Fujitsu MAN3184 SERIES, MAN3367 SERIES, MAN3735 SERIES Specifications

C141-E123-01EN

MAN3184, MAN3367, MAN3735 SERIES

DISK DRIVES

SCSI PHYSICAL INTERFACE SPECIFICATIONS

This Product is designed, developed and manufactured as contemplated for general use, including
without limitation, general office use, personal use and household use, but is not designed,
developed and manufactured as contemplated for use accompanying fatal risks or dangers that,
unless extremely high safety is secured, could lead directly to death, personal injury, severe
physical damage or other loss (hereinafter “High Safety Required Use”), including without
limitation, nuclear power core control, airplane control, air traffic control, mass transport operation
control, life support, weapon launching control. You shall not use this Product without securing the
sufficient safety required for the High Safety Required Use. If you wish to use this Product for
High Safety Required Use, please consult with our sale person in charge before such use

The contents of this manual is subject to change without prior notice.

All Rights Reserved. Copyright  2001 FUJITSU LIMITED

C141-E123-01EN i

FOR SAFE OPERATION

Handling of This manual

This manual contai ns important i nformation fo r using this p roduct . Rea d thor oughly befor e using
the product. Use this product only after thoroughly reading and understanding especially the
section “Important Alert Items” in this manual. Keep this manual handy, and keep it carefully.

FUJITSU makes every effort to prevent users and bystanders from being injured or from suffering
damage to their property. Use the product according to this manual.

Functional Limitations

There may be certain functional limitations concerning the specifications and functions of the
products co vered by this manual depend ing on the equipment vers ion, especially co ncerning the
following functions.

Versions in which there functions can be used will be communicated through “ENGINEERING
CHANGE REQUEST/NOTICE”, issued by Fujitsu.

Function Equipment Version Which Supports These Functions

Equipment
Version No.

EPROM
Version No.

Standard INQUIRY Data Product
Revision (ASCII)

WRITE RAM Command

These commands cannot be used in the current version.

READ RAM Command

(Proceed to the Copyright Page)

C141-E123-01ENii

Related Standards

Specifications and functions of products covered by this manual comply with the following
standards.

Standard (Text) No. Name Enacting Organization

T10/1302D Rev 14
(final)

Working Draft
American National Standard Information
Technology --- SCSI Parallel Interface 3

American National
Standards Institute
(ANSI)

All Rights Reserved, Copyright  2001 Fujitsu Limited

C141-E123-01EN iii

REVISION RECORD

Edition Date

published

Revised contents

01 Mar.,2001

Specification No.: C141-E123-**EN

The contents of this manual is subject to
change without prior notice.

All Rights Reserved.
Copyright  2001
FUJITSU LIMITED

This page is intentionally left blank.

C141-E123-01EN v

PREFACE

This manual explains the MAN3184/MAN3367/MAN3735 series 3-1/2" intelligent disk drives each having
the built-in SCSI controller.

This manual details the specifications and functions of the Small Computer System Interface (SCSI) to
connect the above listed disk drives to the user system. Also, the manual details various SCSI command
specifications and the command processing functions, and provides the information required to creation of
host system software. This manual is int ended to be used b y the users who have the basic knowledge of
computer system operations.

The following lists the manual configuration and the contents of each chapter. The caution labels and
markings are also explained.

Manual Configuratio n and Contents

This manual consists of the following three chapters, and the terminologies and abbreviations sections.

Chapter 1 SCSI Bus

This chapter describes the configuration, physical and electrical requirements, interface protocol, and
other operations of the Small Computer System Interface (SCSI) which connects the
MAN3184/MAN3367/MAN3735 ser i es i nt e lligent disk drives to the user system.

Chapter 2 SCSI Messages

This chapter describes the type and explanation of messages defined for SCSI bus operations.

Chapter 3 ERROR Recovery

This chapter describes error recovery processing executed by the MAN3184/MAN3367/MAN3735 series
intelligent disk drives in response to various errors on the SCSI bus.

