ RECOVERY TIME = 20 MICROSECONDS.

Figure

DATA

A.M.

----

(NOMINA~

21

Track Format

DATA

FIELD

256 x USER

-

3%

SPEED VARIANCE) 10102 BYTES.

DATA

is

written out of the

GAP

3

15

x '4E' 352 x '4E'

GAP

nL

4

26

9.0

SA1000 JUMPER OPTIONS

The

following jumper options are located

tions.

on

the control

PCB,

26050. Reference Figure 15 for the loca-

JUMPER

Fault When jumpered, this option disables the fault detection circuitry. Ready When jumpered, this option Drive

Select When jumpered, this option selects the designated drive.

(081 -

-5,

4)

-15

Volts When jumpered

FUNCTION

in

the be used when the input figuration, this option

,~~~~

••

~~

®

allows a -15 volt input to

FAULT

enables

~5

volt configuration, this option bypasses the regulator chip - to

voltage is rated at

an

active ready signal at the interface.

-5

volts

..

When jumpered in the -15 volt con-

be

regulated to

-5

READY

volts.

J

-5,

- 15

VOLTS

JUMPER

Figure 22 SA1000 Control PCB

27

10.0 SA1000 UNPACKAGING INSTRUCTIONS Attention: These instructions must

1.

The

spindle lock (PIN 60464) must

2.

the figure

To

prevent possible damage to the heads and media, rotate the spindle

below). Retain the lock for reinstallation prior to transporting the drive.

only.

3.

To

isolate the

AC

ground from logic ground, remove the motor ground strap (PIN 60060).

be

carefully followed to insure the proper operation of the drive.

be

removed before applying

AC

power

to

the drive (reference

in

a clockwise direction

Figure 23

SA

1000 Packaging

28

Shugart SA1000, SA1002, SA1004 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual