Maxtor DIAMONDMAX VL20 User Manual

®
Dia m o n d Ma x VL 2 0  
92041U4,91531U3and91021U2  
Part #1427/ A  
All material contained herein Copyright © 1999 Maxtor Corporation.  
MaxFax™ is a trademark of Maxtor Corporation. DiamondMax®,  
Maxtor® and No Quibble® Service are registered trademarks of Maxtor  
Corporation. Other brands or products are trademarks or registered  
trademarks of their respective holders. Contents and specifications  
subject to change without notice. All rights reserved.  
Corporate Headquarters  
510 Cottonwood Drive  
Milpitas, California 95035  
Tel: 408-432-1700  
Fax: 408-432-4510  
Research and Developm ent  
Engineering Center  
2190 Miller Drive  
Longmont, Colorado 80501  
Tel: 303-651-6000  
Fax: 303-678-2165  
Co n t e n t s  
S e c t io n 1 In t ro d u c t io n  
Maxtor Corporation  
Products  
1 - 1  
1 - 1  
1 - 1  
1 - 1  
1 - 1  
1 - 2  
1 - 2  
1 - 2  
1 - 2  
Support  
Manual Organization  
Abbreviations  
Conventions  
Key Words  
Numbering  
Signal Conventions  
S e c t io n 2 P ro d u c t De s c rip t io n  
The DiamondMax® VL 20  
Product Features  
2 - 2  
2 - 2  
2 - 2  
2 - 2  
2 - 2  
2 - 2  
2 - 2  
2 - 3  
2 - 3  
2 - 3  
2 - 3  
2 - 3  
2 - 4  
2 - 4  
2 - 4  
2 - 4  
2 - 4  
2 - 5  
2 - 5  
2 - 5  
2 - 5  
2 - 5  
2 - 5  
2 - 5  
2 - 6  
2 - 6  
2 - 6  
2 - 6  
2 - 6  
Functional/ Interface  
Zone Density Recording  
Read/ Write Multiple Mode  
UltraDMA - Mode 4  
Multi-word DMA (EISA Type B) - Mode 2  
Sector Address Translation  
Logical Block Addressing  
Defect Management Zone  
On-the-Fly Hardware Error Correction Code (ECC)  
Software ECC Correction  
Automatic Head Park and Lock Operation  
Cache Management  
Buffer Segmentation  
Read-Ahead Mode  
Automatic Write Reallocation (AWR)  
Write Cache Stacking  
Major HDA Components  
Drive Mechanism  
Rotary Actuator  
Read/ Write Electronics  
Read/ Write Heads and Media  
Air Filtration System  
Microprocessor  
Subsystem Configuration  
Dual Drive Support  
Cable Select Option  
Jumper Location/ Configuration  
Cylinder Limitation  
i
DIAMONDMAX VL 20 PR ODUCT MANUAL  
S e c t io n 3 P ro d u c t S p e c ific a t io n s  
Models and Capacities  
Drive Configuration  
Performance Specifications  
Physical Dimensions  
Power Requirements  
Power Mode Definitions  
Spin-up  
3 - 1  
3 - 1  
3 - 1  
3 - 2  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 3  
3 - 4  
3 - 4  
3 - 4  
3 - 4  
3 - 4  
3 - 4  
3 - 4  
3 - 5  
3 - 5  
3 - 5  
3 - 5  
Seek  
R ead/ Write  
Idle  
Standby  
Sleep  
EPA Energy Star Compliance  
Environmental Limits  
Shock and Vibration  
Reliability Specifications  
Annual Return Rate  
Quality Acceptance Rate  
Start/ Stop Cycles  
Data Reliability  
Component Design Life  
EMC/ EMI  
EMC Compliance  
Canadian Emissions Statement  
Safety Regulatory Compliance  
S e c t io n 4 Ha n d lin g a n d In s t a lla t io n  
Pre-formatted Drive  
4 - 1  
4 - 1  
4 - 1  
4 - 1  
4 - 2  
4 - 3  
4 - 3  
4 - 4  
4 - 4  
4 - 4  
4 - 4  
4 - 4  
4 - 4  
4 - 4  
4 - 5  
4 - 5  
4 - 5  
Important Notice  
Hard Drive Handling Precautions  
Electro-Static Discharge (ESD)  
Unpacking and Inspection  
R epacking  
Physical Installation  
Before You Begin  
Please Read  
Handling Precautions  
Tools for Installation  
Drive Identification Information  
Capacity Barriers  
Protecting Your Existing Data  
General Requirements  
System Hardware Requirements  
BIOS Requirements  
ii  
DIAMONDMAX VL 20 PR ODUCT MANUAL  
Ultra Direct Memory Access (UDMA)  
OS Requirements for Large Capacity Hard Drives  
Hard Drive Identification  
4 - 5  
4 - 5  
4 - 6  
4 - 6  
4 - 6  
4 - 6  
4 - 6  
4 - 7  
4 - 7  
4 - 7  
4 - 8  
4 - 8  
4 - 8  
4 - 10  
4 - 12  
Identifying IDE Devices on the Interface  
Jumper Settings  
Systems Using Cable Select  
Relationship to Other IDE Devices  
Mounting Drive in System  
Attaching Interface and Power Cables  
Attaching System Cables  
System Setup  
Setting the BIOS (CMOS)  
BIOS (CMOS) Parameters  
Hard Drive Preparation  
System Hangs During Boot  
S e c t io n 5 AT In t e rfa c e De s c rip t io n  
Interface Connector  
Pin Description Summary  
Pin Description Table  
PIO Timing  
5 - 1  
5 - 1  
5 - 2  
5 - 3  
5 - 4  
5 - 5  
DMA Timing  
Ultra DMA Timing Parameters  
S e c t io n 6 Ho s t S o ft w a re In t e rfa c e  
Task File Registers  
6 - 1  
6 - 1  
6 - 1  
6 - 1  
6 - 2  
6 - 2  
6 - 2  
6 - 2  
6 - 2  
6 - 3  
6 - 3  
6 - 3  
6 - 3  
6 - 3  
6 - 3  
6 - 3  
6 - 3  
6 - 4  
6 - 5  
6 - 5  
Data Register  
Error Register  
Features Register  
Sector Count Register  
Sector Number Register  
Cylinder Number Registers  
Device/ Head Register  
Status Register  
Command Register  
Read Commands  
Write Commands  
Mode Set/ Check Commands  
Power Mode Commands  
Initialization Commands  
Seek, Format, and Diagnostic Commands  
S.M.A.R.T. Commands  
Summary  
Control Diagnostic Registers  
Alternate Status Register  
iii  
DIAMONDMAX VL 20 PR ODUCT MANUAL  
Device Control Register  
Digital Input Register  
6 - 5  
6 - 5  
6 - 6  
Reset and Interrupt Handling  
S e c t io n 7 In t e rfa c e Co m m a n d s  
Command Summary  
Read Commands  
Read Sector(s)  
7 - 1  
7 - 2  
7 - 2  
7 - 2  
7 - 2  
7 - 3  
7 - 3  
7 - 3  
7 - 4  
7 - 4  
7 - 4  
7 - 4  
7 - 5  
7 - 5  
7 - 5  
7 - 5  
7 - 5  
7 - 7  
7 - 7  
7 - 7  
7 - 7  
7 - 7  
7 - 7  
7 - 7  
7 - 7  
7 - 9  
7 - 9  
7 - 12  
7 - 13  
7 - 14  
Read Verify Sector(s)  
Read Sector Buffer  
Read DMA  
Read Multiple  
Set Multiple  
Write Commands  
Write Sector(s)  
Write Verify Sector(s)  
Write Sector Buffer  
Write DMA  
Write Multiple  
Ultra DMA  
Set Feature Commands  
Set Features Mode  
Power Mode Commands  
Standby Immediate  
Idle Immediate  
Standby  
Idle  
Check Power Mode  
Set Sleep Mode  
Default Power-on Condition  
Initialization Commands  
Identify Drive  
Initialize Drive Parameters  
Seek, Format, and Diagnostic Commands  
S.M.A.R.T. Command Set  
S e c t io n 8 S e rvic e a n d S u p p o rt  
Service Policy  
No Quibble Service  
Support  
8 - 1  
8 - 1  
8 - 1  
Glo s s a ry  
Glossary  
GL - 1  
iv  
DIAMONDMAX VL 20 PR ODUCT MANUAL  
Fig u re s  
Fig u r e  
Tit le  
P a g e  
2 - 1  
3 - 1  
4 - 1  
4 - 2  
4 - 3  
4 - 4  
4 - 5  
4 - 6  
4 - 7  
5 - 1  
5 - 2  
5 - 3  
5 - 4  
5 - 5  
5 - 6  
5 - 7  
5 - 8  
5 - 9  
5 - 10  
5 - 11  
5 - 12  
5 - 13  
PCBA Jumper Location and Configuration  
Outline and Mounting Dimensions  
2 - 6  
3 - 2  
4 - 2  
4 - 3  
4 - 3  
4 - 5  
4 - 6  
4 - 7  
4 - 10  
5 - 1  
5 - 3  
5 - 4  
5 - 5  
5 - 6  
5 - 6  
5 - 7  
5 - 7  
5 - 8  
5 - 8  
5 - 9  
5 - 9  
5 - 10  
Multi-pack Shipping Container  
Single-pack Shipping Container (Option A)  
Single-pack Shipping Container (Option B)  
Master, Slave and Cable Select Settings  
5.25-inch Mounting Brackets and Rails  
IDE Interface and Power Cabling Detail  
Master, Slave and Cable Select Settings  
Data Connector  
PIO Data Transfer to/ from Device  
Multi-word DMA Data Transfer  
Initiating an Ultra DMA Data In Burst  
Sustained Ultra DMA Data In Burst  
Host Pausing an Ultra DMA Data In Burst  
Device Terminating an Ultra DMA Data In Burst  
Host Terminating an Ultra DMA Data In Burst  
Initiating an Ultra DMA Data Out Burst  
Sustained Ultra DMA Data Out Burst  
Device Pausing an Ultra DMA Data Out Burst  
Host Terminating an Ultra DMA Data Out Burst  
Device Terminating an Ultra DMA Data Out Burst  
v
SECTION 1  
In t ro d u c t io n  
Ma xt o r Co rp o ra t io n  
Maxtor Corporation has been providing high-quality computer storage products since 1982. Along the way,  
we’ve seen many changes in data storage needs. Not long ago, only a handful of specific users needed more than  
a couple hundred megabytes of storage. Today, downloading from the Internet and CD-ROMs, multimedia,  
networking and advanced office applications are driving storage needs even higher. Even home PC applications  
need capacities measured in gigabytes, not megabytes.  
P r o d u c t s  
Maxtor’s products meet those demanding storage capacity requirements with room to spare. They feature  
proven compatibility and reliability. While DiamondMax® VL 20 is the latest addition to our family of high  
performance 5,400 RPM desktop hard drives, DiamondMax® 40 series hard drives deliver industry-leading  
capacity and performance for demanding desktop and workstation applications.  
S u p p o r t  
No matter which capacity, all Maxtor hard drives are supported by our commitment to total customer  
satisfaction and our No Quibble® Service guarantee. One call – or a visit to our home page on the Internet  
(http:/ / www.maxtor.com) – puts you in touch with either technical support or customer service. We’ll  
provide you the information you need quickly, accurately and in the form you prefer – a fax, a downloaded  
file or a conversation with a representative.  
Ma n u a l Org a n iza t io n  
This hard disk drive reference manual is organized in the following method:  
Section 1 – Introduction  
Section 2 – Description  
Section 3 – Specifications  
Section 4 – Installation  
Section 5 – AT Interface  
Section 6 – Host Software Interface  
Section 7 – Interface Commands  
Section 8 – Service and Support  
Appendix – Glossary  
Ab b re via t io n s  
ABBRV DESCRIPTION  
ABBRV DESCRIPTION  
ATA AT attachment  
bpi bits per inch  
MB megabyte  
Mbits/sec megabits per second  
CHS cylinder - head - sector  
db decibels  
MB/sec megabytes per second  
MHz megahertz  
dBA decibels, A weighted  
DMA direct memory access  
ECC error correction code  
fci flux changes per inch  
ms millisecond  
MSB most significant bit  
mV millivolts  
ns nanoseconds  
G
acceleration  
PIO programmed input/output  
RPM revolutions per minute  
tpi tracks per inch  
GB gigabyte  
Hz hertz  
KB kilobyte  
UDMA ultra direct memory access  
µsec microsecond  
LBA logical block address(ing)  
LSB least significant bit  
mA milliamperes  
V
volts  
W
watts  
1 – 1  
DIAMO N DMAX VL 20 – IN TR O DUCTIO N  
Co n ve n t io n s  
If there is a conflict between text and tables, the table shall be accepted as being correct.  
Ke y Wo rd s  
The names of abbreviations, commands, fields and acronyms used as signal names are in all uppercase type  
(e.g., IDENTIFY DRIVE). Fields containing only one bit are usually referred to as the “name” bit instead of  
the “name” field.  
Names of drive registers begin with a capital letter (e.g., Cylinder High register).  
N u m b e r in g  
Numbers that are not followed by a lowercase “b” or “h” are decimal values. Numbers that are followed by  
a lowercase “b” (e.g., 01b) are binary values. Numbers that are followed by a lowercase “h” (e.g., 3Ah) are  
hexadecimal values.  
S ig n a l Co n ve n t io n s  
Signal names are shown in all uppercase type.  
All signals are either high active or low active signals. A dash character (-) at the end of a signal name  
indicates that the signal is low active. A low active signal is true when it is below ViL and is false when it is  
above ViH. A signal without a dash at the end indicates that the signal is high active. A high active signal is  
true when it is above ViH and is false when it is below ViL.  
When a signal is asserted, it means the signal is driven by an active circuit to its true state.  
When a signal is negated, it means the signal is driven by an active circuit to its false state.  
When a signal is released, it means the signal is not actively driven to any state. Some signals have bias  
circuitry that pull the signal to either a true or false state when no signal driver is actively asserting or negating  
the signal. These instances are noted under the description of the signal.  
1 – 2  
SECTION 2  
P ro d u c t De s c rip t io n  
Maxtor DiamondMax® VL 20 AT disk drives are 1-inch high, 3.5-inch diameter random access storage devices  
which incorporate an on-board ATA-5/ Ultra DMA 66 controller. High capacity is achieved by a balanced  
combination of high areal recording density and the latest data encoding and servo techniques.  
Maxtor's latest advancements in electronic packaging and integration methods have lowered the drive's power  
consumption and increased its reliability. Advanced giant magneto-resistive read/ write heads and a state-of-the-art  
head/ disk assembly - using an integrated motor/ spindle design - allow up to four disks in a 3.5-inch package.  
The new DiamondMax VL 20 (Value Line) series from Maxtor are 1- and 2-disk products expressly designed for  
entry-level commercial systems and consumer electronics applications where disk storage value is paramount.  
Available in capacities up to 20 GB, the VL series provides the proven quality and reliability of the original  
DiamondMax products and includes an UltraDMA 66 interface, 512 KB buffer and 9.5 ms seek performance.  
Dia m o n d Ma x VL 2 0 Ke y Fe a t u re s  
ANSI ATA-5 compliant PIO Mode 4 interface (Enhanced IDE)  
Supports Ultra DMA Mode 4 for up to 66.7 MB/ sec data transfers  
512 KB buffer with multi-adaptive cache manager  
5,400 RPM spin speed  
9.5 ms seek time  
Zone density and I.D.-less recording  
Outstanding shock resistance at 250 Gs  
High durability with 50K contact start/ stop cycles  
Advanced multi-burst on-the-fly Error Correction Code (ECC)  
Extended data integrity with ECC protected data and fault tolerant servo synchronization fields  
Supports EPA Energy Star Standards (Green PC Friendly) with ATA powering savings commands  
Auto park and lock actuator mechanism  
Low power consumption  
S.M.A.R.T. Capability  
Note: Maxtor defines one megabyte as 106 or one million bytes and one gigabyte as 109 or one billion bytes.  
2 – 1  
PRODUCTDESCRIPTION  
P ro d u c t Fe a t u re s  
Fu n c t io n a l / In t e rfa c e  
Maxtor DiamondMax VL 20 hard drives contain all necessary mechanical and electronic parts to interpret control  
signals and commands from an AT-compatible host computer. See Section 3 Product Specifications, for complete  
drive specifications.  
Zo n e De n s it y Re c o rd in g  
The disk capacity is increased with bit density management – common with Zone Density Recording. Each  
disk surface is divided into 16 circumferential zones. All tracks within a given zone contain a constant  
number of data sectors. The number of data sectors per track varies in different zones; the outermost zone  
contains the largest number of data sectors and the innermost contains the fewest.  
Re a d /Writ e Mu lt ip le Mo d e  
This mode is implemented per ANSI ATA/ ATAPI-5 specification. Read/ Write Multiple allows the host to  
transfer a set number of sectors without an interrupt request between them, reducing transfer process  
overhead and improving host performance.  
Ult ra DMA - Mo d e 4  
Maxtor DiamondMax VL 20 hard drives fully comply with the new ANSI Ultra DMA protocol, which  
greatly improves overall AT interface performance by significantly improving burst and sustained data  
throughput.  
Mu lt i-w o rd DMA (EIS A Typ e B) - Mo d e 2  
Supports multi-word Direct Memory Access (DMA) EISA Type B mode transfers.  
S e c t o r Ad d re s s Tra n s la t io n  
All DiamondMax VL 20 drives feature a universal translate mode. In an AT/ EISA-class system, the drive may  
be configured to any specified combination of cylinders, heads and sectors (within the range of the drive's  
formatted capacity). DiamondMax VL 20 drives power-up in a translate mode:  
MODEL  
92041U4  
91531U3  
91021U2  
CYL  
HD  
16  
16  
16  
SPT  
63  
63  
LZone  
(*)  
(*)  
WPcom  
(*)  
MAX LBA  
40,020,624  
30,015,216  
20,010,816  
CAPACITY  
20,490 MB  
15,367 MB  
10,245 MB  
39,703  
29,777  
19,852  
(*)  
(*)  
63  
(*)  
(*) The fields LZone (Landing Zone) and WPcom (Write Pre-comp) are not used by the Maxtor hard drive  
and the values may be either 0 or the values set by the BIOS. All capacities listed in the above table are based  
on 106 or one million bytes.  
2 – 2  
PRODUCTDESCRIPTION  
Lo g ic a l Blo c k Ad d re s s in g  
The Logical Block Address (LBA) mode can only be utilized in systems that support this form of translation.  
The cylinder, head and sector geometry of the drive, as presented to the host, differs from the actual physical  
geometry. The host AT computer may access a drive of set parameters: number of cylinders, heads and  
sectors per track, plus cylinder, head and sector addresses. However, the drive can’t use these host parameters  
directly because of zoned recording techniques. The drive translates the host parameters to a set of logical  
internal addresses for data access.  
The host drive geometry parameters are mapped into an LBA based on this formula:  
LBA  
=
=
(HSCA - 1) + HHDA x HSPT + HNHD x HSPT x HCYA  
(HSCA - 1) + HSPT x (HHDA + HNHD x HCYA)  
(1)  
(2)  
where  
HSCA = Host Sector Address, HHDA = Host Head Address  
HCYA = Host Cylinder Address, HNHD = Host Number of Heads  
HSPT = Host Sectors per Track  
The LBA is checked for violating the drive capacity. If it does not, the LBA is converted to physical drive  
cylinder, head and sector values. The physical address is then used to access or store the data on the disk and  
for other drive related operations.  
De fe c t Ma n a g e m e n t Zo n e (DMZ)  
Each drive model has a fixed number of spare sectors per drive, all of which are located at the end of the  
drive. Upon detection of a bad sector that has been reassigned, the next sequential sector is used.  
For example, if sector 3 is flagged, data that would have been stored there is “pushed down” and recorded  
in sector 4. Sector 4 then effectively becomes sector 3, as sequential sectors are “pushed down” across the  
entire drive. The first spare sector makes up for the loss of sector 3, and so maintains the sequential order of  
data. This push down method assures maximum performance.  
On -t h e -Fly Ha rd w a re Erro r Co rre c t io n Co d e (ECC)  
5 symbols, single burst, guaranteed  
S o ft w a re ECC Co rre c t io n  
22 symbols, single burst, guaranteed  
Au t o m a t ic P a rk a n d Lo c k Op e ra t io n  
Immediately following power down, dynamic braking of the spinning disks delays momentarily allowing the  
read/ write heads to move to an inner mechanical stop. A small fixed magnet holds the rotary actuator in  
place as the disk spins down. The rotary actuator is released only when power is again applied.  
2 – 3  
PRODUCTDESCRIPTION  
Ca c h e Ma n a g e m e n t  
Bu ffe r S e g m e n t a t io n  
The data buffer is organized into two segments: the data buffer and the micro controller scratch pad.  
The data buffer is dynamically allocated for read and write data depending on the commands received.  
A variable number of read and write buffers may exist at the same time.  
Re a d -Ah e a d Mo d e  
Normally, this mode is active. Following a read request, disk read-ahead begins on the first sector and  
continues sequentially until the allocated buffer is full. If a read request is received during the read-ahead  
operation, the buffer is examined to determine if the request is in the cache. If a cache hit occurs, read-  
ahead mode continues without interruption and the host transfer begins immediately.  
Au t o m a t ic Writ e Re a llo c a t io n (AWR)  
This feature is part of the write cache and reduces the risk of data loss during deferred write operations. If a  
disk error occurs during the disk write process, the disk task stops and the suspect sector is reallocated to a  
pool of alternate sectors located at the end of the drive. Following reallocation, the disk write task continues  
until it is complete.  
Writ e Ca c h e S t a c k in g  
Normally, this mode is active. Write cache mode accepts the host write data into the buffer until the buffer  
is full or the host transfer is complete. A command complete interrupt is generated at the end of the transfer.  
A disk write task begins to store the host data to disk. Host write commands continue to be accepted and  
data transferred to the buffer until either the write command stack is full or the data buffer is full. The drive  
may reorder write commands to optimize drive throughput.  
2 – 4  
PRODUCTDESCRIPTION  
Ma jo r HDA Co m p o n e n t s  
Drive Me c h a n is m  
A brush-less DC direct drive motor rotates the spindle at 5,400 RPM (±0.1%). The dynamically balanced  
motor/ spindle assembly ensures minimal mechanical run-out to the disks. A dynamic brake provides a fast  
stop to the spindle motor upon power removal. The speed tolerance includes motor performance and motor  
circuit tolerances.  
Ro t a ry Ac t u a t o r  
All DiamondMax VL 20 drives employ a rotary voice coil actuator which consists of a moving coil, an  
actuator arm assembly and stationary magnets. The actuator moves on a low-mass, low-friction center shaft.  
The low friction contributes to fast access times and low power consumption.  
Re a d /Writ e Ele c t ro n ic s  
An integrated circuit mounted within the sealed head disk assembly (near the read/ write heads) provides up  
to eight head selection (depending on the model), read pre-amplification and write drive circuitry.  
Re a d /Writ e He a d s a n d Me d ia  
Low mass, low force giant magneto-resistive read/ write heads record data on 3.5-inch diameter disks. Maxtor  
uses a sputtered thin film medium on all disks for DiamondMax VL 20 drives.  
Air Filt ra t io n S ys t e m  
All DiamondMax VL 20 drives are assembled in a Class 100 controlled environment. Over the life of the  
drive, a 0.1 micron filter and breather filter located within the sealed head disk assembly (HDA) maintain a  
clean environment to the heads and disks. DiamondMax VL 20 drives are designed to operate in a typical  
office environment with minimum environmental control.  
M ic r o p r o c e s s o r  
The microprocessor controls the following functions for the drive electronics:  
Command execution  
Cache management  
Data correction and error recovery  
Diagnostic execution  
Data sequencing  
Head positioning (including error recovery)  
Host interface  
Index detection  
Spin speed control  
Se e ks  
Se rvo  
S.M.A.R.T.  
2 – 5  
PRODUCTDESCRIPTION  
S u b s ys t e m Co n fig u ra t io n  
Du a l Drive S u p p o rt  
Two drives may be accessed via a common interface cable, using the same range of I/ O addresses. The drives  
are jumpered as device 0 or 1 (Master/ Slave), and are selected by the drive select bit in the  
Device/ Head register of the task file.  
All Task File registers are written in parallel to both drives. The interface processor on each drive decides  
whether a command written to it should be executed; this depends on the type of command and which  
drive is selected. Only the drive selected executes the command and activates the data bus in response to  
host I/ O reads; the drive not selected remains inactive.  
A master/ slave relationship exists between the two drives: device 0 is the master and device 1 the slave.  
When J50 is closed (factory default, figure 2-1), the drive assumes the role of master; when open, the drive  
acts as a slave. In single drive configurations, J50 must be closed.  
Ca b le S e le c t Op t io n  
CSEL (cable select) is an optional feature per ANSI ATA specification. Drives configured in a multiple drive  
system are identified by CSEL’s value:  
– If CSEL is grounded, then the drive address is 0.  
– If CSEL is open, then the drive address is 1.  
J u m p e r Lo c a t io n /Co n fig u ra t io n  
Darkened jumper pins indicate factory-installed (default) shunts.  
+12 VDC  
+12 V return  
+5 V return  
+5 VDC  
JUMPER CONFIGURATION  
J50  
J48  
J46  
J44  
J42  
Master/Slave  
Only drive in single drive system*  
Master drive in dual drive system*  
Slave drive in dual drive system  
Cable Select  
Disabled*  
Enabled  
C
C
O
EIDE Interface Connector  
J1 – pin 1  
O
C
Cylinder Limitation  
Disabled*  
Enabled  
Power Connector  
O
C
J50 - Master/Slave  
J48 - Cable Select  
J2  
Factory Reserved  
Factory Reserved  
O
J46 - Cylinder Limitation  
J44 - Factory Reserved  
J42 - Factory Reserved  
O
Key * = Default C = Closed (jumper installed) O = Open (no jumper installed)  
Figure 2-1  
PCBA Jumper Location and Configuration  
Cylin d e r Lim it a t io n J u m p e r De s c rip t io n  
On some older BIOS', primarily those that auto-configure the disk drive, a hang may occur. The Cylinder  
Limitation jumper reduces the capacity in the Identify Drive allowing large capacity drives to work with older  
BIOS'. The capacity reported when J46 is closed will be as follows: drives less than or equal to 32GB will  
report 2.1GB. Drives greater than 32GB will report 32GB.  
2 – 6  
SECTION 3  
P ro d u c t S p e c ific a t io n s  
Mo d e ls a n d Ca p a c it ie s  
MODEL  
92041U4  
91531U3  
91021U2  
20,490  
15,367  
10,245  
Formatted Capacity (MB LBA Mode)  
Maxtor defines one megabyte as 106 or one million bytes and one  
gigabyte as 109 or one billion bytes.  
Drive Co n fig u ra t io n  
MODEL  
92041U4  
91531U3  
91021U2  
Integrated Controller / Interface  
Encoding Method  
Interleave  
ATA-5 / Ultra DMA  
E2 PR4 RLL 16/17  
1:1  
Servo System  
Embedded  
512 KB SDRAM  
16  
Buffer Size / Type  
Data Zones per Surface  
Data Surfaces / Heads  
Number of Disks  
Areal Density  
4
2
3
2
1
2
7,200 Mb / in2  
19,700 tpi  
298 - 354 kbpi  
317 - 377 kfci  
512  
Track Density  
Recording Density  
Flux Density  
Bytes per Sector / Block  
Sectors per Track  
Sectors per Drive  
336 - 624  
40,020,624 30,015,216 20,010,816  
P e rfo rm a n c e S p e c ific a t io n s  
MODEL  
92041U4  
91531U3  
91021U2  
Seek Times (typical)  
Track-to-Track  
1.0 ms  
9.5 ms  
Average  
Maximum  
< 20.0 ms  
5.55 ms  
Average Latency  
Rotational Speed (±0.1%)  
Controller Overhead  
Data Transfer Rate  
5,400 RPM  
< 0.3 ms  
To/From Interface  
up to 66.7 MB/sec  
up to 16.7 MB/sec  
(UltraDMA - M4)  
To/From Interface  
(PIO 4/Multi-word DMA - M4)  
To/From Media  
up to 36.9 MB/sec  
7.3 sec typical  
Start Time (0 to Drive Ready)  
3 – 1  
PRODUCTSPECIFICATIONS  
P h ys ic a l Dim e n s io n s  
PARAMETER  
Height  
Length  
Width  
Weight  
STANDARD  
1.02 inches  
5.78 inches  
4.00 inches  
1.3 pounds  
METRIC  
25.9 millimeters  
146.6 millimeters  
102.1 millimeters  
0.59 kilograms  
1.028 max  
[25.9 mm]  
.25 ± .01  
6 x 6-32  
UNC Tap  
1.638 ± .005  
[41.61 mm]  
1.122 ± .02  
[28.4 mm]  
4.000 ± .01  
[101.6 mm]  
5.787 max  
[146.6 mm]  
4 x 6-32  
UNC Tap  
1.75 ± .02  
1.625 ± .02  
4.00 ± .01  
[102.1 mm]  
3.75 ± .01  
[95.25 mm]  
Figure 3 - 1  
Outline and Mounting Dimensions  
3 – 2  
PRODUCTSPECIFICATIONS  
P o w e r Re q u ire m e n t s  
MODE  
12V ± 10%  
2100 mA  
740 mA  
295 mA  
230 mA  
20 mA  
5V ± 5%  
660 mA  
455 mA  
465 mA  
430 mA  
220 mA  
155 mA  
POWER  
Spin-up (peak)  
Seek (avg)  
11.1 W  
6.2 W  
4.9 W  
1.3 W  
0.9 W  
Read/Write (avg)  
Idle (avg)  
Standby (avg)  
Sleep (avg)  
20 mA  
P o w e r Mo d e De fin it io n s  
S p in -u p  
The drive is spinning up following initial application of power and has not yet reached full speed.  
S e e k  
A random access operation by the disk drive.  
Re a d /Wr it e  
Data is being read from or written to the drive.  
Id le  
The drive is spinning, the actuator is parked and powered off and all other circuitry is powered on.  
The drive is capable of responding to read commands within 40 ms.  
S t a n d b y  
The spin motor is not spinning. The drive will leave this mode upon receipt of a command that requires  
disk access. The time-out value for this mode is programmable. The buffer is active to accept write data.  
S le e p  
This is the lowest power state – with the interface set to inactive. A software or hardware reset is required  
to return the drive to the Standby state.  
EP A En e rg y S t a r Co m p lia n c e  
Maxtor Corporation supports the goals of the U.S. Environmental Protection Agency’s Energy Star program  
to reduce the electrical power consumption of computer equipment.  
En viro n m e n t a l Lim it s  
PARAMETER  
OPERATING  
NON-OPERATING/STORAGE  
Temperature  
5° C to 55° C  
low temperature (-40° C)  
high temperature (71° C) per MIL-STD-810E, method 501.3,  
climatic category; hot-induced conditions.  
Thermal Gradient  
Relative Humidity  
Wet Bulb  
25° C per hour (maximum)  
5% to 95% (non-condensing)  
27° C (maximum)  
Altitude  
-200 to 10,000 feet  
-200 to 40,000 feet  
Acoustic Noise (Idle mode)  
3.3 bel average sound power  
(per ISO 7779, 10 microphone)  
3 – 3  
PRODUCTSPECIFICATIONS  
S h o c k a n d Vib ra t io n  
PARAMETER  
OPERATING  
NON-OPERATING  
Mechanical Shock  
Rotational Shock  
Random Vibration  
30 Gs, 2.0 ms, no errors  
250 Gs, 2.0 ms, no damage  
18,000 Rad/sec,0.5 - 1.0 ms, no damage  
10 - 2,000 Hz at 2.15 Grms, no damage  
10 - 45 Hz at 0.004 G2/Hz  
48 - 62 Hz at 0.008 G2/Hz  
65 - 300 Hz at 0.004 G2/Hz  
301 - 500 Hz at 0.0006 G2/Hz  
no errors  
Swept Sine Vibration  
5 - 20 Hz  
21 - 300 Hz  
0.049 inches double amplitude  
1.0 G peak amplitude (0 - peak)  
Re lia b ilit y S p e c ific a t io n s  
An n u a l Re t u rn Ra t e  
< 1.0%  
Annual Return Rate (ARR) indicates the average against products  
shipped. ARR includes all reasons for returns (failures, handling  
damage, NDF), but does not include inventory credit returns.  
Qu a lit y Ac c e p t a n c e Ra t e  
< 500 DPPM  
The quality acceptance rate indicates the percentage of Maxtor  
products successfully installed by our customers, and/ or the number  
of defective parts per million (DPPM) encountered during the entire  
installation process.  
S t a rt /S t o p Cyc le s  
50,000 (minimum)  
This indicates the minimum cycles for reliable start/ stop function at a  
60% confidence level.  
Da t a Re lia b ilit y  
< 1 per 1014 bits read  
Data errors (non-recoverable). Average data error rate allowed with all  
error recovery features activated.  
Co m p o n e n t De s ig n Life  
5 years (minimum)  
Component design life is defined as a.) the time period before  
identified wear-out mechanisms impact the failure rate, or b.) the time  
period up to the wear-out point when useful component life expires.  
3 – 4  
PRODUCTSPECIFICATIONS  
EMC/EMI  
Ra d ia t e d Ele c t ro m a g n e t ic Fie ld Em is s io n s - EMC Co m p lia n c e  
The hard disk drive mechanism is designed as a subassembly for installation into a suitable enclosure and is  
therefore not subject to Subpart J of Part 15 of FCC Rules (47CFR15) or the Canadian Department of  
Communications Radio Interference Regulations. Although not required, the disk mechanism has been  
tested within a suitable end-use product and found to comply with Class B limits of the FCC Rules and  
Regulations of the Canadian Department of Communications.  
The CE Marking indicates conformity with the European Union Low Voltage Directive (73/ 23/ EEC) when  
the disk mechanism is installed in a typical personal computer. Maxtor recommends that testing and analysis  
for EMC compliance be performed with the disk mechanism installed within the user's end-use application.  
Ca n a d ia n Em is s io n s S t a t e m e n t  
This digital apparatus does not exceed the Class B limits for radio noise emissions from digital apparatus as set  
out in the radio interference regulations of the Canadian department of communications.  
Le present appareil numerique n'emet pas de bruit radioelectriques depassant les limites applicables aux  
appareils numeriques de Class B prescrites dans le reglement sur le brouillage radioelectrique edicte par le  
ministere des communications du Canada.  
S a fe t y Re g u la t o ry Co m p lia n c e  
All Maxtor hard drives comply with relevant product safety standards such as CE, CUL, TUV and UL rules and  
regulations. As delivered, Maxtor hard drives are designed for system integration before they are used.  
3 – 5  
SECTION 4  
Ha n d lin g a n d In s t a lla t io n  
P re -fo rm a t t e d Drive  
This Maxtor hard drive has been formatted at the factory. Do not use a low-level formatting program.  
Ha rd Drive Ha n d lin g P re c a u t io n s  
If the handling precautions are not followed, damage to the hard drive may result - which may void the warranty.  
During handling, NEVER drop, jar, or bump a drive. Handle the drive by its sides and avoid touching the printed circuit  
board assembly (PCBA).  
Hard drives are sensitive to electrostatic discharge (ESD) damage. Use proper ESD practices by grounding yourself  
and the computer system the hard drive will be installed in.  
Allow the hard drive to reach room temperature BEFORE installing it in your computer system.  
NEVER switch DC power onto the drive by plugging an electrically live DC source cable into the drive's connector.  
NEVER connect a live connector to the hard drive's IDE interface connector.  
Ele c t ro -S t a t ic Dis c h a rg e (ES D)  
To avoid some of the problems associated with ESD, Maxtor advises that anyone handling a disk drive use a  
wrist strap with an attached wire connected to an earth ground. Failure to observe these precautions voids the  
product warranty.  
Manufacturers frequently experience “unsolved” component/ hardware malfunctions often caused by ESD. To  
reduce the incidence of ESD-related problems, Maxtor recommends that any electronics manufacturing plans  
include a comprehensive ESD program, the basic elements and functions of which are outlined here:  
ESD Program Element  
Management  
Chief coordinator  
Multi-department committee  
Employee training  
ESD Program Function  
Institute and maintain  
Organize and enforce  
Evaluate and improve  
Educate and inform  
ESD program supplies typically include: wrist- and foot-worn grounding straps; counter-top and floor antistatic  
matting; wrist strap testers; ESD video and training materials. Sources for such supplies include:  
Static Control Systems – 3M  
225-4S, 3M Center  
Charleswater  
93 Border St.  
St. Paul, MN 55144  
West Newton, MA 02165-9990  
Maxtor also offers a complete video training package, “Care and Handling of Maxtor Disk Drives.”  