Glossary

This section explains the terminologies the reader must understand to read this manual.

Abbreviations

This section lists the abbreviated terms and their full words used in this manual.

C141-E123-01ENvi

CONVENTIONS

This manual uses the fo l lowing conventions:

NOTE:

NOTE indicates the information useful for the user to operate the system.

Important information

The important information is provided with the "Important" title. The important information text is
centered so t hat the reader can distinguish it from ot her manual texts. The following gives an example:

IMPORTANT

The IDD operates as a target (TARG) on the SCSI bus. The IDD is
called "TARG" in this chapter except when clear identification is
required.

Notations

A decimal value is indicated as it is in this manual.
A hexadecimal value is indicated in the X'17B9' or 17B9h or 17B9H notation.
A binary value is indicated in the notation similar to "010."

The disk drive model name has a different suffix depending on its SCSI electrical characteristics, capacity,
data format used during shipment and others. The following typical model name is used except when the
model needs to be distinguished. Also, the disk unit may be referred to as the "IDD" or "unit" in this
manual.

C141-E123-01EN vii

Note 1:

Model name

M AN 3

184 MC

Interface type MP: Low-Voltage Differential, 16-bit SCSI Ultra-160m,

68-pin connector
MC: Low-Voltage Differential, 16-bit SCSI Ultra-160m,
SCA-2 connector

Formatted capacity (100 MB units)

Disk size

Type AN: 1-inch height (10,025 rpm)

Note 2:

Typical model name

Type model name Model name
MAN3184 MAN3184MP, MAN3184MC
MAN3367 MAN3367MP, MAN3367MC
MAN3735 MAN3735MP, MAN3735MC

Requesting for User's Comments

Please use the User's Comment Form attached to the end of this manual to identify user comments including
error, inaccurate and misleading information of this manual. Contact to your Fujitsu representative for
additional comment forms if required.

C141-E123-01ENviii

MANUAL ORGANIZATION

Product/

Maintenance Manual

• General Description

• Specifications

• Data Format

• Installation Requirements

• Installation

• Diagnostics and Maintenance

• Error Analysis

• Principle of Operation

SCSI Physical

Interface

Specifications

• SCSI Bus

• SCSI Message

• Error Recovery

SCSI Logical

Interface

Specifications

• Command Processing

• Data Buffer Management

• Command Specifications

• Parameter Data Formats

• Sense Data and Error Recovery Methods

• Disk Media Management

C141-E123-01EN ix

CONTENTS

page

CHAPTER 1 SCSI BUS......................................................................................................................1 - 1

1.1 System Configuration .................................................................................................................. 1 - 1

1.2 Interface Signal Definition...........................................................................................................1 - 3

1.3 Physical Requirements ....................................................................................................... .......... 1 - 7

1.3.1 Interface connector......................................................................................................................1 - 8

1.3.2 Interface cable............................................................................................................................1 - 15

1.4 Electrical Requirements............................................................................................................. 1 - 17

1.4.1 Single-Ended type......................................................................................................................1 - 17

1.4.2 Low-Voltage Differential type................................................................................................... 1 - 20

1.4.3 Internal terminal resistor and power supply for terminating resistor ......................................... 1 - 23

1.4.4 Usage in 8-bit/16-bit transfer mode...........................................................................................1 - 25

1.4.5 Signal driving conditions................................................................................................. .......... 1 - 26

1.5 Timing Rule............................................................................................................................... 1 - 28

1.5.1 Timing value.............................................................................................................................. 1 - 28

1.5.2 Measurement point....................................................................................................................1 - 35

1.6 Bus Phases.................................................................................................................................1 - 39

1.6.1 BUS FREE phase.......................................................................................................................1 - 40

1.6.2 ARBITRATION phase.............................................................................................................. 1 - 41

1.6.3 SELECTION phase ...................................................................................................................1 - 44

1.6.4 RESELECTION phase..............................................................................................................1 - 48

1.6.5 INFORMATION TRANSFER phases.......................................................................................1 - 51

1.6.5.1 Asynchronous transfer mode .....................................................................................................1 - 52

1.6.5.2 Synchronous mode..................................................................................................................... 1 - 55

1.6.5.3 Wide mode transfer (16-bit SCSI) ........................................................................................ ..... 1 - 65

1.6.6 COMMAND phase.................................................................................................................... 1 - 65

1.6.7 DATA phase..............................................................................................................................1 - 65

1.6.8 STATUS phase..........................................................................................................................1 - 68

1.6.9 MESSAGE phase.......................................................................................................................1 - 68

1.6.10 Signal requirements concerning transition between bus phases.................................................1 - 69

1.6.11 Time monitoring feature ............................................................................................................1 - 71

1.7 Bus Conditions ..........................................................................................................................1 - 72

1.7.1 ATTENTION condition ............................................................................................................1 - 72

1.7.2 RESET condition.......................................................................................................................1 - 75

1.8 Bus Phase Sequence ..................................................................................................................1 - 76

x C141-E123-01EN

1.9 SCAM........................................................................................................................................ 1 - 84

1.9.1 SCAM operations......................................................................................................................1 - 84

1.10 Ultra SCSI .................................................................................................................................1 - 89

1.10.1 Outline....................................................................................................................................... 1 - 89

1.10.2 Device connection .....................................................................................................................1 - 89

1.10.3 Electrical characteristics of SCSI parallel interface...................................................................1 - 90

1.11 Low-Voltage Differential...........................................................................................................1 - 94

1.11.1 Ultra2-SCSI............................................................................................................................... 1 - 94

1.11.2 Ultra-160M................................................................................................................................1 - 94

1.11.3 LVD driver characteristics.........................................................................................................1 - 94

1.11.4 LVD receiver characteristics .....................................................................................................1 - 95

1.11.5 LVD capacitive loads ................................................................................................................ 1 - 96

1.11.6 System level requirements for LVD SCSI drivers and receivers...............................................1 - 97

1.12 SCSI bus fairness.......................................................................................................................1 - 98

CHAPTER 2 SCSI MESSAGE ..........................................................................................................2 - 1

2.1 Message System...........................................................................................................................2 - 1

2.1.1 Message format............................................................................................................................2 - 1

2.1.2 Message type...............................................................................................................................2 - 2

2.1.3 Message protocol......................................................................................................................... 2 - 4

2.2 SCSI Pointer................................................................................................................ ................ 2 - 5

2.3 Message Explanation...................................................................................................................2 - 8

2.3.1 TASK COMPLETE message: X'00'(T→I).................................................................................2 - 8

2.3.2 SAVE DATA POINTER message: X'02'(T→I).........................................................................2 - 8

2.3.3 RESTORE POINTERS message: X'03' (T→1)..........................................................................2 - 8

2.3.4 DISCONNECT message: X'04' (T→I)........................................................................................2 - 8

2.3.5 INITIATOR DETECTED ERROR message: X'05'(I→T).........................................................2 - 9

2.3.6 ABORT TASK SET message: X'06' (I→T)............................................................................... 2 - 9

2.3.7 MESSAGE REJECT message: X'07'(I↔T)............................................................................. 2 - 10

2.3.8 NO OPERATION message: X'08' (I→T).................................................................................2 - 10

2.3.9 MESSAGE PARITY ERROR message: X'09' (I→T)..............................................................2 - 10

2.3.10 LINKED TASK COMPLETE message: X'0A'(T→I) ..............................................................2 - 11

2.3.11 TARGET RESET message: X'0C' (I→T).................................................................................2 - 11

2.3.12 ABORT TASK message: X'0D' (I→T) ....................................................................................2 - 11

2.3.13 CLEAR TASK SET message: X'0E'(I→T)..............................................................................2 - 11

2.3.14 CONTINUE TASK message: X'12' (I→T) ..............................................................................2 - 12

C141-E123-01EN xi

2.3.15 TARGET TRANSFER DISABLE message : X'13' (I→T) .......................................................2 - 12

2.3.16 Task attribute messages.............................................................................................................2 - 13