Contact your Maxtor representative for details.  
4 – 1  
INSTALLATION  
Un p a c k in g a n d In s p e c t io n  
Retain any packing material for reuse. Inspect the shipping container for evidence of damage in transit. Notify  
the carrier immediately in case of damage to the shipping container.  
As they are removed, inspect drives for evidence of shipping damage or loose hardware. If a drive is damaged  
(and no container damage is evident), notify Maxtor immediately for drive disposition.  
Figure 4 - 1  
Multi-pack Shipping Container  
4 – 2  
INSTALLATION  
Figure 4 - 2  
Single Pack Shipping Container (Option A)  
Figure 4 - 3  
Single Pack Shipping Container (Option B)  
Re p a c k in g  
If a Maxtor drive requires return, repack it using Maxtor packing materials, including the antistatic bag.  
P h ys ic a l In s t a lla t io n  
Re c o m m e n d e d Mo u n t in g Co n fig u ra t io n  
The DiamondMax® drive design allows greater shock tolerance than that afforded by larger, heavier drives.  
The drive may be mounted in any attitude using four size 6-32 screws with 1/ 8-inch maximum penetration  
and a maximum torque of 5-inch pounds. See Figure 3-1 for mounting dimensions. Allow adequate  
ventilation to the drive to ensure reliable operation.  
4 – 3  
INSTALLATION  
1 Be fo re Yo u Be g in  
IMP ORTANT – P LEAS E READ!  
Please read this Installation Sheet completely before installing the Maxtor hard drive. It gives general information for installing a Maxtor hard drive in a  
typical computer system.  
If you don’t understand the installation steps, have a qualified computer technician install the hard drive.  
Ha n d lin g P re c a u t io n s  
If the handling precautions are not followed, damage to the hard drive may result - which may void the warranty.  
Allow the hard drive to reach room temperature BEFORE installing it in your computer system.  
Hard drives are sensitive to electrostatic discharge (ESD) damage.  
Handle the drive by its sides. DO NOT touch the printed circuit board assembly.  
NEVER drop, jar, or bump the drive.  
DON’T connect/disconnect any drive cables when the power is on.  
DON’T useanylow-levelformattingsoftwareonthisdrive.  
S ys t e m Re q u ire m e n t s  
IDE/ATinterface  
Foroptimalperformance,Maxtorrecommends:  
Pentium-class processor  
Windows95orhigher  
UltraDMAcapablesystem  
To o ls fo r In s t a lla t io n  
The following tools are needed to complete the installation of your Maxtor hard drive:  
A small Phillips head screw driver  
Your computer user’s manual  
Small needle-nose pliers or  
tweezers  
Operating system software  
Drive Id e n t ific a t io n In fo rm a t io n  
Copy the following information from the label on the top cover of the Maxtor hard drive for future reference:  
Model Number _____________________ Serial Number _____________________  
Cylinders ______________ Heads _____________ Sectors _______________  
HDA Uplevel ______________ PCBA Uplevel _____________ Unique Uplevel _______________  
Ca p a c it y Ba rrie rs  
Due to operating system limitations, DOS cannot access the full capacity of drives larger than 8.4 GB. The Microsoft Windows 95 operating system or  
equivalent (full installation), NOT a Windows 95 upgrade from DOS (Windows 3.1 or 3.11), is required to obtain the full capacity of any hard drive larger  
than 8.4 GB.  
P ro t e c t in g Yo u r Exis t in g Da t a  
Periodicbackupofimportantdataisalwaysagoodidea.Wheneveryourcomputerison,thereisthepotentialforlosingdataonyourharddrive.Thisisespeciallytruewhenrunning  
diskutilitiesoranysoftwarethatdirectlymanipulatesyourfiles.Maxtorrecommendsthatyoumake a backupcopyofthefilesonanyexistingharddrives.Ifrequired,this  
datamaythenbecopiedtotheMaxtorharddriveafterithasbeeninstalledinyourcomputer.Refertoyourcomputeruser’smanualfordetaileddatabackupinstructions.  
4 – 4  
INSTALLATION  
2 Ge n e ra l Re q u ire m e n t s  
S ys t e m Ha rd w a re Re q u ire m e n t s  
The minimum system Maxtor recommends for drives 8.4 GB or less is a 486 DX 66 MHz system. For drives larger than 8.4 GB, we recommend a  
Pentium-classsystem.  
BIOS Re q u ire m e n t s  
SystemBIOSdatedpriortoSeptember1997donotsupportdrivesgreaterthan8.4GB.Toobtainthefullcapacityofadrivelargerthan8.4GB,upgradetheBIOS,installaBIOS  
enhancercardorusetheMaxBlastinstallationsoftware(version9.06ornewer).  
Ult ra Dire c t Me m o ry Ac c e s s (UDMA)  
UDMA mode on a Maxtor hard drive will only activate when the drive is installed in a system with full UDMA capability, i.e., a mother board or interface card  
with the UDMA chips and the associated UDMA software drivers.  
OS Re q u ire m e n t s fo r La rg e Ca p a c it y Ha rd Drive s  
A full installation of the Windows 95 operating system is required for hard drives larger than 8.4 GB when the drive is a Primary Master. An upgrade to  
Windows 95 from Windows 3.11 and/or the DOS operating system will not support drive capacities greater than 8.4 GB when the drive is a Primary Master.  
3 Ha rd Drive Id e n t ific a t io n  
IDE stands for Integrated Drive Electronics and EIDE is Enhanced IDE. The IDE or EIDE interface is designed to support two devices – typically hard drives – on a  
single ribbon cable through one 40 pin connector on the mother board or interface card.  
Some mother boards and interface cards may have a second IDE/EIDE connector to support two additional IDE devices. The IDE/EIDE interface is identified as  
a primary or secondary interface. In systems with only a single connector on the mother board or interface card, it is the primary IDE/EIDE interface. To add a  
second IDE/EIDE interface requires a special interface card. In systems with two connectors on the mother board or interface card, one is the primary and the  
other as the secondary.  
The primary interface must be used for at least one IDE device before connecting any devices to the secondary IDE interface.  
Ribbon cable lengths are limited to 18 inches and have two or three 40 pin connectors. This cable is referred to as a parallel cable and IDE devices may be  
connected anywhere on the cable. One of the connectors is attached to the IDE connector on the mother board or interface card and the remaining  
connector(s) are available for the IDE devices.  
Id e n t ifyin g IDE De vic e s o n t h e In t e rfa c e  
Each device must be identified as either the Master or Slave device on that interface (cable). Each cable must have a Master before it can have a Slave device  
on the cable. There cannot be two Master or two Slave devices on the same cable.  
IDE devices use jumpers to designate the Master/Slave identification of the device. Each manufacturer may have its own jumpering scheme to identify the  
device as a Master or Slave and its relationship to other IDE devices attached to the same cable.  
J u m p e r S e t t in g s  
A jumper is a small piece of plastic that slides over a pair of configuration pins on the drive to activate a specific function. The jumper illustration below shows  
three valid jumper settings for Maxtor hard drives – Master, Slave and Cable Select. Maxtor hard drives can be set as either a Master or a Slave device.  
There are no other jumpers to set when the Maxtor drive is installed on the same ribbon cable with another IDE device.  
Rear View of Maxtor Hard Drive  
Master, Slave and Cable Select Settings  
4 – 5  
INSTALLATION  
Before installing the drive in the computer, you must determine how the jumpers on the Maxtor hard drive are to be set for your system based upon the use of  
the Maxtor hard drive as either a Master or Slave device. Maxtor hard drives are shipped with the Master jumper setting enabled.  
IMPORTANT: If a Maxtor hard drive is being added to a system on the same cable with an existing IDE device, it may be necessary to re-configure the  
jumpers on the existing device to insure that the system will properly recognize both devices. Information regarding the correct jumper configurations on other  
IDE devices is available in their product documentation or from the manufacturer of that device.  
S ys t e m s Us in g Ca b le S e le c t  
IMPORTANT Most systems do not use this feature. Unless you are sure that your computer system supports Cable Select, do not set up the drive with this  
feature enabled.  
Maxtor hard drives support Cable Select. The Cable Select method of drive identification allows the system to identify Master and Slave IDE devices based  
upon the position (connector) the IDE device is attached to on the interface (ribbon) cable.  
A special IDE cable select interface (ribbon) cable is required for systems using the Cable Select feature.  
Systems that use Cable Select do not support the standard Master/Slave definitions described above and the standard IDE interface (ribbon) cable cannot  
be used on these systems. If your system supports this feature, refer to the system user’s manual or contact the system manufacturer for specific procedures  
for installing hard drives.  
On Maxtor hard drives, Cable Select is enabled by installing a jumper on J48.  
Re la t io n s h ip t o Ot h e r IDE De vic e s  
Maxtor recommends that its hard drives be configured as a Master device to any IDE device that is not a hard drive (e.g., CD-ROM’s, Tape drives, Zip Drives  
etc.).  
4 Mo u n t in g Drive in S ys t e m  
Turn the computer OFF, disconnect the power cord and remove the cover. Refer to the computer user’s manual for information on removing the cover.  
Each system manufacturer uses different types of cases, including desktop, mini-tower, full tower and other special configurations. As a result, there are many  
different possible mounting locations that could be used.  
In a typical system case, there are specific 3.5 inch and 5.25 inch bays available for storage devices. When a 3.5 inch mounting bay is available, mounting  
brackets are not required. If a 5.25 inch mounting bay is used, mounting brackets will be required to mount the Maxtor hard drive in the system case. Refer to  
the system manufacturers user’s manual or contact the system manufacturer directly for additional information.  
In s t a llin g 5 .2 5 -in c h Mo u n t in g Bra c k e t s a n d Ra ils  
If the Maxtor hard drive is being mounted in a 5.25 inch drive bay, the following figure shows how to attach the brackets to the drive. The brackets are not  
required when mounting in a 3.5 inch drive bay.  
In s t a llin g in a De vic e Ba y  
After the hard drive is prepared with mounting brackets, if required, and the jumpers are set correctly, the drive can be mounted in a device bay and secured.  
Be sure to secure the drive with all four screws in the device bay. This provides grounding and protection from shock and vibration.  
NOTE:Computersystemsusedifferentmethodsformountingharddrives.Pleaserefertothecomputeruser’smanualorcontactthemanufacturerforspecificmounting  
instructions.  
4 – 6  
INSTALLATION  
5 At t a ch in g In t e rfa c e a n d Po w e r Ca b le s  
In order for the computer to recognize that the Maxtor hard drive is in the system, the power cable and IDE interface cable must be properly connected.  
1
Attach an available IDE interface connector to J1 on the Maxtor hard drive.  
The striped or colored edge of the IDE interface cable indicates pin 1. Pin 1 on the IDE interface cable connector must match pin 1 on the Maxtor hard drive  
IDE interface connector – closest to the drive power connector. It must also match pin 1 on the IDE connector on the mother board or IDE interface card.  
Refer to the system or interface card user’s manual for identification of pin 1 on their IDE interface connector.  
2
Connect an available power connector to J2 on the Maxtor hard drive. This connector is keyed and will only fit in one orientation.  
Do not force the connector.  
After attaching the IDE interface cable and the power cable  
to the Maxtor hard drive, verify that all other cables  
connected to other devices, the mother board or interface  
card(s) are correctly seated.  
Striped/colored edge is pin  
6 At t a ch in g S ys t e m Ca b le s  
The computer system the Maxtor hard drive is being installed in will have its own cable placement and connection methods. This means that the location of  
the IDE interface connectors on the mother board and/or interface card and the orientation of pin one is determined by the manufacturer. Also, older systems  
and interface cards may have only a single IDE interface connection – limiting the system to two IDE devices. Refer to the system or interface card user’s  
manual for cable connection and orientation instructions.  
Attach the 40-pin IDE interface cable from the Maxtor hard drive to the IDE connector on the mother board or IDE interface card. Insure that the red edge of  
the ribbon cable is oriented to pin 1 on the interface.  
NOTE: When installing a UDMA 66 DiamondMax Hard Drive (model numbers designated with a “U), an 80 conductor cable must  
be used. Please use the following connection steps; 1) the blue connector must be attached to the system IDE interface; 2) the gray  
connector must be attached to Device 1 (slave), and 3) the black connector must be attached to Device 0 (master).  
Striped Edge (Pin 1)  
Drive 1 - Slave (gray)  
Drive 0 - Master (black)  
System Connector (blue)  
4 – 7  
INSTALLATION  
7 S ys t e m S e t u p  
The following procedures are designed for systems using the DOS 5.0 (or higher), Windows 95 and Windows 98 operating systems. For other operating  
systems (e.g., Windows NT, OS2, UNIX, LINUX and NovellNetWare), refer to the operating system user’s manual for the BIOS setting and other installation  
requirements.  
For drives with capacities larger than 8.4 GB, the full installation set for Windows 95A or 95B (OSR2), Windows 98 or equivalent, is required. Operating systems  
that do not support extended interrupt 13 cannot access or format a drive larger than 8.4 GB. This is true regardless of BIOS, mother board or interface card  
support. DOS based operating systems do not support this interrupt and are limited to a maximum drive size that they can format and access of 8.4 GB. It is not  
possible to upgrade from a DOS operating system to Windows 95 and obtain the full capacity of a drive larger than 8.4 GB.  
S e t t in g t h e BIOS (CMOS )  
The SETUP (BIOS) program identifies the system configuration information (e.g., floppy disk drives, hard disk drives, video, etc.) used to identify devices  
attached to the computer during system boot. This includes the information about what kind and how many IDE hard drives are attached to the system.  
IMPORTANT: Please Note – Major BIOS manufacturers like AMI, Award and Phoenix provide their core BIOS programs to system board manufacturers and  
OEM’s who have the capability of making modifications to some of the descriptions and definitions to meet their unique requirements. These changes include,  
but are not limited to, how to access the BIOS, the appearance of the information on the screens and the location of parameters within the BIOS. Refer to the  
system or BIOS manufacturers documentation or contact the system manufacturer for the correct procedure to enter the BIOS setup program for your  
computer. Some manufacturers may use their own unique BIOS definitions and configurations and will also have their own methods for accessing and setting  
the BIOS. If you have a system that uses such a unique BIOS, refer to the system user’s manual or contact the manufacturer for assistance.  
WARNING: When entering settings for the Maxtor hard drive, be careful not to change any of the other BIOS settings, or other parts of  
the system may not work correctly.  
BIOS (CMOS ) P a ra m e t e rs  
In order for the computer system to recognize the new Maxtor hard drive, it is necessary to set the system BIOS with the correct information about the drive.  
To do this, run the system SETUP (BIOS) program.  
The Maxtor hard drive must be identified to the system through the BIOS and it must be registered in the BIOS based upon its position relative to the other IDE  
devices connected to the system and recorded in the BIOS.  
Most newer BIOS’ provide the descriptions of Primary Master, Primary Slave, Secondary Master and Secondary Slave (see section 2) which identify the  
device configuration and location on an IDE interface and its relationship to the other IDE devices on the same interface or ribbon cable.  
Some older BIOS versions do not use this terminology for identification and it may be necessary to refer to the system user’s manual or BIOS documentation to  
determine where the drive settings should be set in that specific BIOS. If this information is not available, then it will be necessary to contact the system  
manufacturer for the correct terminology to correctly identify the drives within the system.  
The following are the typical steps to be used to set the hard drive parameters in a BIOS:  
A Turn the system ON. During the system start-up sequence, run the SETUP (BIOS) program or similar commands to access the system BIOS.  
Note: Newer systems will typically display a message (e.g., press DEL to Enter Setup) identifying how to access the SETUP (BIOS) program.  
B
Once the SETUP (BIOS) program is active, do one of the following to set the BIOS parameters for the Maxtor hard drive.  
1
Enter the BIOS menu where the hard drive settings are displayed, select the correct entry (Primary Master, Primary Slave, Secondary Master or  
Secondary Slave or their equivalents) to set the parameters for the Maxtor hard drive.  
If the SETUP program provides an “AUTO DETECT” capability, use this feature to detect the Maxtor hard drive. If the SETUP program does not have  
AUTO DETECT, set the drive parameters as defined in step 2. Typically, this feature is available for each individual IDE device. It may be necessary to  
exit the BIOS, re-boot the system and re-enter the BIOS before the AUTO DETECT operation will take effect.  
IMPORTANT After the SETUP program has detected the hard drive, verify that the Logical Block Addressing (LBA) mode is enabled for the drive - as  
not all BIOS versions set this feature during the AUTO DETECT process.  
Comment: When LBA is enabled, some BIOS programs (typically Award) will change the values of the cylinders and heads by dividing the cylinders by  
2, 4, 8 or 16 and multiplying the heads by the same value. This operation will not change the capacity of the hard drive.  
If the system correctly detects the drive and does not hang during the boot process, proceed to Section 8. If the system hangs during the POST,  
proceed to Section 9. If Auto Detect did not find the drive and no error message was presented, proceed to step 2 below.  
2
Enter the BIOS menu where the hard drive definitions are displayed and select the appropriate entry (Primary Master, Primary Slave, Secondary  
Master or Secondary Slave – or their equivalents) for the Maxtor hard drive. If the SETUP program does not provide an AUTO DETECT capability, the  
4 – 8  
INSTALLATION  
drive parameters must be set using the User Definable Type (UDT).  
Set the Cylinder, Head and Sector values with the values listed on the drive label. The drive label is located on the top cover of the drive. The fields  
LZone (Landing Zone) and WPcom (Write Pre-comp) are not used by the Maxtor hard drive. These fields may be set to 0 or by the values assigned by  
the BIOS.  
Note: Each BIOS manufacturer uses different methods of identifying the UDT. Newer BIOS’ from all manufacturer’s will usually include an entry called  
User” or “User 1.” Older BIOS’ vary in the method used to identify the UDT. Following are examples of BIOS UDT: AMI = Type 47, Award = Type 47 and  
Phoenix = Type 48  
Only the cylinder, head and sector values printed on the drive label must be entered. All other values may be zero (0). Set the LBA mode to enabled for this  
drive. Refer to the system users manual or contact the system manufacturer for information on enabling LBA.  
If the SETUP program does not provide the UDT, set the BIOS to the drive type with the largest capacity of those listed in the BIOS.  
C
After the drive parameters are entered, follow the SETUP program procedures to save the settings and exit the SETUP program. After changing BIOS  
settings, saving the values and exiting, the SETUP program should force the system to re-boot.  