2.3.17 IGNORE WIDE RESIDUE message: X'23' (T→I)..................................................................2 - 14

2.3.18 IDENTIFY message: X'80' to X'FF' (I↔T)..............................................................................2 - 15

2.3.19 SYNCHRONOUS DATA TRANSFER REQUEST message (I↔T) .......................................2 - 16

2.3.20 WIDE DATA TRANSFER REQUEST message (I↔T)........................................................... 2 - 24

2.3.21 PARALLEL PROTOCOL REQUEST message (I↔T) ............................................................2 - 28

CHAPTER 3 ERROR RECOVERY..................................................................................................3 - 1

3.1 Error Conditions and Retry Procedure.........................................................................................3 - 1

3.2 Recovery Control.........................................................................................................................3 - 6

GLOSSARY

....................................................................................................................................GL

-

1

ABBREVIATION

.................................................................................................................................AB

-

1

xii C141-E123-01EN

FIGURES

page

1.1 Example of SCSI configuration...................................................................................................1 - 2

1.2 Interface signals...........................................................................................................................1 - 3

1.3 DATA BUS and SCSI ID ............................................................................................................1 - 4

1.4 SCSI interface connector (IDD side) (16-bit SCSI).....................................................................1 - 8

1.5 SCSI interface connector (cable side) (16-bit SCSI)....................................................................1 - 9

1.6 Single-ended connector pin assignment (16-bit SCSI)...............................................................1 - 10

1.7 Low-Voltage-Differential connector pin assignment (16-bit SCSI)...........................................1 - 11

1.8 SCA-2 type, 16-bit SCSI interface connector (IDD side) ..........................................................1 - 12

1.9 SCA-2 Type, single-ended 16-bit SCSI connector signal assignment........................................1 - 13

1.10 SCA Type, Low-Voltage-Differential connector signal assignment..........................................1 - 14

1.11 Connection of interface cable..................................................................................................... 1 - 16

1.12 Single-Ended SCSI termination circuit-1...................................................................................1 - 17

1.13 Single-Ended SCSI termination circuit-2...................................................................................1 - 18

1.14 LVD SCSI termination circuit....................................................................................................1 - 20

1.15 Circuit for mated indications......................................................................................................1 - 23

1.16 16-bit SCSI (not SCA2) terminating resistor circuit..................................................................1 - 24

1.17 Fast-5/10 Measurement Point ....................................................................................................1 - 35

1.18 Fast-20 Measurement Point........................................................................................................ 1 - 36

1.19 LVD ST Data Transfer measurement point ...............................................................................1 - 37

1.20 LVD DT Data Transfer measurement point...............................................................................1 - 38

1.21 BUS FREE phase.......................................................................................................................1 - 40

1.22 ARBITRATION phase ..............................................................................................................1 - 43

1.23 SELECTION phase....................................................................................................................1 - 47

1.24 RESELECTION phase...............................................................................................................1 - 50

1.25 INFORMATION TRANSFER phase (phase control) ...............................................................1 - 51

1.26 Transfer in asynchronous mode .................................................................................................1 - 54

1.27 ST transfer in synchronous mode...............................................................................................1 - 58

1.28 Data Group Pad field and pCRC field transfer ..........................................................................1 - 64

1.29 Data sequence at data transfer....................................................................................................1 - 65

1.30 Data transfer rate in synchronous mode.....................................................................................1 - 68

1.31 Switching direction of transfer over data bus.............................................................................1 - 70

1.32 ATTENTION condition.............................................................................................................1 - 74

1.33 RESET condition.......................................................................................................................1 - 76

C141-E123-01EN xiii

1.34 Bus phase sequence....................................................................................................................1 - 77

1.35 Example of bus phase transition at execution of a single command ..........................................1 - 79

1.36 State of level-1 SCAM target.....................................................................................................1 - 86

1.37 State of level-2 SCAM target............................................................................................... ......1 - 87

1.38 Comparison of active negate current and voltage ......................................................................1 - 92

1.39 Single-ended test circuit.............................................................................................................1 - 93

1.40 LVD transceiver architecture.....................................................................................................1 - 95

1.41 Connection to the LVD receivers...............................................................................................1 - 95

1.42 Differential SCSI bus capacitive loading...................................................................................1 - 96

2.1 Message format............................................................................................................................2 - 2

2.2 SCSI pointer configuration..........................................................................................................2 - 7

xiv C141-E123-01EN

TABLES

page

1.1 INFORMATION TRANSFER phase identification....................................................................1 - 6

1.2 Single-Ended maximum distance between terminators................................................................1 - 7

1.3 LVD maximum distance between terminators.............................................................................1 - 8

1.4 SE and LVD Transmission line impedance of cable at maximum indicated

data transfer rate.........................................................................................................................1 - 15

1.5 Attenuation Requiaments for SCSI cable media........................................................................1 - 15

1.6 Output characteristic..................................................................................................................1 - 19

1.7 Input characteristic.....................................................................................................................1 - 19

1.8 LVD DIFFSENS driver specifications.......................................................................................1 - 21

1.9 DIFFSENS receiver operating requirements..............................................................................1 - 21

1.10 Requirements for terminating resistor power supply..................................................................1 - 23

1.11 Setting set up pin, 16-bit (wide)/8-bit (narrow) mode................................................................1 - 25

1.12 Signal status at receiving end.....................................................................................................1 - 26

1.13 Signal driving method ................................................................................................................1 - 26

1.14 Bus phases and signal sources....................................................................................................1 - 27

1.15 SCSI bus control timing values..................................................................................................1 - 28

1.16 SCSI bus data & information phase ST timing values...............................................................1 - 28

1.17 SCSI bus data & information phase DT timing values...............................................................1 - 29

1.18 Parameters used for fast synchronous data transfer mode..........................................................1 - 67

1.19 Retry count setting for RESELECTION phase..........................................................................1 - 71

1.20 Maximum capacitance ...............................................................................................................1 - 97

1.21 System level requirements.........................................................................................................1 - 98

2.1 SCSI message...............................................................................................................................2 - 3

2.2 Extended message........................................................................................................................2 - 4

2.3 Definition of data transfer mode by message exchange.............................................................2 - 17

2.4 Synchronous mode data transfer request setting ........................................................................2 - 19

2.5 Transfer mode setup request from INIT to IDD ........................................................................2 - 21

2.6 Transfer mode setup request from IDD to INIT ........................................................................2 - 23

2.7 Data bus width defined by message exchange...........................................................................2 - 25

2.8 Wide mode setting request from the INIT to the IDD................................................................2 - 27

2.9 Wide mode setting request from the IDD to the INIT................................................................2 - 28

2.10 TRANSFER PERIOD FACTOR field.......................................................................................2 - 29

2.11 Valid protocol options bit combinations....................................................................................2 - 30

C141-E123-01EN xv

2.12 PARALLEL PROTOCOL REQUEST message implied agreement..........................................2 - 32

3.1 Retry procedure for SCSI error ....................................................................................................3 - 7

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C141-E123-01EN 1 - 1

CHAPTER 1 SCSI BUS

1.1 System Configuration

1.2 Interface Signal Definition

1.3 Physical Requirements

1.4 Electrical Requirements

1.5 Timing Rule

1.6 Bus Phases

1.7 Bus Conditions

1.8 Bus Phase Sequence

1.9 SCAM

1.10 Ultra SCSI

1.11 Low-Voltage Differential

1.12 SCSI Bus Fairness

This chapter describes the configuration, physical and electrical characteristics, interface protocol, and
operations of SCSI buses.

Note:

The IDD operates as a target (TARG) on the SCSI bus. The IDD is called "TARG" in this
chapter except when clear identification is required.

1.1 System Configuration

Up to 16-bit SCSI series models can be connected to the system via the SCSI bus. Figure 1.1 gives
an example of multi-host system configuration.