If you are not sure how the UDT is defined in the BIOS, refer to the computer user’s manual or contact the system manufacturer.  
8 Ha rd Drive P re p a ra t io n  
To finish the installation, the drive must be partitioned and formatted. Hard drive partitioning and formatting may be done with the operating system software  
or with MaxBlast installation software. Select A or B below to complete the preparation of the Maxtor hard drive.  
NOTE:Drive letter assignment is controlled by the operating system and not by the BIOS or MaxBlast. The operating system assigns drive letters to all devices  
as follows: (1) to all hard drives and their partitions; (2) to all other devices like CD-ROM’s and tape drives. When adding an additional hard drive to the system,  
the drive letters will be automatically changed by the operating system.  
A Preparing the hard drive using the operating system software.  
IMPORTANT Due to operating system limitations, DOS operating systems cannot access the full capacity of drives larger than 8.4 GB. The Windows 95 full  
installation, not an upgrade from DOS, operating system or equivalent is required to obtain the full capacity of any drive larger than 8.4 GB.  
If the system or interface card correctly supports the Maxtor hard drive, the drive may be partitioned and formatted using the operating system software. If the  
cylinder limitation jumper (J46) is installed or the BIOS does not support the hard drive, the MaxBlast installation software (option B below) must be used to  
prepare the hard drive.  
NOTE:All versions of DOS, PC-DOS, DR-DOS and Windows 95A (FAT 16 support) have a partition size limitation of 2.1 GB. For drives larger than 2.1 GB, the  
drive must be divided into partitions that do not exceed the 2.1 GB limitation. Windows 95B (OSR2) does not have this limitation. Windows NT, OS2, UNIX,  
LINUX and Novell NetWare may have different limitations but please refer to their documentation or contact the manufacturer to verify their support or  
limitations.  
For detailed operating system installation assistance, refer to the system manufacturers user’s manual, the operating system user’s manual or contact the  
manufacturer directly.  
B
Preparing the hard drive using MaxBlast installation software.  
1
2
Boot the system with the bootable MaxBlast software installation diskette.  
The MaxBlast installation software will load and the first screen of the program will display. Follow the on-screen prompts to complete the hard drive  
installation.  
4 – 9  
INSTALLATION  
9 S ys t e m Ha n g s Du rin g Bo o t  
If the system hangs during the boot process after installing the Maxtor hard drive – either before or after setting the system BIOS – the system many have a  
BIOS with a cylinder limitation. This may occur for hard drives that exceed 2.1 GB. If this happens,  
do the following:  
1
2
Turn the system OFF.  
Install the cylinder limitation jumper (J46) on the drive. The figure below shows the Maxtor hard drive configured as a Master or Slave device with the  
cylinderlimitationjumperinstalled.  
IMPORTANT: When the Cylinder Limitation jumper (J46) is installed, the Maxtor hard drive must be prepared using MaxBlast installation software.  
Certain OS's (e.g., Windows NT, Novell) do not support this option. You will have to install the drive on a system that has a BIOS that supports the capacity  
of the drive when installing these OS's.  
3
If the BIOS was set to AUTO DETECT, follow the instructions in Section 7 to prepare the hard drive using the MaxBlast installation software.  
IfotherBIOSsettingswereused,accessthesystemBIOSSETUPprogramandsettheparameterstoaUserDefinableTypewith4,092cylinders,16headsand63  
sectorspertrackfortheMaxtorharddrive.ThenfollowtheinstructionsforsettingtheBIOSinSection7thenSection8topreparetheharddrivewithMaxBlastsoftware.  
4 – 10  
SECTION 5  
AT In t e rfa c e De s c rip t io n  
In t e rfa c e Co n n e c t o r  
All DiamondMax® VL 20 AT drives have a 40-pin ATA interface connector mounted on the PCBA. The drive  
may connect directly to the host; or it can also accommodate a cable connection (max cable length:  
18 inches).  
Striped Edge (Pin 1)  
Drive 1 - Slave (gray)  
Drive 0 - Master (black)  
System Connector (blue)  
Figure 5-1  
Data Connector  
P in De s c rip t io n S u m m a ry  
PIN  
01  
03  
05  
07  
09  
11  
SIGNAL  
PIN  
02  
04  
06  
08  
10  
12  
14  
16  
18  
20  
22  
24  
26  
28  
30  
SIGNAL  
Reset -  
Ground  
DD8  
DD7  
DD6  
DD9  
DD5  
DD10  
DD4  
DD11  
DD3  
DD12  
DD13  
DD14  
DD15  
(keypin)  
Ground  
Ground  
Ground  
CSEL  
13  
15  
17  
19  
21  
23  
25  
27  
29  
DD2  
DD1  
DD0  
Ground  
DMARQ  
DIOW -:STOP  
DIOR -:HDMARDY:HSTROBE  
IORDY:DDMARDY:DSTROBE  
DMACK -  
Ground  
IOCS16  
Obsolete  
31  
INTRQ  
32  
33  
35  
37  
39  
DA1  
DA0  
34  
36  
38  
40  
PDIAG -  
DA2  
CS0 -  
DASP -  
CS1 -  
Ground  
5 – 1  
AT INTERFACEDESCRIPTION  
P in De s c rip t io n Ta b le  
PIN NAME  
RESET -  
DD0  
PIN  
I/O SIGNAL NAME  
SIGNAL DESCRIPTION  
01  
I
Host Reset  
Reset signal from the host system. Active during power up and inactive after.  
17  
I/O Host Data Bus  
16 bit bi-directional data bus between host and drive. Lower 8 bits used for register  
and ECC byte transfers. All 16 bits used for data transfers.  
DD1  
DD2  
15  
13  
11  
09  
07  
05  
03  
04  
06  
08  
10  
12  
14  
16  
18  
21  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
DD3  
DD4  
DD5  
DD6  
DD7  
DD8  
DD9  
DD10  
DD11  
DD12  
DD13  
DD14  
DD15  
DMARQ  
O
DMA Request  
Host I/O Write  
Host I/O Read  
This signal is used with DMACK for DMA transfers. By asserting this signal, the  
drive indicates that data is ready to be transfered to and from the host.  
DIOW -  
STOP  
23  
25  
I
Rising edge of Write strobe clocks data from the host data bus to a register on the  
drive.  
DIOR -  
HDMARDY  
I
Read strobe enables data from a register on the drive onto the host data bus.  
DMA ready during UltraDMA data in bursts.  
Data strobe during UltraDMA data out bursts.  
HSTROBE  
IORDY  
DDMARDY  
-
27  
O
I/O Channel Ready  
Cable Select  
This signal may be driven low by the drive to insert wait states into host I/O cycles.  
DMA ready during UltraDMA data out bursts.  
Data strobe during UltraDMA data in bursts.  
DSTROBE  
CSEL  
DMACK -  
INTRQ  
28  
29  
31  
Used for Master/Slave selection via cable. Requires special cabling on host system  
and installation of Cable Select jumper.  
I
DMA Acknowledge This signal is used with DMARQ for DMA transfers. By asserting this signal, the  
host is acknowledging the receipt of data or is indicating that data is available.  
O
Host Interrupt  
Request  
Interrupt to the host asserted when the drive requires attention from the host.  
IOCS16  
PDIAG -  
DA0  
32  
34  
35  
33  
36  
37  
Device 16 bit I/O  
Obsolete  
I/O Passed Diagnostic  
Output by drive when in Slave mode; Input to drive when in Master mode.  
3 bit binary address from the host to select a register in the drive.  
I
I
I
I
Host Address Bus  
DA1  
DA2  
CS0 -  
Host Chip Select 0  
Host Chip Select 1  
Chip select from the host used to access the Command Block registers in the drive.  
This signal is a decode of I/O addresses 1F0 - 1F7 hex.  
CS1 -  
DASP -  
GND  
38  
39  
I
Chip select from the host used to access the Control registers in the drive. This  
signal is a decode of I/O addresses 3F6 - 3F7 hex.  
I/O Drive Active/Drive 1 Time-multiplexed, open collector output which indicates that a drive is active, or that  
Present  
device 1 is present.  
02  
19  
22  
24  
26  
30  
40  
20  
N/A Ground  
Signal ground.  
KEY  
N/A Key  
Pin used for keying the interface connector.  
5 – 2  
AT INTERFACEDESCRIPTION  
P IO Tim in g  
TIMING PARAMETERS  
MODE 0  
MODE 1  
MODE 2  
MODE 3  
MODE 4  
t0  
Cycle Time (min)  
600 ns  
70 ns  
383 ns  
50 ns  
240 ns  
30 ns  
180 ns  
30 ns  
80 ns  
70 ns  
30 ns  
10 ns  
20 ns  
5 ns  
120 ns  
25 ns  
70 ns  
25 ns  
20 ns  
10 ns  
20 ns  
5 ns  
t1  
Address valid to DIOR-/DIOW- setup (min)  
DIOR-/DIOW- 16-bit (min)  
DIOR-/DIOW- recovery time (min)  
DIOW- data setup (min)  
t2  
165 ns  
125 ns  
100 ns  
t2i  
t3  
60 ns  
30 ns  
50 ns  
5 ns  
45 ns  
20 ns  
35 ns  
5 ns  
30 ns  
15 ns  
20 ns  
5 ns  
t4  
DIOW- data hold (min)  
t5  
DIOR- data setup (min)  
t6  
DIOW- data hold (min)  
t6Z  
t9  
DIOR- data tristate (max)  
DIOR-/DIOW- to address valid hold (min)  
Read Data Valid to IORDY active (min)  
IORDY Setup Time  
30 ns  
20 ns  
0
30 ns  
15 ns  
0
30 ns  
10 ns  
0
30 ns  
10 ns  
0
30 ns  
10 ns  
0
tRd  
tA  
tB  
35 ns  
1250 ns  
35 ns  
1250 ns  
35 ns  
1250 ns  
35 ns  
1250 ns  
35 ns  
1250 ns  
IORDY Pulse Width (max)  
Figure 5 - 2  
PIO Data Transfer To/From Device  
5 – 3  
AT INTERFACEDESCRIPTION  
DMA Tim in g  
TIMING PARAMETERS  
MODE 0  
MODE 1  
MODE 2  
t0  
Cycle Time (min)  
480 ns  
150 ns  
120 ns  
tC  
tD  
tE  
DMACK to DMARQ delay  
DIOR-/DIOW- (min)  
215 ns  
150 ns  
5 ns  
80 ns  
60 ns  
5 ns  
70 ns  
DIOR- data access (min)  
tF  
DIOR- data hold (min)  
5 ns  
20 ns  
10 ns  
0
tG  
tH  
tI  
DIOR-/DIOW- data setup (min)  
DIOW- data hold (min)  
100 ns  
20 ns  
0
30 ns  
15 ns  
0
DMACK to DIOR-/DIOW- setup (min)  
DIOR-/DIOW- to DMACK hold (min)  
DIOR- negated pulse width (min)  
DIOW- negated pulse width (min)  
DIOR- to DMARQ delay (max)  
DIOW- to DMARQ delay (max)  
DMACK- to tristate (max)  
tJ  
20 ns  
50 ns  
215 ns  
120 ns  
40 ns  
20 ns  
5 ns  
5 ns  
tKr  
tKw  
tLr  
tLw  
tZ  
50 ns  
50 ns  
40 ns  
40 ns  
25 ns  
25 ns  
25 ns  
35 ns  
35 ns  
25 ns  
Figure 5 - 3  
Multi-word DMA Data Transfer  
5 – 4  
AT INTERFACEDESCRIPTION  
Ult ra DMA Tim in g  
TIMING PARAMETERS (all times in nanoseconds)  
MODE 0  
MODE 1  
MODE 2  
MODE 3  
MODE 4  
MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX  
tCYC  
Cycle Time (from STROBE edge to STROBE edge)  
112  
73  
54  
39  
25  
t2CYC  
Two cycle time (from rising edge to next rising edge or  
from falling edge to next falling edge of STROBE)  
230  
154  
115  
86  
57  
tDS  
Data setup time (at recipient)  
Data hold time (at recipient)  
15  
5
10  
5
7
5
7
5
5
5
tDH  
tDVS  
Data valid setup time at sender (time from data bus being  
valid until STROBE edge)  
70  
48  
30  
20  
6
tDVH  
Data valid hold time at sender (time from STROBE edge  
until data may go invalid)  
6
0
6
0
6
0
6
0
6
0
tFS  
tLI  
First STROBE (time for device to send first STROBE)  
230  
150  
200  
150  
170  
150  
130  
100  
120  
100  
Limited interlock time (time allowed between an action by  
one agent, either host or device, and the following action  
by the other agent)  
0
0
0
0
0
tMLI  
tUI  
Interlock time with minimum  
20  
0
20  
0
20  
0
20  
0
20  
0
Unlimited interlock time  
tAZ  
Maximum time allowed for outputs to release  
10  
10  
10  
10  
10  
tZAH  
tZAD  
tENV  
20  
0
20  
0
20  
0
20  
0
20  
0
Minimum delay time required for output drivers turning on  
(from released state)  
Envelope time (all control signal transitions are within the  
DMACK envelope by this much time)  
20  
70  
50  
75  
20  
70  
30  
70  
20  
70  
20  
60  
20  
55  
NA  
60  
20  
55  
NA  
60  
tSR  
tRFS  
tRP  
STROBE to DMARDY (response time to ensure the  
synchronous pause case when the recipient is pausing)  
Ready-to-final-STROBE time (no more STROBE edges may  
be sent this long after receiving DMARDY- negation)  
Ready-to-pause time (time until a recipient may assume  
that the sender has paused after negation of DMARDY-)  
160  
125  
100  
100  
100  
tIORDYZ Pull-up time before allowing IORDY to be released  
tZIORDY Minimum time device shall wait before driving IORDY  
20  
20  
20  
20  
20  
0
0
0
0
0
tACK  
Setup and hold times before assertion and negation of  
DMACK-  
20  
20  
20  
20  
20  
tSS  
Time from STROBE edge to STOP assertion when the  
sender is stopping  
50  
50  
50  
50  
50  
DMARQ  
(device)  
tUI  
DMACK-  
(host)  
tFS  
tACK  
tENV  
tZAD  
STOP  
(host)  
tFS  
tACK  
tENV  
HDMARDY-  
(host)  
tZAD  
tZIORDY  
DSTROBE  
(device)  
tAZ  
tVDS  
tDVH  
DD(15:0)  
tACK  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 4  
Initiating an Ultra DMA Data In Burst  
5 – 5  
AT INTERFACEDESCRIPTION  
t2CYC  
tCYC  
tCYC  
t2CYC  
DSTROBE  
at device  
tDVH  
tDVH  
tDVH  
tDVS  
tDVS  
DD(15:0)  
at device  
DSTROBE  
at host  
tDH  
tDS  
tDH  
tDS  
tDH  
DD(15:0)  
at host  
Figure 5 - 5  
Sustained Ultra DMA Data In Burst  
DMARQ  
(device)  
DMACK-  
(host)  
tRP  
STOP  
(host)  
tSR  
HDMARDY-  
(host)  
tRFS  
DSTROBE  
(device)  
DD(15:0)  
(device)  
Figure 5 - 6  
Host Pausing an Ultra DMA Data In Burst  
5 – 6  
AT INTERFACEDESCRIPTION  
DMARQ  
(device)  
tMLI  
DMACK-  
(host)  
tACK  
tLI  
tLI  
STOP  
(host)  
tACK  
tLI  
HDMARDY-  
(host)  
tSS  
tIORDYZ  
DSTROBE  
(device)  
tZAH  
tAZ  
tDVS  
tDVH  
DD(15:0)  
CRC  
tACK  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 7  
Device Terminating an Ultra DMA Data In Burst  
DMARQ  
(device)  
tLI  
tMLI  
DMACK-  
(host)  
tZAH  
tAZ  
tRP  
tACK  
STOP  
(host)  
tACK  
HDMARDY-  
(host)  
tRFS  
tMLI  
tLI  
tIORDYZ  
DSTROBE  
(device)  
tDVS  
tDVH  
DD(15:0)  
CRC  
tACK  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 8  
Host Terminating an Ultra DMA Data In Burst  
5 – 7  
AT INTERFACEDESCRIPTION  
DMARQ  
(device)  
tUI  
DMACK-  
(host)  
tACK  
tENV  
STOP  
(host)  
tZIORDY  
tLI  
tUI  
DDMARDY-  
(device)  
tACK  
HSTROBE  
(host)  
tDVS  
tDVH  
DD(15:0)  
(host)  
tACK  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 9  
Initiating an Ultra DMA Data Out Burst  
t2CYC  
tCYC  
tCYC  
t2CYC  
HSTROBE  
at host  
tDVH  
tDVH  
tDVH  
tDVS  
tDVS  
DD(15:0)  
at host  
HSTROBE  
at device  
tDH  
tDS  
tDH  
tDS  
tDH  
DD(15:0)  
at device  
Figure 5 - 10  
Sustained Ultra DMA Data Out Burst  
5 – 8  
AT INTERFACEDESCRIPTION  
tRP  
DMARQ  
(device)  
DMACK-  
(host)  
STOP  
(host)  
tSR  
DDMARDY-  
(device)  
tRFS  
HSTROBE  
(host)  
DD(15:0)  
(host)  
Figure 5 - 11  
Device Pausing an Ultra DMA Data Out Burst  
tLI  
DMARQ  
(device)  
tMLI  
DMACK-  
(host)  
tLI  
tACK  
tSS  
STOP  
(host)  
tLI  
tIORDYZ  
DDMARDY-  
(device)  
tACK  
HSTROBE  
(host)  
tDVS  
tDVH  
DD(15:0)  
(host)  
CRC  
tACK  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 12  
Host Terminating an Ultra DMA Data Out Burst  
5 – 9  
AT INTERFACEDESCRIPTION  
DMARQ  
(device)  
DMACK-  
(host)  
tLI  
tMLI  
tACK  
STOP  
(host)  
tRP  
tIORDYZ  
DDMARDY-  
(device)  
tRFS  
tMLI  
tACK  
tDVH  
tACK  
tLI  
HSTROBE  
(host)  
tDVS  
DD(15:0)  
(host)  
CRC  
DA0, DA1, DA2,  
CS0-, CS1-  
Figure 5 - 13  
Device Terminating an Ultra DMA Data Out Burst  
5 – 10  
SECTION 6  
Ho s t S o ft w a re In t e rfa c e  
The host communicates with the drive through a set of controller registers accessed via the host’s I/ O ports.  
These registers divide into two groups: the Task File, used for passing commands and command parameters and  
the Control/ Diagnostic registers.  
Ta s k File Re g is t e rs  
The Task File consists of eight registers used to control fixed disk operations. The host accesses each register  
by the I/ O port address shown in this Task File register map:  
I/O PORT  
1F0h  
1F1h  
1F2h  
1F3h  
1F4h  
1F5h  
1F6h  
1F7h  
READ  
WRITE  
Data Register  
Error Register  
Sector Count  
Sector Number  
Cylinder Low  
Cylinder High  
Drive/Head (SDH)  
Status Register  
Data Register  
Features Register  
Sector Count  
Sector Number  
Cylinder Low  
Cylinder High  
Drive/Head (SDH)  
Command Register  
Da t a Re g is t e r  
Provides access to the drive’s sector buffer for read and write operations. With the exception of ECC byte  
transfers (which, during Read long and Write long commands, are 8 bits wide), data transfers through the  
Data register are all 16 bits wide.  
Erro r Re g is t e r  
A read-only register containing specific information regarding the previous command. Data interpretation  
differs depending on whether the controller is in operational or diagnostic mode. A power up, reset,  
software reset, or receipt of a diagnostic command sets the controller into diagnostic mode. This mode  
invalidates contents of the Status register. The contents of the Error register reflect a completion code.  
Issuing any command (apart from a Diagnostic command) places the controller into operational mode.  
In operational mode, the Error register is valid only when the Error bit in the Status register is set. The bit  
definitions for operational mode follow:  
7
0
6
5
0
4
3
0
2
1
0
ECC  
IDNF  
ABRT  
TK0  
AMNF  
Interface  
CRC  
Data  
ECC Error  
Not  
Used  
ID  
Not  
Used  
Aborted  
Command  
Track 0  
Error  
Address  
Mark Not  
Found  
Not Found  
Interface CRC – An interface CRC error occurred during an Ultra DMA transfer.  
Data ECC Error – An non-correctable ECC error occurred during a Read Sector command.  
Firm w are Problem – Indicates a firmware problem was detected, (e.g., invalid interrupt, divide overflow).  
ID Not Found – Either a matching ID field not found, or a CRC error occurred.  
Aborted Com m and – Invalid commands, write fault, no seek complete, or drive not ready.  
Track 0 Error – Track 0 was not found during execution of a Restore command.  
Address Mark Not Found – The Address Mark could not be found after an ID match.  
Fe a t u re s Re g is t e r  
Enables or disables features through the Set Features command.  
6 – 1  
HOST SOFTWAREINTERFACE  
S e c t o r Co u n t Re g is t e r  
Holds the number of sectors to be sent during a Read or Write command, and the number of sectors per  
track during a Format command. A value of zero in this register implies a transfer of 256 sectors. A multi-  
sector operation decrements the Sector Count register. If an error occurs during such an operation, this  
register contains the remaining number of sectors to be transferred.  
S e c t o r Nu m b e r Re g is t e r  
Holds the starting sector number for any disk operation. The register is updated as each sector is processed in  
a multi-sector operation.  
Cylin d e r Nu m b e r Re g is t e rs  
Two 8-bit Cylinder Number registers (Low and High) specify the starting cylinder for disk operation.  
De vic e /He a d Re g is t e r  
Used to specify the drive and head number to be operated on during any disk operations. Within the  
context of a Set Parameters command, this register specifies the maximum number of heads on the drive.  
Bit definitions follow:  
7
1
6
5
1
4
3
2
1
0
LBA  
DRV  
HS3  
HS2  
HS1  
HS0  
Drive  
Head  
Select  
Head  
Select  
Head  
Select  
Mode  
Select  
Select  
Select LBA Mode – Enabling this bit for commands not supported by LBA mode will abort the selected command. When set,  
the Task File register contents are defined as follows for the Read/Write and translate command:  
CONTENTS  
Sector Number  
Cylinder Low  
Cylinder High  
Drive/Head  
LBA BITS  
0 - 7  
8 - 15  
16 - 23  
24 - 27  
Drive Select – Set to 0 to select the master drive; set to 1 to select the slave drive.  
Head Select – Specifies the binary coded address of the head to be selected.  
S t a t u s Re g is t e r  
Contains results of the last command executed, and the drive’s status. The other seven Task File registers may  
be read only when bit 7 (BUSY) of the Status register is low. Reading any of the Task File registers when  
BUSY is high returns the value of the Status register. Reading the Status register also clears any interrupt  
request to the host. Bit definitions follow:  
7
6
5
4
3
2
0
1
0
0
BUSY  
DRDY  
DF  
DSC  
DRQ  
ERR  
Error  
Controller  
Busy  
Device  
Ready  
Device  
Fault  
Device Seek Data  
Complete Request  
Controller Busy – Goes active when a command is written to the Command register, indicating controller task  
execution. After a command, this bit resets.  
Device Ready – Indicates that the drive is ready for commands. If drive ready is not present, all commands abort.  
Device Fault – Indicates the drives detection of a write fault condition, causing all commands to abort.  
Device Seek Com plete – Signifies a seek completion, and that the drive is on track.  
Data Request – Indicates that the drives sector buffer is ready for data transfer.  
Error – The Error bit sets when the previous command has completed with a non-recoverable error.  
6 – 2  
HOST SOFTWAREINTERFACE  
Co m m a n d Re g is t e r  
Contains code for the command to be performed. Additional command information should be written to the  
task file before the Command register is loaded. When this register is written, the BUSY bit in the Status  
register sets, and interrupt request to the host clears; invalid commands abort. (Detailed information on interface  
commands is given in Section 7.) Hex values for valid command formats follow:  
Re a d Co m m a n d s  
Read Sector(s)  
20h  
21h  
22h  
23h  
40h  
41h  
E4h  
C4h  
C8h  
C9h  
Normal reads; retries enabled  
Normal reads; retries disabled  
Read Long; retries enabled  
Read Long; retries disabled  
Retries enabled  
Read Verify Sector(s)  
Retries disabled  
Read Sector Buffer  
Read Multiple  
Read DMA  
No retries  
Writ e Co m m a n d s  
Write Sector(s)  
30h  
31h  
32h  
33h  
3Ch  
E8h  
C5h  
CAh  
CBh  
Normal writes; retries enabled  
Normal writes; retries disabled  
Write Long; retries enabled  
Write Long; retries disabled  
Write Verify Sector(s)  
Write Sector Buffer  
Write Multiple  
Write DMA  
No retries  
Mo d e S e t /Ch e c k Co m m a n d s  
Set Features  
Set Multiple Mode  
EFh  
C6h  
P o w e r Mo d e Co m m a n d s  
Standby Immediate  
Idle Immediate  
Standby  
94/E0h Stops drive spindle; do not change time-out value  
95/E1h Starts spindle; do not change time-out value  
96/E2h Stops spindle; change time-out value  
97/E3h Starts spindle; change time-out value  
98/E5h  
Idle  
Check Power Mode  
Set Sleep Mode  
99/E6h  
In it ia liza t io n Co m m a n d s  
Identify Drive  
Initialize Drive Parameters  
Re-calibrate  
ECh  
91h  
1xh  
S e e k , Fo rm a t , a n d Dia g n o s t ic Co m m a n d s  
Seek  
7xh  
50h  
90h  
Format Track  
Execute Drive Diagnostic  
S .M.A.R.T. Co m m a n d s  
Execute S.M.A.R.T.  
B0h  
6 – 3  
HOST SOFTWAREINTERFACE  
S u m m a ry  
COMMAND NAME  
COMMAND CODE  
PARAMETERS USED  
b7  
0
0
1
0
1
0
0
0
0
1
1
1
1
1
1
1
1
1
b6  
0
0
1
0
1
0
1
1
1
0
0
1
1
1
1
1
1
1
b5  
0
1
0
1
0
1
0
0
1
0
0
1
1
1
1
0
0
0
b4  
1
0
0
1
0
1
0
1
1
1
1
0
0
0
0
0
0
0
b3  
x
b2  
x
b1  
x
b0  
x
F
SC  
N
Y
SN  
N
Y
C
N
Y
Y
Y
Y
Y
Y
Y
Y
N
N
N
N
N
N
Y
Y
N
SDH  
D
Y
Recalibrate  
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Y
Read Sector(s)  
Read DMA  
0
1
0
1
1
0
0
x
0
0
0
0
1
0
0
x
L
0
L
1
0
0
0
x
x
x
Y
Y
Y
Write Sector(s)  
Write DMA  
x
Y
Y
Y
x
Y
Y
Y
Write Verify Sector(s)  
Read Verify Sector(s)  
Format Track  
0
x
Y
Y
Y
Y
Y
Y
0
x
N
N
N
Y
N
Y
Y
Seek  
Y
Execute Diagnostic  
Initialize Parameters  
Read Sector Buffer  
Write Sector Buffer  
Identify Drive  
0
0
0
1
1
1
0
0
0
0
0
1
0
1
1
1
1
1
0
0
0
0
0
1
0
0
1
0
1
0
0
0
1
0
1
0
N
N
N
N
N
N
Y
D
Y
N
N
N
N
Y
D
D
D
D
Y
Set Features  
Read Multiple  
Write Multiple  
Set Multiple Mode  
N
N
N
Y
Y
Y
Y
N
D
TIMER VALUE  
TIME-OUT PERIOD  
Time-out disabled  
(value * 5) seconds  
((value - 240) * 30) minutes  
21 minutes  
0
1 - 240  
241 - 251  
252  
253  
254  
Vendor unique period = 10 hours  
Reserved  
255  
21 minutes, 15 seconds  
6 – 4  
HOST SOFTWAREINTERFACE  
Co n t ro l Dia g n o s t ic Re g is t e rs  
These I/ O port addresses reference three Control/ Diagnostic registers:  
I/ O PORT  
3F6h  
READ  
WRITE  
Fixed Disk Control  
Not used  
Alternate Status  
Digital Input  
3F7h  
Alt e rn a t e S t a t u s Re g is t e r  
Contains the same information as the Status register in the Task File. However, this register may be read at  
any time without clearing a pending interrupt.  
De vic e Co n t ro l Re g is t e r  
Contains the software Reset and Enable bit to enable interrupt requests to the host. Bit definitions follow:  
7
0
6
0
5
0
4
0
3
0
2
1
0
0
SRST  
Reset  
IEN  
IRQ Enable  
Reset – Setting the software Reset bit holds the drive in the reset state. Clearing the bit re-enables the drive.  
The software Reset bit must be held active for a minimum of 5 µsec.  
IRQ Enable – Setting the Interrupt Request Enable to 0 enables the IRQ 14 signal to the host. When this bit is set  
to 1, IRQ14 is tri-stated, and interrupts to the host are disabled. Any pending interrupt occurs when the bit is set to 0.  
The default state of this bit after power up is 0 (interrupt enabled).  
Dig it a l In p u t Re g is t e r  
Contains information about the state of the drive. Bit definitions follow:  
7
x
6
5
4
3
2
1
0
-WG  
-HS3  
-HS2  
-HS1  
-HS0  
-DS1  
DS0  
Reserved  
Head  
Select 3  
Head  
Select 2  
Head  
Select 1  
Head  
Select 0  
Drive  
Select 1  
Drive  
Select 0  
Gate  
Bit 7 of the host data bus is not driven when this register is read.  
-Write Gate – Reflects the state of the active low write gate signal on the drive.  
-Head Select 3 through -Head Select 0 – Represents the ones complement of the currently selected head number.  
-Drive Select 1 – Is 0 if drive 1 selected; 1 otherwise.  
-Drive Select 0 – Is 0 if drive 0 selected; 1 otherwise.  
6 – 5  
HOST SOFTWAREINTERFACE  
Re s e t a n d In t e rru p t Ha n d lin g  
Re s e t Ha n d lin g  
One of three different conditions may cause a reset: power on, hardware reset or software reset. All three  
cause the interface processor to initialize itself and the Task File registers of the interface. A reset also causes a  
set of the Busy bit in the Status register. The Busy bit does not clear until the reset clears and the drive  
completes initialization. Completion of a reset operation does not generate a host interrupt.  
Task File registers are initialized as follows:  
Error  
1
1
1
0
0
0
Sector Count  
Sector Number  
Cylinder Low  
Cylinder High  
Drive/Head  
In t e rru p t Ha n d lin g  
The drive requests data transfers to and from the host by asserting its IRQ 14 signal. This signal interrupts the  
host if enabled by bit 1 (IRQ enable) of the Fixed Disk Control register.  
Clear this interrupt by reading the Status register, writing the Command register, or by executing a host  
hardware or software reset.  
6 – 6  
SECTION 7  
In t e rfa c e Co m m a n d s  
The following section describes the commands (and any parameters necessary to execute them),  
as well as Status and Error register bits affected.  
Re a d Co m m a n d s  
Read Sector(s)  
Read Verify Sector(s)  
Read Sector Buffer  
Read DMA  
Multi-word DMA  
Ultra DMA  
Read Multiple  
Set Multiple  
Writ e Co m m a n d s  
Write Sector(s)  
Write Verify Sector(s)  
Write Sector Buffer  
Write DMA  
Multi-word DMA  
Ultra DMA  
Write Multiple  
S e t Fe a t u re Co m m a n d s  
Set Features Mode  
P o w e r Mo d e Co m m a n d s  
Standby Immediate  
Idle Immediate  
Standby  
Idle  
Check Power Mode  
Set Sleep Mode  
Default Power-on Condition  
In it ia liza t io n Co m m a n d s  
Identify Drive  
Initialize Drive Parameters  
7 – 1  
INTERFACECOMMANDS  
Re a d Co m m a n d s  
Re a d S e c t o r(s )  
Reads from 1 to 256 sectors, as specified in the Command Block, beginning at the specified sector. (A sector  
count of 0 requests 256 sectors.) Immediately after the Command register is written, the drive sets the BSY  
bit and begins execution of the command. If the drive is not already on the desired track, an implied seek is  
performed.  
Once at the desired track, the drive searches for the data address mark of the requested sector. The data  
address mark must be recognized within a specified number of bytes, or the Data Address Mark Not Found  
error will be reported. Assuming the data address mark is found:  
1.  
2.  
3.  
4.  
The data field is read into the sector buffer.  
Error bits are set (if an error was encountered).  
The DRQ bit is set.  
An interrupt is generated.  
The DRQ bit is always set, regardless of the presence or absence of an error condition after the sector.  
Upon command completion, the Command Block registers contain the numbers of the cylinder, head and  
sector of the last sector read. Back-to-back sector read commands set DRQ and generate an interrupt when  
the sector buffer is filled at the completion of each sector. The drive is then ready for the data to be read by  
the host. DRQ is reset and BSY is set immediately when the host empties the sector buffer.  
If an error occurs during Read Sector commands, the read terminates at the sector where the error occurred.  
The host may then read the Command Block to determine the nature of that error, and the sector where it  
happened. If the error type is a correctable or an non-correctable data error, the flawed data is loaded into  
the sector buffer.  
A Read Long command sets the Long bit in the command code and returns the data and the ECC bytes in  
the data field of the specified sector. During a Read Long, the drive does not check the ECC bytes to  
determine if there has been a data error. The Read Long command is limited to single sector requests.  
Re a d Ve rify S e c t o r(s )  
Identical to the Read Sector(s) command, except that:  
1.  
2.  
3.  
DRQ is never set,  
No data is transferred back to the host and  
The long bit is not valid.  
7 – 2  
INTERFACECOMMANDS  
Re a d DMA  
Multi-word DMA  
Identical to the Read Sector(s) command, except that  
1.  
2.  
The host initializes a slave-DMA channel prior to issuing the command,  
Data transfers are qualified by DMARQ and are performed by the slave-DMA channel  
and  
3.  
The drive issues only one interrupt per command to indicate that data transfer has  
terminated and status is available.  
Ultra DMA  
With the Ultra DMA Read protocol, the control signal (DSTROBE) that latches data from DD(15:0) is  
generated by the devices which drives the data onto the bus. Ownership of DD(15:0) and this data strobe  
signal are given DSTROBE to the drive during an Ultra DMA data in burst.  
During an Ultra DMA Read burst, the drive always moves data onto the bus, and, after a sufficient time to  
allow for propagation delay, cable settling, and setup time, the sender shall generate a DSTROBE edge to  
latch the data. Both edges of DSTROBE are used for data transfers.  
Any unrecoverable error encountered during execution of a Read DMA command terminates data transfer  
after the transfer of all sectors prior to the sector where the error was detected. The sector in error is not  
transferred. The drive generates an interrupt to indicate that data transfer has terminated and status is  
available. The error posting is identical to the Read Sector(s) command.  
Re a d Mu lt ip le  
Performs similarly to the Read Sector(s) command, except that for each READ MULTIPLE command data  
transfers are multiple sector blocks and the Long bit is not valid.  
Execution is also similar to that of the READ SECTOR(S) command, except that:  
1.  
2.  
Several sectors are transferred to the host as a block, without intervening interrupts.  
DRQ qualification of the transfer is required only at the start of each block, not of each sector.  
The block count consists of the number of sectors to be transferred as a block. (The block count is  
programmed by the Set Multiple Mode command, which must be executed prior to the Read Multiple  
command.) READ LONG command is limited to single sector requests.  
When the Read Multiple command is issued, the Sector Count register contains the number of sectors  
requested — not the number of blocks or the block count. If the number of sectors is not evenly divisible  
by the block count, as many full blocks as possible are transferred, followed by a final, partial block transfer.  
This final, partial block transfer is for N sectors, where N = (sector count) modulo (block count)  
The Read Multiple operation will be rejected with an Aborted Command error if attempted:  
1.  
2.  
Before the Set Multiple Mode command has been executed, or  
When Read Multiple commands are disabled.  
The controller reports disk errors encountered during Read Multiple commands at the start of the block or  
partial block transfer. However, DRQ still sets, and the transfer occurs normally, along with the transfer of  
any corrupt data. Remaining block data from the following the sector in error is not valid.  
If the Sector Count register contains 0 when the Set Multiple Mode command is issued, Read Multiple and  
Write Multiple commands are disabled; no error is returned. Once the appropriate action has been taken, the  
controller resets BSY and generates an interrupt. At power up, or after a hardware or software reset, Read  
Multiple and Write Multiple commands are disabled by default.  
7 – 3  
INTERFACECOMMANDS  
S e t Mu lt ip le Mo d e  
Enables the controller to perform Read and Write Multiple operations, and establishes the block count for  
these commands. Before issuing this command, the Sector Count register should be loaded with the number  
of sectors per block. The drives support block sizes of 2, 4, 8 and 16 sectors.  