Each SCSI device operates as an initiator (INIT) or a target (TARG). Only a single INIT and a
single TARG selected by this INIT can operate simultaneously on the SCSI bus.

The system configuration allows any combination of a SCSI device to operate as the INIT and a
SCSI device to o pe ra te as t he T ARG. Also , a ny devic e ha ving b ot h the I NI T a nd TARG functions
can be used on the SCSI bus.

Each SCSI device is assigned a unique address (or SCSI ID). The SCSI ID corresponds to a bit
number of the SCSI data bus. While the INIT uses a logical unit number (LUN) to select an I/O
unit to be connected under TARG control.

C141-E123-01EN1-2

Any SCSI ID of the IDD can be selected using the setup pins. However, the LUN is fixed to zero
(0). The SCSI ID can be 0 to 15.

Note:

The maximum number of SCSI devices and the maximum cable length are limited depending
on the selected SCSI data transfer mode and the SCSI transceiver type. Appropriate SCSI
devices and cable length must be determined for each system.

Figure 1.1 Example of SCSI configuration

C141-E123-01EN 1 - 3

1.2 Interface Signal Definition

Figure 1.2 shows interface signal types. The SCSI bus consists of 27 signal lines. The 27 signal
lines consist of data buses (2 bytes plus two odd parity bits) and 9 control signal lines.

The SCSI bus can be a single-ended or low voltage differential(LVD) interface depending on the
model used. Their physical and electrical characteristics are detailed in Sections 1.3 and 1.4.

P_CRCA (18)

Figure 1.2 Interface signals

C141-E123-01EN1-4

(1) DB15 to DB00, P1, P_CRCA (Data buses)

The 16-bit SCSI system uses a bidirectional data bus consisting of two-byte data and two odd
parity bits.

MSB (2

15

): DB15, LSB (20): DB00

The data bus is used to transfer a command, data, a status, or a message in the INFORMATION
TRANSFER phase. However, DB15 to DB08 and P1 are used for data transfer only. The data is
transferred only after the WIDE DATA TRANSFER REQUEST or PARALLEL PROTOCOL
REQUEST message has been exchanged and the 16-bit data transfer mode has been established
between the INIT and TARG.

In the ARBITRATION phase, the data bus is used to send a SCSI ID to determine the bus
arbitration priority. In the SELECTION or RESELECTION phase, the data bus is used to send a
SCSI ID of the INIT and TARG. Figure 1.3 shows the relationship between the data buses and
SCSI IDs.

DB15 DB14 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0

SCSI ID #15

SCSI ID #14

SCSI ID #9

SCSI ID #8

SCSI ID #7

SCSI ID #6

SCSI ID #5

SCSI ID #4

SCSI ID #3

SCSI ID #2

SCSI ID #1

SCSI ID #0

Data bus

(16 bit SCSI)

Figure 1.3 DATA BUS and SCSI ID

(a) DB15 to 0

Sixteen data-bit signals that form the 16-bit DATA BUS.

(b) DB7 to 0

Eight data-bit signals that form the 16-bit DATA BUS.

(c) P1 (ST DATA phase)

A signal sourced by the SCSI device driving the data bus during ST DATA phases. This signal is
associated with the DB(15-8) signals and is used to detect the presence of an odd number of bit
errors within the byte. The parity bit is driven such that the number of logical ones in the byte plus
the parity bit is odd.

C141-E123-01EN 1 - 5

(d) P1 (data group transfer enabled)

A signal that shall be continuously negated by the SCSI device driving the DB(15-0) signals and
shall be ignored by the SCSI device receiving the DB(15-0) signals during DT DATA phases.

(e) P_CRCA (PARITY/CRC AVAILABLE) (SELECTION p hase, ST DATA phase, COMMAND phase,

MESSAGE phase, or STATUS phase)

A signal sourced by the SCSI device driving the data bus during these phases. This signal is
associated with the DB(7-0) signals and is used to detect the presence of an odd number of bit
errors within the byte. The parity bit is driven such that the number of logical ones in the byte plus
the parity bit is odd.

The parity bits (P1 and P_CRCA) is op tional for the system. The I DD handles the data bus parity
as follows:

• The IDD has the data bus parity check function, and can enable or disable the parity check.

See Section 5.3.2 "SCSI Parity" of the Product Manual for setup details.

• When valid data is sent to the data bus from the IDD, the parity data is always guaranteed

except for the ARBITRATION phase.

(f) P_CRCA (data group transfer enabled)

A signal sourced by a target during DT DATA phases to control whether a data group field is a pad
field, pCRC field, or data field. When asserted the data group field shall b e pad or pCRC fields
that shall not be transferred to the ULP. When negated the data group field shall be a data field that
shall be transferred to the ULP.

Note:

ULP is "Upper Level Protocol".

C141-E123-01EN1-6

(2) BSY (BUSY)

The BSY signal indicates that the SCSI bus is in use. In the ARBITRATION phase, this signal is
used to request for the bus usage priority.

(3) SEL (SELECT)

The SEL signal is used by the INIT to select a TARG (in the SELECTION phase) or by the TARG
to reselect an INIT (in the RESELECTION phase).

(4) C/D (CONTROL/DATA)

This is a combination of I/O and MSG signals, and specifies a type of information transferred on
the data bus. The C/D signal is always driven by the TARG (see Table 1.1).

(5) I/O (INPUT/OUTPUT)

The I/O signal specifies the information transmission direction on the data bus. It is also used to
identify the SELECTION phase or RESELECTION phase. This signal is always driven by the
TARG (see Table 1.1).

(6) MSG (MESSAGE)

A signal sourced by a target to indicate the MESSAGE phase or a DT DATA phase depending on
whether C/D is true or false. Asserted indicates MESSAGE or DT DATA (see Table 1.1).

Table 1.1 INFORMATION TRANSFER phase identification

Signal

C/D MSG I/O

Phase Direction Comment

0 0 0 ST DATA OUT INIT -> TARG
0 0 1 ST DATA IN INIT <- TARG

ST Data phase

0 1 0 DT DATA OUT INIT -> TARG
0 1 1 DT DATA IN INIT <- TARG

DT Data phase

Data phase

1 0 0 COMMAND INIT -> TARG
1 0 1 STATUS INIT <- TARG
1 1 0 MESSAGE OUT INIT -> TARG
1 1 1 MESSAGE IN INIT <- TARG

MESSAGE

C141-E123-01EN 1 - 7

(7) REQ (REQUEST)

This is a transmission request from the TARG to the INIT in the INFORMATION TRANSFER
phase.

(8) ACK (ACKNOWLEDGE)

The ACK signal is a response to the REQ signal sent from the INIT to TARG in the
INFORMATION TRANSFER phase.

(9) ATN (ATTENTION)

The ATN signal indicates that the INIT has a message to be sent to the TARG. It is used to
generate an ATTENTION condition.

(10) RST (RESET)

The RST signal is a Reset signal to clear all SCSI devices on the bus (to the RESET condition).

1.3 Physical Requirements

All SCSI devices are connected to each other in a daisy chain. Both ends of the interface cable are
terminated with resistor.

Tables 1.2 and 1.3 define the SCSI bus electrical characteristics (for interface signal
driver/receiver).

Table1.2 Single-Ended maximum distance between terminators

Maximum distance between

terminators (meters)

FAST-5 FAST-10 FAST-20
2 to 4 devices 6 3 3
5 to 8 devices 6 3 1.5

9 to 16 devices 6 3 N/A

Number of

attached devices

C141-E123-01EN1-8

Table1.3 LVD maximum distance between terminators

Maximum distance between terminators (meters)

Interconnect

Fast-5 Fast-10 Fast-20 Fast-40 Fast-80

Point-to-point 25 25 25 25 25

Multidrop 12 12 12 12 12

1.3.1 Interface connector

(1) Interface connector of the 16-bit SCSI

The IDD 16-bit SCSI bus connector is nonshielded 68-pin, consisting of two 34-pin rows with
adjacent pins 1.27 mm (0.05 inch) part (Figure 1.4).