When this command is received, the controller sets BSY and examines the Sector Count register contents. If  
they contain a valid and supported block count value, that value is loaded for all subsequent Read and Write  
Multiple commands, and execution of those commands is enabled. An invalid and unsupported block count  
in the register results in an Aborted Command error and disallows Read Multiple and Write Multiple  
commands.  
Writ e Co m m a n d s  
Writ e S e c t o r(s )  
Writes from 1 to 256 sectors, beginning at a sector specified in the Command Block. (A sector count of 0  
requests 256 sectors.)  
When the Command register is written, the drive sets the DRQ bit and waits for the host to fill the sector  
buffer with the data to be written. An interrupt is not generated to start the first buffer fill operation.  
Once the buffer is full, the drive resets DRQ, sets BSY, and begins command execution. If the drive is not  
already on the desired track, an implied seek is performed.  
The data loaded in the buffer is written to the data field of the sector, followed by the ECC bytes. Upon  
command completion, the Command Block registers contain the cylinder, head and sector number of the  
last sector written. The next time the buffer is ready to be filled during back-to-back Write Sector  
commands, DRQ is set and an interrupt is generated.  
After the host fills the buffer, DRQ is reset and BSY is set. If an error occurs, Write Sector operations  
terminate at the sector containing the error.  
The Command Block registers then contain the numbers of the cylinder, head and sector where the error  
occurred. The host may read the Command Block to determine the nature of that error, and on which  
sector it happened. A Write Long may be executed by setting the Long bit in the command code. The  
Write Long command writes the data and the ECC bytes directly from the sector buffer; the drive itself does  
not generate the ECC bytes. Restrict Write Long commands to PIO Mode 0.  
Writ e Ve rify S e c t o r(s )  
Identical to the Write Sector(s) command, except that the requested sectors are verified immediately after  
being written. The verify operation reads (without transferring), and checks for data errors. Any errors  
encountered during this operation are reported.  
Writ e S e c t o r Bu ffe r  
Allows the host to overwrite the contents of the drive’s sector buffer with a selected data pattern. When this  
command is received, the drive:  
1. Sets BSY,  
2. Sets up the sector buffer for a write operation,  
3. Sets DRQ,  
4. Resets BSY and  
5. Generates an interrupt.  
The host may then write up to 256 words of data to the buffer. A disk write task begins to store the host  
data to disk. Host write commands continue to be accepted and data transferred to the buffer until either  
the write command stack is full or the data buffer is full. The drive may reorder write commands to optimize  
drive throughput.  
7 – 4  
INTERFACECOMMANDS  
Writ e Mu lt ip le  
Performs similarly to the Write Sector(s) command, except that:  
1. The controller sets BSY immediately upon receipt of the command,  
2. Data transfers are multiple sector blocks and  
3. The Long bit and Retry bit is not valid.  
Command execution differs from Write Sector(s) because:  
1. Several sectors transfer to the host as a block without intervening interrupts.  
2. DRQ qualification of the transfer is required at the start of the block, not on each sector.  
The block count consists of the number of sectors to be transferred as a block and is programmed by the Set  
Multiple Mode command, which must be executed prior to the Write Multiple command. When the Write  
Multiple command is issued, the Sector Count register contains the number of sectors requested — not the  
number of blocks or the block count.  
If the number of sectors is not evenly divisible by the block count, as many full blocks as possible are  
transferred, followed by a final, partial block transfer. This final, partial block transfer is for N sectors, where  
N = (sector count) modulo (block count)  
The Write Multiple operation will be rejected with an Aborted Command error if attempted:  
1. Before the Set Multiple Mode command has been executed, or  
2. When Write Multiple commands are disabled.  
All disk errors encountered during Write Multiple commands report after the attempted disk write of the  
block or partial block in which the error occurred.  
The write operation ends with the sector in error, even if it was in the middle of a block. When an error  
occurs, subsequent blocks are not transferred. When DRQ is set at the beginning of each full and partial  
block, interrupts are generated.  
Writ e DMA  
Multi-word DMA  
Identical to the Write Sector(s) command, except that:  
1.  
2.  
3.  
The host initializes a slave-DMA channel prior to issuing the command,  
Data transfers are qualified by DMARQ and are performed by the slave-DMA channel and  
The drive issues only one interrupt per command to indicate that data transfer has terminated  
at status is available.  
Ultra DMA  
With the Ultra DMA Write protocol, the control signal (HSTROBE) that latches data from DD(15:0) is  
generated by the devices which drives the data onto the bus. Ownership of DD(15:0) and this data  
strobe signal are given to the host for an Ultra DMA data out burst.  
During an Ultra DMA Write burst, the host always moves data onto the bus, and, after a sufficient time to  
allow for propagation delay, cable settling, and setup time, the sender shall generate a HSTROBE edge to  
latch the data. Both edges of HSTROBE are used for data transfers.  
Any error encountered during Write DMA execution results in the termination of data transfer. The drive  
issues an interrupt to indicate that data transfer has terminated and status is available in the error register.  
The error posting is the same as that of the Write Sector(s) command.  
7 – 5  
INTERFACECOMMANDS  
S e t Fe a t u re Co m m a n d s  
S e t Fe a t u re s Mo d e  
Enables or disables features supported by the drive. When the drive receives this command it:  
1. Sets BSY,  
2. Checks the contents of the Features register,  
3. Clears BSY and  
4. Generates an interrupt.  
If the value of the register is not a feature supported by the drive, the command is aborted.  
The acceptable values in the Features register are defined as follows:  
VALUE  
02h*  
03h  
DESCRIPTION  
Enabled write cache  
Set transfer mode based on value in Sector Count register  
44h  
Length of data appended on Read Long/Write Long commands specified in the  
Identify Device information  
55h  
Disable read look-ahead feature  
66h*  
82h  
Disable reverting to power-on defaults  
Disable write cache  
AAh*  
BBh*  
CCh  
Enable read look-ahead feature  
4 bytes of Maxtor specific data appended on Read Long/Write Long commands  
Enable reverting to power-on defaults  
* Enabled at power up by default.  
7 – 6  
INTERFACECOMMANDS  
P o w e r Mo d e Co m m a n d s  
S t a n d b y Im m e d ia t e – 9 4 h /E0 h  
Spin down and do not change time out value. This command will spin the drive down and cause the drive  
to enter the STANDBY MODE immediately. If the drive is already spun down, the spin down sequence is  
not executed.  
Id le Im m e d ia t e – 9 5 h /E1 h  
Spin up and do not change time out value. This command will spin up the spin motor if the drive is spun  
down, and cause the drive to enter the IDLE MODE immediately. If the drive is already spinning, the spin  
up sequence is not executed. The actuator is parked and some circuits are powered off.  
S t a n d b y – 9 6 h /E2 h  
Spin down and change time out value. This command will spin the drive down and cause the drive to enter  
the STANDBY MODE immediately. If the drive is already spun down, the spin down sequence is not  
executed. A non-zero value placed in the sector count register will enable the Automatic Power Down  
sequence. The timer will begin counting down when the drive returns to the IDLE MODE. A value of zero  
placed in the sector count register will disable the Automatic Power Down sequence.  
Id le – 9 7 h /E3 h  
Spin up and change time out value. This command will spin-up the spin motor if the drive is spun-down.  
If the drive is already spinning, the spin up sequence is not executed. A non-zero value placed in the Sector  
Count register will enable the Automatic Power Down sequence and their timer will begin counting down  
immediately. A value of zero placed in the Sector Count register will disable the Automatic Power Down  
sequence. The actuator is parked and some circuits are powered off.  
Ch e c k P o w e r Mo d e – 9 8 h /E5 h  
This command returns a code in the Sector Count register that determines the current Power Mode status of  
the drive. If the drive is in, going to, or recovering from the STANDBY MODE the drive sets the Sector  
Count register to OOh. If the drive is in the IDLE MODE or ACTIVE MODE, the drive sets the Sector  
Count register to FFh.  
S e t S le e p Mo d e – 9 9 h /E6 h  
This command will spin the drive down and cause the drive to enter the SLEEP MODE immediately. If the  
drive is already spun down, the spin down sequence is not executed.  
Note: The only way to recover from SLEEP MODE is with a software reset or a hardware reset.  
De fa u lt P o w e r-o n Co n d it io n  
The drive’s default power on condition is the ACTIVE MODE.  
Upon receiving a Power Mode command, except the SLEEP MODE command, the drive sets BSY and  
performs the requested power operation. Once the requested Power Mode change has begun, the drive  
resets BSY and generates an interrupt - without waiting for the drive to spin up or spin down. Upon  
receiving a SLEEP MODE command the drive is spun down, and when it is stopped, the drive resets BSY  
and generates an interrupt.  
7 – 7  
INTERFACECOMMANDS  
When enabling the Automatic Power Down sequence, the value placed in the Sector Count register is  
multiplied by five seconds to obtain the Time-out Interval value. If no drive commands are received from  
the host within the Time-out Interval, the drive automatically enters the STANDBY mode. The minimum  
value is 5 seconds.  
TIMER VALUE  
TIME-OUT PERIOD  
Time-out disabled  
(value * 5) seconds  
((value - 240) * 30) minutes  
21 minutes  
0
1 - 240  
241 - 251  
252  
253  
Vendor unique period = 10  
hours  
254  
255  
Reserved  
21 minutes, 15 seconds  
While the drive is in STANDBY MODE, any commands received from the host are accepted and executed  
as they would in normal operation, except that the spin motor is started if required to execute a disk  
command. Under these conditions, the drive will set BSY when command processing would normally begin  
and will leave BSY set until the drive comes up to speed and the disk command can be executed. Disk  
commands issued while the drive is in STANDBY MODE, restarts the Time-out Interval after completing  
the command. A reset must be issued before attempting to issue any commands while the drive in  
SLEEP MODE.  
7 – 8  
INTERFACECOMMANDS  
In it ia liza t io n Co m m a n d s  
Id e n t ify Drive  
Allows the host to receive parameter information from the drive.  
When the command is received, the drive:  
1. Sets BSY,  
2. Stores the required parameter information in the sector buffer,  
3. Sets the DRQ bit and  
4. Generates an interrupt.  
The host may then read the information out of the sector buffer. Parameter words in the buffer follow.  
Note that all reserved bits or words should be zeroes.  
WORD CONTENT DESCRIPTION  
0
General configuration  
15 = device (0 = ATA device, 1 = ATAPI)  
14-8 = retired  
7, 1 = removable media device  
6, 1 = not removable controller and/or device  
5-3 = retired  
2 = response incomplete  
1 = retired  
0 = reserved  
1
2
Number of logical cylinders  
Reserved  
3
4-5  
6
7-8  
9
Number of logical heads  
Retired  
Number of logical sectors per logical track  
Reserved  
Retired  
10 - 19 Drive serial number (20 ASCII characters)  
20  
21  
22  
Not used  
Buffer size in 512 byte increments (0000h = not specified)  
Number of Maxtor specific bytes available on Read/Write Long commands  
23 - 26 Firmware revision (8 ASCII characters)  
27 - 46 Model number (40 ASCII characters)  
47  
48  
49  
Maximum number of sectors that can be transferred per interrupt on read and write multiple commands  
Reserved  
Capabilities  
15 - 14 = reserved  
13 = standby timer (1 = values as specified in this standard are supported, 0 = values are Maxtor specific)  
12 = reserved (advanced PIO mode support)  
11, 1 = IORDY supported, 0 = IORDY may be supported  
10, 1 = IORDY can be disabled  
9-8 = reserved  
7-0 = not used  
7 – 9  
INTERFACECOMMANDS  
WORD CONTENT DESCRIPTION  
50 Reserved  
51 15-8 = PIO data transfer mode  
7-0 = not used  
52  
53  
15-8 = DMA data transfer mode  
7-0 = not used  
15 = reserved  
2, 1 = the fields supported in words 88 are valid, 0 = the fields supported in words 88 are not valid  
1, 1 = the fields reports in words 64-70 are valid, 0 = the fields reports in words 64-70 are not valid  
0, 1 = the fields reports in words 54-58 are valid, 0 = the fields reports in words 54-58 are not valid  
Number of current logical cylinders  
Number of current logical heads  
54  
55  
56  
Number of logical sectors per track  
57 - 58 Current capacity in sectors  
59  
15-9 = reserved  
8, 1 = multiple sector setting is valid  
7-0xxh = current setting for number of sectors that can per transferred per interrupt on Read/Write Multiple  
command  
60 - 61 Total number of user addressable sectors (LBA mode only)  
62  
63  
Reserved  
15-8 = Multi-word DMA transfer mode active  
7-0 = Multi=word DMA transfer modes supported  
64  
15-8 = reserved  
7-0 = advanced PIO transfer modes supported  
65  
66  
67  
68  
Minimum multi-word DMA transfer cycle time (15-0 = cycle time in nanoseconds)  
Manufacturer's recommeded multi-word DMA transfer cycle time (15-0 = cycle time in nanoseconds)  
Minimum PIO transfer cycle time without flow control (15-0 = cycle time in nanoseconds)  
Minimum PIO transfer cycle time with IORDY flow control (15-0 = cycle time in nanoseconds)  
69-79 Reserved  
80  
15-6 = reserved  
5, 1 = supports ATA/ATAPI-5  
4, 1 = supports ATA/ATAPI-4  
3, 1 = supports ATA-3  
2, 1 = supports ATA-2  
1, 1 = supports ATA-1  
0, reserved  
81  
82  
Minor version number  
Command set supported. If words 82 and 83 = 0000h or FFFFh command set notification not supported.  
15, 1 = supports the Identify Device DMA command  
14, 1 = supports the NOP command  
13, 1 = supports the Write Buffer command  
12, 1 = supports the Read Buffer command  
11, 1 = supports the Read Buffer command  
10, 1 = supports Host-Protected Area feature set  
9, 1 = supports the Device Reset command  
8, 1 = supports Service Interupt  
7, 1 = supports Release Interupt  
6, 1 = supports Look Ahead  
5, 1 = supports Write Cache  
4, 1 = supports the Packet command feature set  
3, 1 = supports the Power Management feature command  
2, 1 = supports the Removable feature command  
1, 1 = supports the Security featurecommand  
0, 1 = supports the SMART feature set  
7 – 10  
INTERFACECOMMANDS  
WORD CONTENT DESCRIPTION  
83  
Command sets supported. If words 82, 83 and 84 = 0000h or FFFFh command set notification not  
supported.  
15 = shall be cleared to zero  
14 = shall be set to one  
13-1 = reserved  
0, 1 = supports Download Microcode command  
84  
85  
Command set extensions supported. If words 84, 85 and 86 = 0000h or FFFFh command set  
notification not supported.  
15 = shall be cleared to zero  
14 = shall be set to one  
13-0 = reserved  
Command set enabled. If words 84, 85 and 86 = 0000h or FFFFh command set notification not  
supported.  
15, 1 = Identify Device DMA command enabled  
14, 1 = NOP command enabled  
13, 1 = Write Buffer command enabled  
12, 1 = Read Buffer command enabled  
11, 1 = Write Verify command enabled  
10, 1 = Host Protected Area feature set enabled  
9, 1 = Device Reset command enabled  
8, 1 = Service Interrupt enabled  
7, 1 = Release Interrupt enabled  
6, 1 = Look Ahead enabled  
5, 1 = Write Cache enabled  
4, 1 = Packet command feature set enabled  
3, 1 = Power Mangement feature set enabled  
2, 1 = Removable feature set enabled  
1, 1 = Security feature set enabled  
0, 1 = SMART feature set enabled  
Command sets enabled. If words 85, 86 and 87 = 0000h or FFFFh command set notification not  
supported.  
86  
15 = shall be cleared to zero  
14 = shall be set to one  
13-1 = reserved  
0, 1 = supports Download Microcode command  
Command sets enabled. If words 85, 86 and 87 = 0000h or FFFFh command set notification not  
supported.  
15 = shall be cleared to zero  
14 = shall be set to one  
13-0 = reserved  
Ultra DMA  
87  
88  
15-13 Reserved  
12 1 = Ultra DMA mode 4 is selected  
0 = Ultra DMA mode 4 is not selected  
11 1 = Ultra DMA mode 3 is selected  
0 = Ultra DMA mode 3 is not selected  
10 1 = Ultra DMA mode 2 is selected  
0 = Ultra DMA mode 2 is not selected  
9
1 = Ultra DMA mode 1 is selected  
0 = Ultra DMA mode 1 is not selected  
1 = Ultra DMA mode 0 is selected  
0 = Ultra DMA mode 0 is not selected  
8
7-5 Reserved  
4
3
2
1
0
1 = Ultra DMA mode 4 and below are supported  
1 = Ultra DMA mode 3 and below are supported  
1 = Ultra DMA mode 2 and below are supported  
1 = Ultra DMA mode 1 and below are supported  
1 = Ultra DMA mode 0 is supported  
127  
128  
Reserved  
Security Status  
15-9 Reserved  
8
Security Level 0 = High, 1 = Maximum  
7-5 Reserved  
4
3
2
1
0
1 = Security count expired  
1 = Security frozen  
1 = Security locked  
1 = Security enabled  
1 = Security supported  
129-130 Reserved  
131  
Spin at power-up, but 0 is asserted when no spin at power-up is enabled.  
132-159 Maxtor-specific (not used)  
160-255 Reserved  
7 – 11  
INTERFACECOMMANDS  
In it ia lize Drive P a ra m e t e rs  
Enables the drive to operate as any logical drive type. The drive will always be in the translate mode because  
of Zone Density Recording, which varies the number of sectors per track depending on the zone.  
Through setting the Sector Count Register and Drive Head Register, this command lets the host alter the  
drive's logical configuration. As a result, the drive can operate as any equal to or less than capacity drive type.  
Do not exceed the total number of sectors available on the drive:  
When this command is executed, the drive reads the Sector Counter Register and the Drive Head Register  
(and so determines the number of the logical sectors per track and maximum logical head number per  
cylinder and will calculate the number of logical cylinders.)  
Upon receipt of the command, the drive:  
1. Sets BSY,  
2. Saves the parameters,  
3. Resets BSY and  
4. Generates an interrupt.  
To specify maximum heads, write 1 less than the maximum (e.g. write 4 for a 5 head drive). To specify  
maximum sectors, specify the actual number of sectors (e.g. 17 for a maximum of 17 sectors/ track).  
The sector count and head values are not checked for validity by this command. If they are invalid, no error  
will be posted until an illegal access is made by some other command.  