For the interface cable connector, use a nonshielded 68-contact socket consisting of two 34-contact
rows points with adjacent contact points 1.27 mm (0.05 inch) apart (Figure 1.5).

Figure 1.6 shows single-ended interface connector signal assignment.

Figure 1.7 shows low-voltage-differential interface connector signal assignment.

Figure 1.4 SCSI interface connector (IDD side) (16-bit SCSI)

C141-E123-01EN 1 - 9

M

M

0.61

5.16

0.001

0.396

Figure 1.5 SCSI interface connector (cable side) (16-bit SCSI)

C141-E123-01EN1-10

Pin No. Signal Signal Pin No.

01 GND -DB12 35
02 GND -DB13 36
03 GND -DB14 37
04 GND -DB15 38
05 GND -DBP1 39
06 GND -DB00 40
07 GND -DB01 41
08 GND -DB02 42
09 GND -DB03 43
10 GND -DB04 44
11 GND -DB05 45
12 GND -DB06 46
13 GND -DBP7 47
14 GND -P_CRCA 48
15 GND GND 49
16 GND GND 50
17 TERMPWR * TERMPWR * 51
18 TERMPWR * TERMPWR * 52
19 (reserved) (reserved) 53
20 GND GND 54
21 GND -ATN 55
22 GND GND 56
23 GND -BSY 57
24 GND -ACK 58
25 GND -RST 59
26 GND -MSG 60
27 GND -SEL 61
28 GND -C/D 62
29 GND -REQ 63
30 GND -I/O 64
31 GND -DB08 65
32 GND -DB09 66
33 GND -DB10 67
34 GND -DB11 68

* Terminating resistor power

Figure 1.6 Single-ended connector pin assignment (16-bit SCSI)

C141-E123-01EN 1 - 11

Pin No. Signal Signal Pi n No.

01 +DB(12) -DB(12) 35
02 +DB(13) -DB(13) 36
03 +DB(14) -DB(14) 37
04 +DB(15) -DB(15) 38
05 +DB(P1) -DB(P1) 39
06 +DB(0) -DB(0) 40
07 +DB(1) -DB(1) 41
08 +DB(2) -DB(2) 42
09 +DB(3) -DB(3) 43
10 +DB(4) -DB(4) 44
11 +DB(5) -DB(5) 45
12 +DB(6) -DB(6) 46
13 +DB(7) -DB(7) 47
14 +P_CRCA -P_CRCA 48
15 GROUND GROUND 49
16 DIFFSENS GROUND 50
17 TERMPWR * TERMPWR * 51
18 TERMPWR * TERMPWR * 52
19 RESERVED RESERVED 53
20 GROUND GROUND 54
21 +ATN -ATN 55
22 GROUND GROUND 56
23 +BSY -BSY 57
24 +ACK -ACK 58
25 +RST -RST 59
26 +MSG -MSG 60
27 +SEL -SEL 61
28 +C/D -C/D 62
29 +REQ -REQ 63
30 +I/O -I/O 64
31 +DB(8) -DB(8) 65
32 +DB(9) -DB(9) 66
33 +DB(10) -DB(10) 67
34 +DB(11) -DB(11) 68

* Terminating resistor power

Figure 1.7 Low-Voltage-Differential connector pin assignment (16-bit SCSI)

C141-E123-01EN1-12

(2) Interface connector of SCA-2 type 16-bit SCSI

The 16-bit, SCA-2 type SCSI bus connectors of the IDD are 80-pin, unshielded connectors, each
having two rows of 40 parallel pins (separated 1.27 mm or 0.05" from each other) (see Figure 1.8).

Figure 1.9 shows the pin assignment of 16-bit, SCA-2 type single-ended SCSI interface connector.

Figure 1.8 SCA-2 type, 16-bit SCSI interface connector (IDD side)