Moves the read/ write heads from anywhere on the disk to cylinder 0.  
When this command is received, the drive:  
1. Sets BSY and  
2. Issues a seek to cylinder zero.  
The drive waits for the seek to complete, then the drive:  
1. Updates status,  
2. Resets BSY and  
3. Generates an interrupt.  
If the drive cannot reach cylinder 0, the Error bit is set in the Status register, and the Track 0 bit is set in the  
Error register.  
NOTE: If a maximum head and sector number is selected – such that the number of cylinders will exceed 65,535 – then  
the maximum cylinder value will be reduced to 65, 535.  
7 – 12  
INTERFACECOMMANDS  
S e e k , Fo rm a t a n d Dia g n o s t ic Co m m a n d s  
S e e k  
Initiates a seek to the track, and selects the head specified in the Command block.  
1. Sets BSY in the Status register,  
2. Initiates the Seek,  
3. Resets BSY and  
4. Generates an interrupt.  
The drive does not wait for the seek to complete before returning the interrupt. If a new command is issued  
to a drive during the execution of a Seek command, the drive will wait (with BSY active) for the Seek to  
complete before executing the new command.  
Fo rm a t Tra c k  
Formats the track specified in the Command Block. Shortly after the Command register is written, the drive  
sets the bit, and waits for the host to fill the sector buffer with the interleave table. When the buffer is full,  
the drive resets DRQ, sets BSY and begins command execution. If the drive is not already on the desired  
track, an implied seek is performed. Once at the desired track the data fields are written with all zeroes.  
Exe c u t e Drive Dia g n o s t ic  
Commands the drive to implement the internal diagnostic tests. (These tests are executed only upon  
command receipt; they do not run automatically at power up or after a reset.)  
The drive sets BSY immediately upon receiving this command. The following table presents the codes and  
their descriptions. Note that the value in the Error register should be viewed as a unique 8 bit Code.  
ERROR CODE  
DESCRIPTION  
01  
00  
No error detected  
Master drive failed  
Master and slave drives failed  
Slave drive failed  
80, 82  
81  
Note: If a slave drive fails diagnostics, the master drive ORs 80h with its own status, and loads that code into the Error  
register. If a slave drive passes diagnostics (or a slave is absent), the master drive ORs 00 with its own status and loads  
that code into the Error register.  
7 – 13  
INTERFACECOMMANDS  
S .M.A.R.T. Co m m a n d S e t  
Exe c u t e S .M.A.R.T.  
The Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.) command has been implemented to  
improve the data integrity and data availability of hard disk drives. In some cases, a S.M.A.R.T. capable device  
will predict an impending failure with sufficient time to allow users to backup their data and replace the  
drive before data loss or loss of service.  
The S.M.A.R.T. sub-commands (listed below) comprise the ATA S.M.A.R.T. feature set that provide access  
to S.M.A.R.T. attribute values, attribute thresholds and other logging and reporting information.  
Prior to writing a S.M.A.R.T. command to the device’s command register, key values must be written by the  
host into the device’s Cylinder Low and Cylinder High registers, or the command will be aborted. For any  
S.M.A.R.T. sub-command, if a device register is not specified as being written with a value by the host, then  
the value in that register is undefined and will be ignored by the device. The key values are:  
Key  
4Fh  
C2h  
Register  
Cylinder Low (1F4h)  
Cylinder High (1F5h)  
The S.M.A.R.T. sub-commands use a single command code (B0h) and are differentiated from one another  
by the value placed in the Features register. In order to issue a command, the host must write the sub-  
command-specific code to the device’s Features register before writing the command code to the command  
register. The sub-commands and their respective codes are:  
D0h  
D1h  
D2h  
S.M.A.R.T. Read Attribute Value  
This feature returns 512 bytes of attribute information to the host.  
S.M.A.R.T. Read Attribute Thresholds  
This feature returns 512 bytes of warranty failure thresholds to the host.  
Enable/Disable Autosave  
To enable this feature, set the sector count register to F1h (enable) or 0 (disable). Attribute values are  
automatically saved to non-volatile storage on the device after five minutes of idle time and before  
entering idle, sleep or standby modes. This feature is defaulted to “enabled” when S.M.A.R.T. is  
enabled via the S.M.A.R.T. Enable Operations commands. The autosave feature will not impact host  
system performance and does not need to be disabled.  
D3h  
D4h  
S.M.A.R.T. Save Attribute Value  
This feature saves the current attribute values to non-volatile storage.  
Perform Off-Line Data Collection  
Data is collected from random seeks, timed pattern seek times and head margin tests.  
D8h  
D9h  
DAh  
Enable S.M.A.R.T.  
Disable S.M.A.R.T.  
S.M.A.R.T. Return Status  
This feature allows the host to assess the status of a S.M.A.R.T. capable device by comparing all saved  
attribute values with their corresponding warranty failure thresholds. If no thresholds are exceeded, the  
drive is declared to have a positive health status. If any warranty failure threshold is exceeded, the drive  
is declared to have a negative health status. Executing this sub-command results in all attribute values  
being saved to non-volatile storage on the device.  
DBh  
Enable/Disable Automatic Off-Line  
To enable this feature, set the Sector Count register to F1h or 0 to disable.  
7 – 14  
SECTION 8  
ServiceandSupport  
Service Policy  
If a customer discovers a defect in a Maxtor hard drive, Maxtor will, at its option, repair or replace the disk  
drive at no charge to the customer, provided it is returned during the warranty period. Drives must be properly  
packaged in Maxtor packaging or Maxtor-approved packaging to obtain warranty service. Any unauthorized  
repairs or adjustments to the drive void the warranty.  
To consistently provide our customers with the best possible products and services, Maxtor developed the  
Total Customer Satisfaction (TCS) program. Through the ongoing TCS process, Maxtor employees take  
direct responsibility for every customer’s level of satisfaction – with Maxtor technology, price, quality,  
delivery, service and support.  
No Quibble Service®  
Another TCS feature is Maxtor’s No Quibble Service® policy. By minimizing paperwork and processing,  
No Quibble Service dramatically cuts the turnaround time normally required for repairs and returns.  
Here’s how it works:  
(RMA) number and provides a credit card number,  
2. Maxtor ships a replacement drive within 2 business days, and  
3. Customer returns the original drive and credit card draft is destroyed.  
Product Support  
Technical Assistance/Customer Service  
Hours of operation: 6 a.m. to 6 p.m. (Mountain Time) Monday through Friday.  
North, Central and South America Languages supported: English, Spanish  
Voice  
E-mail  
800-2MAXTOR (800-262-9867)  
Outside Continental USA  
303-678-2015  
Europe, Middle East, Africa  
Languages supported: English, French, German  
Hours of operation: 8:30 a.m. to 5 p.m. (Greenwich Mean Time) Monday through Thursday, 8:30 a.m.  
to 4 p.m. Friday.  
Voice  
E-mail  
Fax  
+ 353 1 204 1111  
+353 1 286 1419  
+ 353 1 204 1122  
MaxFax  
8 – 1  
SERVICE AND SUPPORT  
Asia/Pacific (APAC)  
Australia  
Vox  
Languages supported: English  
+ 61 2 9369 3662  
Fax  
+ 61 2 9369 2082  
MaxFax  
+ 61 2 9369 4733  
BBS  
+ 61 2 9369 4293  
Singapore  
Languages supported: English  
Contact local Maxtor sales office  
From  
Dial  
Australia  
Hong Kong  
Indonesia  
Japan  
South Korea  
Malaysia  
New Zealand  
Singapore Toll Free  
Singapore Vox  
Singapore Fax  
Taiwan  
1-800-124-328  
800-96-3387  
803-65-6500  
0031-65-3616  
0078-65-800-6500  
1-800-80-1126  
0800-44-6542  
1-800-481-6788  
65-8520220  
65-251744  
0080-65-1062  
001-800-65-6500  
Thailand  
MaxInfo Service  
Use a touch-tone phone to listen to technical information about Maxtor products and the top Q&A’s  
from our 24-hour automated voice system.  
Continental USA  
800-2MAXTOR (800-262-9867)  
Press 1, wait for announcement, listen for option  
303-678-2015, listen for option  
Outside Continental USA  
MaxFax® Service  
Use a touch-tone phone to order technical reference sheets, drive specifications, installation guides  
and other documents from our 24-hour automated fax retrieval system. Requested items are sent directly  
to your fax machine.  
Continental USA  
Phone  
Outside Continental USA  
Europe  
Languages supported: English  
800-2MAXTOR (800-262-9867), listen for option  
303-678-2618  
Language support: English, French, German  
+ 353 1 204 1122  
Phone  
Asia/Pacific (APAC)  
Phone  
Language support: English  
+ 61 2 9369 4733  
8 – 2  
GLOSSARY  
Glossary  
A
B
a c c e s s  
b a d b lo c k  
To obtain data from, or place data into, RAM, a register,  
or data storage device.  
A block that cannot store data because of a media flaw.  
bit  
a c c e s s t im e  
An abbreviation for binary digit, of which there are two (0  
and 1). A bit is the basic data unit of most digital  
computers. A bit is usually part of a data byte or word,  
but bits may be used singly to control or read logic “on-  
off” functions. The fundamental unit information, often  
used loosely to refer to a circuit or magnetization state at  
a particular instant in time.  
The interval between the issuing of an access command  
and the instant that the target data may be read or  
written. Access time includes seek time, latency and  
controller overhead time.  
a d d re s s  
A number, generally binary, distinguishing a specific  
member of an ordered set of locations. In disk  
engineering, the address may consist of drives (unit  
address), radial positions (cylinder address), or  
circumferential position (sector address).  
BIOS  
Acronym for Basic Input/Output System. The firmware  
area of a CPU that controls operations through the  
system bus and to the attached cards and peripheral  
devices.  
a llo c a t io n  
A process of assigning designated areas of the disk to  
particular files.  
BPI  
Acronym for bits per inch. See bit density.  
a lt e rn a t e t ra c k  
b lo c k  
A spare track used in the event that a normal track  
becomes damaged or is unusable.  
A group of bytes handled, stored, and accessed as a  
logical data unit, such as an individual file record.  
a n a lo g  
b u ffe r  
A signal or system that does not use digital states to  
convey information. A signal may have any number of  
significant states (values), contrasted to digital signals  
which can only have two states.  
A temporary data storage area that compensates for a  
difference in data transfer rates and/or data processing  
rates between sender and receiver.  
b u s  
ANSI  
A collection of functionally parallel conductors that forms  
an interconnection between functional blocks in a digital  
device. A length of parallel conductors that forms a major  
interconnection route between the computer system  
CPU (central processing unit) and its peripheral  
subsystems. Depending on its design, a bus may carry  
data, addresses, power, and more.  
American National Standards Institute.  
a p p lic a t io n p ro g ra m  
A sequence of programmed instructions that tell the  
computer how to perform some end-user task, such as  
accounting or word processing.  
a re a l d e n s it y  
b yt e  
Bit density (bits per inch) multiplied by track density  
(tracks per inch) or bits per square inch.  
An ordered collection of bits treated as a unit. Most  
often, a byte is understood to consist of eight bits. One  
byte is necessary to define an alphanumeric character.  
a s ym m e t ry  
A distortion of the readback signal which is shown in  
different intervals between the positive and negative  
voltage peaks.  
C
c a c h e  
a u xilia ry m e m o ry  
Random access memory (RAM) used as a buffer  
between the CPU and the disk drive.  
Memory other than main memory; generally a mass-  
storage subsystem containing disk drives and backup  
tape drives, controller(s) and buffer memory (also called  
peripheral memory).  
c a p a c it y  
The amount of data, usually expressed in bytes, which  
can be stored in a given device or portion of same.  
a ve ra g e a c c e s s t im e  
The average time to make all possible length accesses  
(seeks).  
a ve ra g e s e e k t im e  
The average time to make all possible length seeks. A  
typical measure of performance.  
GL – 1  
GLOSSARY  
c e n t ra l p ro c e s s in g u n it (CP U)  
D
The heart of the computer system that executes  
programmed instructions. It includes the arithmetic logic  
unit (ALU) for performing all math and logic operations, a  
control section for interpreting and executing  
instructions, internal memory for temporary storage of  
program variables and other functions.  
d a t a  
An ordered collection of information. In a specific case, it  
is the information processed by a computer.  
d a t a s e p a ra t o r  
An electronic circuit which decodes playback data and  
produces separate clock and data bits. Sometimes  
incorrectly used to denote data synchronizer.  
c h a n n e l  
A collection of electronic circuits used in the process of  
writing and reading information to and from magnetic  
media.  
d a t a s yn c h ro n ize r  
An electronic circuit producing a clock signal that is  
synchronous with the incoming data stream. This clock  
signal is then used to decode the recording code being  
used into user data.  
c h a ra c t e r  
An ordered collection of bits representing one of a set of  
predefined symbols. Often the term is used  
interchangeably with byte, but this is inexact.  
d a t a t ra n s fe r ra t e  
c lo s e d lo o p  
In a disk or tape drive, the rate at which data is  
transferred to or from the storage media. It is usually  
given in thousands of bits per second (Kbit/second) or  
millions of bits per second (Mbit/second).  
A control technique that enables the positioning system  
to correct off-track errors in real time. The actual head  
position is monitored and compared to the ideal track  
position to determine any position error that might be  
occurring. This information is then used to produce a  
correction signal (feedback) that goes to the positioner to  
correct the error. (See also track following servo).  
d e d ic a t e d la n d in g zo n e  
A designated radial zone on the disk where contact  
starting and stopping occur by design.  
c lo s e d lo o p s e rvo  
d e d ic a t e d s e rvo  
A servo control technique that uses position feedback to  
correct off-track errors. See Track Following Servo.  
A servo scheme in which a prerecorded pattern on an  
otherwise unused disk surface provides position  
information to the servo circuitry by means of a head  
reading that surface.  
c lu s t e r  
The smallest allocatable unit of disk storage allowed by  
MS-DOS; each FAT entry represents one cluster.  
d e fe c t  
A magnetic imperfection in a recording surface.  
c o n t ro lle r  
An electronic device for connecting one or more mass  
storage peripherals (rigid disk drives, tape drives, and  
optical disk drives) to the input/output circuits of a host  
computer. Controllers vary in complexity, with more  
sophisticated units able to buffer and schedule  
commands, correct data errors, and bypass media  
defects without host intervention.  
d e fe c t m a n a g e m e n t  
A general methodology of avoiding data errors on a  
recording surface by avoiding the use of known bad  
areas of media. Usually defective sectors or tracks are  
retired and data are written in alternate locations. Several  
algorithms are possible such as “sector slipping,” or  
“spare sector per track.”  
c o n t ro lle r  
d e fe c t m a p  
A miniature CPU dedicated to controlling a peripheral  
device, such as a disk drive, tape drive, video display  
terminal, or printer. The controller executes commands  
from the central processing unit and reissues commands  
to the peripheral device.  
A list of defects that fall within a pass/fail criteria of a user.  
This list is usually used by an operating system or a disk  
drive controller for defect management.  
d e fe c t s k ip p in g  
A defect management scheme for avoiding surface  
defects. It has data written before and after the defect,  
instead of using alternate tracks or sectors to avoid use  
of the defective area.  
c o rre c t a b le e rro r  
An error that can be overcome by the use of Error  
Detection and Correction.  
c ylin d e r  
d e n s it y  
On several disk surfaces sharing a common rotational  
axis, the aggregate of tracks at a given radial position. A  
set of disk tracks that are simultaneously under the set of  
read/write heads. This three-dimensional storage volume  
can be accessed after a single seek.  
Generally, recording density. See areal, bit, and storage  
density.  
DC e ra s e  
The method of erasing a track using a DC write/erase  
current through either a Read/Write or Erase head.  
c ylin d e r ze ro  
The outermost cylinder in a drive that can be used for  
data storage.  
d ig it a l  
Any system that processes digital binary signals (having  
only values of a 1 or 0; usually in bits and bytes) rather  
than analog signals (signals that can have many values)  
GL – 2  
GLOSSARY  
d ig it a l m a g n e t ic re c o rd in g  
e rro r c o rre c t io n c o d e (ECC)  
See magnetic recording.  
A mathematical algorithm that can detect and correct  
errors in a data field. This is accomplished with the aid of  
Check Bits added to the raw data.  
d ire c t a c c e s s  
Access directly to memory location. (See random  
access).  
e rro r fre e  
A recording surface that has no defects.  
d ire c t m e m o ry a c c e s s (DMA)  
A mean of data transfer between the device and host  
memory without processor intervention.  
e rro r ra t e  
The number of errors (type must be specified) that occur  
in a specified number of bits read.  
d ire c t o ry  
A listing of files maintained by the disk operation system  
(DOS) or a data base management system to enable a  
user to quickly access data files.  
e rro r re c o ve ry p ro c e d u re  
The process that occurs in response to a data error. In a  
drive without ECC, this would include re-calibration and  
re-seeking to the specified track and rereading the  
specified data.  
d is k  
A flat, circular piece of metal (usually aluminum) or plastic  
(usually mylar) with a magnetic coating upon which  
information can be recorded. (See, for example, floppy  
disk or Winchester disk)  
e xt ra p u ls e  
Term used in surface certification. It is when a flux field  
discontinuity remains after the recording surface is  
erased, thereby producing an electrical output of a read  
head passing over the area with the discontinuity. An  
extra pulse occurs when the electrical output is larger  
than a specified threshold.  
d is k d rive o r d is k m e m o ry d e vic e  
The total electromechanical storage device containing  
disks and read/write heads, head positioning mechanism,  
drive motor, and electronics.  
F
d is k p a c k  
A number of metal disks packaged in a canister for  
removal from the disk drive (predecessor of Winchester  
technology).  
fe e d b a c k  
In a closed-loop system, the output signal (from the  
servo head) is used to modify the input signal (to the  
positioner).  
d is k o p e ra t in g s ys t e m (DOS )  
The master computer system program that schedules  
tasks, allocates the computer system resources, controls  
accesses to mass storage devices, manages files, and so  
forth. Typical disk operating systems include CP/M, MS-  
DOS, and UNIX.  
fe t c h  
A read operation and its related data transfer operations.  
file a llo c a t io n t a b le (FAT)  
Allocates space on the disk for files, one cluster at a  
time; locks out unusable clusters; identifies unused (free)  
area; and lists a file’s location. With two FAT’s present,  
the second copy ensures consistency and protects  
against loss of data if one of the sectors on the first FAT  
is damaged.  
d is k s t o ra g e  
Auxiliary memory system containing disk drives.  
d is k t ra n s fe r ra t e  
The rate that digital data is transferred from one point to  
another. Expressed in either bits/second or bytes/  
second.  
flu x c h a n g e s p e r in c h  
Synonymous with frpi (flux reversals per inch). Only in  
MFM recording does 1 fci equal 1 bpi (bit per inch). In  
run-length-limited encoding schemes, generally 1 fci  
equals 1.5 bpi.  
d o u b le fre q u e n c y e n c o d in g  
Another name for FM encoding. This is because all  
possible data combinations will result in only two  
possible temporal displacements of adjacent data bits,  
specifically “1F” and 2F.”  
fo rm a t  
In a disk drive, the arrangement of data on a storage  
media. A standard 5.25-inch disk format consists of 17,  
26, or 36 sectors per track, and 512 bytes of data per  
sector, plus identification, error correction, and other  
bytes necessary for accessing and synchronizing data.  
E
e a rly w in d o w  
A data window that has been intentionally shifted in time  
in an early direction.  
fo rm a t t e d c a p a c it y  
The actual capacity available to store data in a mass  
storage device. The formatted capacity is the gross  
capacity, less the capacity taken up by the overhead data  
used in formatting the sectors.  
e m b e d d e d s e rvo  
A servo technique used for track following. Position  
information is prerecorded between data areas in a track  
so that a data head, and proper additional circuitry, can  
determine the data head location with respect to the  
center position of the track (or cylinder) in question.  
fre q u e n c y m o d u la t io n  
A recording code. A flux reversal at the beginning of a  
cell time represents clock bit; a “1” bit is a flux reversal at  
the center of the cell time, and a “0” bit is an absence of  
a flux reversal.  
e ra s e  
A process by which a signal recorded on a medium is  
removed and the medium made ready for rerecording.  
GL – 3  
GLOSSARY  
fre q u e n c y re s p o n s e  
in it ia liza t io n  
A measure of how effectively a circuit or device transmits  
the different frequencies applied to it. In disk and tape  
drives this refers to the read/write channel. In disk drives,  
it can also refer to the dynamic mechanical characteristics  
of a positioning system.  
Applying input patterns or instructions to a device so that  
all operational parameters are at a known value.  
in p u t  
Data entering the computer to be processed; also user  
commands.  
G
in p u t /o u t p u t (I/O)  
The process of entering data into or removing data from  
a computer system or a peripheral device.  
g ig a b yt e (GB)  
One billion bytes (one thousand megabytes) or 10E9.  
in t e llig e n t p e rip h e ra l  
A peripheral device that contains a processor or  
microprocessor to enable it to interpret and execute  
commands.  
H
h a rd e rro r  
in t e rfa c e  
An error that is not able to be overcome by repeated  
readings and repositioning means.  
The data transmitters, data receivers, logic, and wiring  
that link one piece of computer equipment to another,  
such as a disk drive to a controller or a controller to a  
system bus.  
h a rd s e c t o re d  
A technique where a digital signal indicates the  
beginning of a sector on a track. This is contrasted to soft  
sectoring, where the controller determines the beginning  
of a sector by the reading of format information from the  
disk.  
in t e rfa c e s t a n d a rd  
The interface specifications agreed to by various  
manufacturers to promote industry-wide  
interchangeability of products such as a disk drive.  
Interface standards generally reduce product costs,  
allows buyers to purchase from more than one source,  
and allow faster market acceptance of new products.  
h e a d  
The electromagnetic device that write (records), reads  
(plays back), and erases data on a magnetic media. It  
contains a read core(s) and/or a write core(s) and/or erase  
core(s) which is/are used to produce or receive magnetic  
flux. Sometimes the term is all inclusive to mean the  
carriage assembly which includes the slider and flexure.  
in t e rle a ve  
An ordering of physical sectors to be skipped between  
logical sectors on your hard disk.  
I/O p ro c e s s o r  
h e a d c ra s h  
Intelligent processor or controller that handles the input/  
output operations of a computer.  
The inadvertent touching of a disk by a head flying over  
the disk (may destroy a portion of the media and/or the  
head).  
in t e rru p t  
A signal, usually from a subsystem to a central  
processing unit, to signify that an operation has been  
completed or cannot be completed.  
h e a d d is k a s s e m b ly (HDA)  
The mechanical portion of a rigid, fixed disk drive. It  
usually includes disks, heads, spindle motor, and  
actuator.  
J
h e a d lo a d in g zo n e  
The non-data area on the disk set aside for the controlled  
takeoff and landing of the Winchester heads when the  
drive is turned on and off. Dedicated annulus on each  
disk surface in which heads are loaded, unloaded, or  
flying height is established. Head-disk contact may occur  
in some instances; no data is recorded in this area.  
ju m p e r  
A small piece of plastic that slides over pairs of pins that  
protrude from the circuit board on the hard drive to make  
an electrical connection and activate a specific option.  
K
h e a d p o s it io n e r  
Also known as actuator, a mechanism that moves the  
arms that carry read/write heads to the cylinder being  
accessed.  
k ilo b yt e (KB)  
A unit of measure of approximately 1,000 bytes.  
(However, because computer memory is partitioned into  
sizes that are a power of two, a kilobyte is really 1,024  
bytes.)  
I
in d e x  
L
Similar to a directory, but used to establish a physical to  
logical cross reference. Used to update the physical disk  
address (tracks and sectors) of files and to expedite  
accesses.  
la n d in g zo n e o r Lzo n e  
The cylinder number/location to where the read/write  
head(s) move upon power down.  
in s id e d ia m e t e r  
The smallest radial position used for the recording and  
playback of flux reversals on a magnetic disk surface.  
la t e b it  
A bit that is in the late half of the data window.  
GL – 4  
GLOSSARY  
la t e w in d o w  
m is s in g p u ls e  
A data window that has been shifted in a late direction to  
facilitate data recovery.  
A term used in surface certification. It is when a  
prerecorded signal is reduced in amplitude by a certain  
specified percentage.  
la t e n c y  
A delay encountered in a computer when waiting for a  
specific response. In a disk drive there is both seek  
latency and rotational latency. The time required for the  
addressed sector to arrive under the head after the head  
is positioned over the correct track. It is a result of the  
disk’s rotational speed and must be considered in  
determining the disk drive’s total access time.  
m o d ifie d fre q u e n c y m o d u la t io n (MFM)  
A method of encoding digital data signals for recording  
on magnetic media. Also called “three frequency  
recording.” Recording code that only uses synchronizing  
clock pulse if data bits are not present. Doubles the lineal  
bit density without increasing the lineal flux reversal  
density, compared to Frequency Modulation.  
lo g ic  
m o d ifie d m o d ifie d fre q u e n c y m o d u la t io n (MMFM)  
A recording code similar to MFM that has a longer run  
length limited distance.  
Electronic circuitry that switches on and off (“1” and “0”)  
to perform functions.  
lo g ic a l a d d re s s  
m o d u la t io n  
A storage location address that may not relate directly to  
a physical location. Usually used to request information  
from a controller, which performs a logical to physical  
address conversion, and in turn, retrieves the data from a  
physical location in the mass storage peripheral.  
1. Readback voltage fluctuation usually related to the  
rotational period of a disk. 2. A recording code, such as  
FM, MFM, or RLL, to translate between flux reversals  
and bits or bytes.  
N
lo g ic a l b lo c k a d d re s s in g  
Defines the addressing of the device by the linear  
mapping of sectors.  
n o n -re t u rn t o ze ro  
A form of data encoding that is not self-clocking, in other  
words, it needs to be provided with an external bit cell  
clock signal. Generally used in higher-performance disk  
drives.  
lo g ic a l s e c t o r  
The lowest unit of space that DOS can access through a  
device driver; one or more physical sectors.  
lo w fre q u e n c y  
O
The lowest recording frequency used in a particular  
magnetic recording device. With FM or MFM channel  
codes, this frequency is also called “IF.”  
o ff-lin e  
processing or peripheral operations performed while  
disconnected from the system CPU via the system bus.  
M
o n -lin e  
m a in m e m o ry  
processing or peripheral operations performed while  
disconnected from the system CPU via the system bus.  
Random-access memory (RAM) used by the central  
processing unit (CPU) for storing program instructions  
and data currently being processed by those instructions.  
(See also random access memory.)  
o p e n lo o p s e rvo  
A head positioning system that does not use positional  
information to verify and correct the radial location of the  
head relative to the track. This is usually achieved by use  
of a stepper motor which has predetermined stopping  
point that corresponds to track locations.  
m a s s s t o ra g e  
Auxiliary memory used in conjunctions with main  
memory; generally having a large, on-line storage  
capacity.  
o p e ra t in g s ys t e m  
m e g a b yt e (MB)  
A unit of measure approximately one million bytes  
(actually 1,048,576 bytes) or 10E6.  
A software program that organizes the actions of the  
parts of the computer and its peripheral devices. (See  
disk operating system.)  
m e m o ry  
o u t s id e d ia m e t e r  
Any device or storage system capable of storing and  
retrieving information. (See also storage definitions.)  
The largest radius recording track on a disk.  
o ve rw rit e  
m ic ro c o m p u t e r  
A test that measures the residual 1F recorded frequency  
on a track after being overwritten by a 2F signal.  
Variations of the test exist.  
A computer whose central processing unit is a  
microprocessor. It is usually, but not necessarily, desktop  
size.  
m ic ro p ro c e s s o r  
A central processing unit (CPU) manufactured as a chip or  
a small number of chips.  
GL – 5  
GLOSSARY  
p ro c e s s in g  
P
The process of the computer handling, manipulating and  
modifying data such as arithmetic calculation, file lookup  
and updating, and word pressing.  
p a ra lle lis m  
1. The condition of two planes or lines being parallel.  
Important in disk drives because a lack of it in mechanical  
assemblies can result in positioning inaccuracy. More  
precisely: planes-coplanar; lines-colinear. 2. Is the local  
variation in disk thickness measured independently of  
thickness itself. 3. The ability of a multiprocessor  
computer to allocate more than one processor (CPU) to a  
computing problem, where each CPU works on a  
separate problem or separate segment of that problem.  
Also referred to as parallel processing.  
p u ls e c ro w d in g  
Modification of playback amplitude due to super-  
positioning of adjacent flux reversal fields being sensed  
by the read/write gap.  
p u ls e d e t e c t  
A digital pulse train in which each leading edge or each  
edge corresponds to a magnetic transition read from the  
disk. If transition qualification circuitry exists in the drive,  
this signal is the output of same. Also known as  
transition detect.  
p a rit y  
A simple method of data error detections that always  
makes numbers either odd or even, using an extra bit in  
which the total number of binary 1s (or 0s) in a byte is  
always odd or always even; thus, in an odd parity  
scheme, every byte has eight bits of data and one parity  
bit. If using odd parity and the number of 1 bits  
comprising the byte of data is not odd, the ninth or parity  
bit is set to 1 to create the odd parity. In this way, a byte  
of data can be checked for accurate transmission by  
simply counting the bits for an odd parity indication. If the  
count is ever even, an error is indicated.  
R
ra n d o m a c c e s s m e m o ry (RAM)  
Memory designed so that any storage location can be  
accessed randomly, directly and individually. This is  
contrasted to sequential access devices such as tape  
drives.  
re a d  
To access a storage location and obtain previously  
recorded data. To sense the presence of flux reversals  
on magnetic media. Usually implemented such that a  
dynamic flux amplitude will cause a proportional electrical  
output from the transducer.  
p a rt it io n  
A logical section of a disk drive, each of which becomes  
a logical device with a drive letter.  
p e a k s h ift  
re a d g a t e s ig n a l  
A digital input signal which causes the drive circuitry to  
recover data.  
The shifting in time of the zero-slope portion of a  
readback voltage from the values contained in the write  
current waveform. Sometimes incorrectly used to  
describe bit jitter.  
re a d o n ly m e m o ry (ROM)  
A form of memory which cannot be changed in formal  
operational modes. Many different types are available.  
RAM is used for permanent information storage.  
Computer control programs are often stored in ROM  
applications.  
p e rip h e ra l e q u ip m e n t  
Auxiliary memory, displays, printers, and other equipment  
usually attached to a computer system’s CPU by  
controllers and cables. (They are often packaged  
together in a desktop computer.)  
re a d /w rit e h e a d  
p h a s e lo c k e d lo o p (P LL)  
The recording element which writes data to the magnetic  
media and reads recorded data from the media.  
A circuit whose output locks onto and tracks the  
frequency of an input signal. Sometimes incorrectly  
called a data separator.  
re -c a lib ra t e  
The action of moving the head of a disk drive to cylinder  
zero.  
p h a s e m a rg in  
Measure in degrees of the amount of difference  
between excursions from the window center where flux  
reversals can occur and the edge of the data window.  
Similar to window margin.  
re c o ve ra b le e rro r  
A read error, transient or otherwise, falling within the  
capability of an ECC mechanism to correct, or able to  
overcome by rereading the data in question.  
p h ys ic a l s e c t o r  
The smallest grouping of data on the hard disk; always  
512 bytes.  
ro t a t io n a l la t e n c y  
The amount of delay in obtaining information from a disk  
drive attributable to the rotation of the disk.  
PIO  
Programmable Input Output. A means of accessing  
device registers. Also describes one form of data  
transfers. PIO data transfers are performed by the host  
processor using PIO register accesses to the data  
register.  
ru n -le n g t h lim it e d  
An encoding process that repositions data bits and limits  
the length of zero bits in order to compress information  
being stored on disks.  
ru n -le n g t h lim it e d e n c o d in g  
A recording code. Sometimes meant to denote “2.7  
RLL” which can signify 1.5 times the bits as MFM, given  
the same number of flux reversals in a given lineal  
distance.  
p la t e d t h in film m e d ia  
Magnetic disk memory media having its surface plated  
with a thin coating of a metallic alloy instead of being  
coated with oxide.  
GL – 6  
GLOSSARY  
s e rvo t ra c k  
S
A track on a servo surface. The prerecorded reference  
track on the dedicated servo surface of a disk drive. All  
s e c t o r  
data track positions are compared to their corresponding  
servo track to determine “off track”/”on track” position.  
A logical segment of information on a particular track. The  
smallest addressable unit of storage on a disk. Tracks are  
made of sectors.  
s e t t lin g t im e  
The time it takes a head to stop vibrating, within  
specified limits, after it reaches the desired cylinder.  
s e c t o r p u ls e s ig n a l  
A digital signal pulse present in hard sectored drives  
which indicates the beginning of a sector. Embedded  
servo pattern or other prerecorded information may be  
present on the disk when sector is active.  
s ilic o n  
Semiconductor material generally used to manufacture  
microprocessors and other integrated circuit chips.  
s e e k  
s m a ll c o m p u t e r s ys t e m in t e rfa c e (S CS I)  
An intelligent interface that incorporates controller  
functions directly into the drive.  
A random access operation by the disk drive. The act of  
moving a set of read/write heads so that one of them is  
over the desired cylinder. The actuator or positioner  
moves the heads to the cylinder containing the desired  
track and sector.  
S .M.A.R.T. c a p a b ilit y  
Self-Monitoring Analysis and Reporting Technology.  
Prediction of device degradation and/or faults.  
s e e k c o m p le t e s ig n a l  
A digital signal level which indicates that the positioner is  
not moving and is located over a cylinder or offset  
position.  
s o ft e rro r  
A data error which can be overcome by rereading the  
data or repositioning the head.  
s e e k t im e  
s o ft s e c t o re d  
The amount of time between when a step pulse or seek  
command is issued until the head settles onto the  
desired cylinder. Sometimes is measured without settling  
times.  
A technique where the controller determines the  
beginning of a sector by the reading of format  
information from the disk. This is contrasted to hard  
sectoring where a digital signal indicates the beginning of  
a sector on a track.  
s e q u e n t ia l a c c e s s  
The writing or reading of data in a sequential order such  
as reading data blocks stored one after the other on  
magnetic tape. This is contrasted to random access of  
information.  
s o ft w a re  
Applications programs, operating systems, and other  
programs (as opposed to hardware).  
s p in d le  
s e rvo b u rs t  
The rotating hub structure to which the disks are  
attached.  
A momentary servo pattern used in embedded servo  
control systems usually positioned between sectors or at  
the end of a track.  
s p in d le m o t o r  
The motor that rotates the spindle and therefore the  
disks.  
s e rvo c o n t ro l  
A technique by which the speed or position of a moving  
device is forced into conformity with a desired or  
standard speed or position.  
s p u t t e re d m e d ia  
Magnetic disk or tape that has the magnetic layer  
deposited by sputtering means.  
s e rvo h e a d  
A magnetic head designed specifically for accurately  
reading servo data.  
s t e p p e r m o t o r  
A motor that has known detent positions where the rotor  
will stop with the proper control in some cases. The  
digitally controlled motor moves the head positioner from  
track to track in small, step-like motions.  
s e rvo p a t t e rn  
A readback signal that indicates the position of a head  
relative to a track.  
s t o ra g e c a p a c it y  
s e rvo s u rfa c e  
The amount of data that can be stored in a memory  
location, usually specified in kilobytes for main memory  
and floppy drives and megabytes for mass storage  
devices.  
A recording surface in a multi-surface disk drive that only  
contains control information which provides timing, head  
position, and track-following information for the data  
surfaces.  
s t o ra g e d e n s it y  
s e rvo s ys t e m  
Usually refers to recording density (BPI, TPI, or a  
combination of the two.)  
An automatic system for maintaining the read/write head  
on track; can be either “open loop,” “quasi-closed  
loop,” or “closed loop.”  
s t o ra g e lo c a t io n  
A memory location, identified by an address where  
information may be read or written.  
GL – 7  
GLOSSARY  
s t ro b e o ffs e t s ig n a l  
W
A group of digital input signal levels which cause the  
read PLL and/or data decoder to shift the decoding  
windows by fractional amounts. Often early/late are  
modified when two signals are used.  
Wh it n e y h e a d  
A successor to the original Winchester read/write head  
design. The primary change was to make the flexure  
smaller and more rigid. First used in IBM 3370/3380.  
T
Wh it n e y t e c h n o lo g y  
t h in -film h e a d  
A method of constructing a read/write head in a rigid disk  
drive using a Whitney head. In all other details it is the  
same as Winchester technology.  
A magnetic transducer manufactured by deposition of  
magnetic and electrical materials on a base material  
contrasted with prior art mechanical methods. Read/write  
heads whose read/write element is deposited using  
integrated circuit techniques rather than being manually  
wound.  
Win c h e s t e r h e a d  
The read/write head used in Winchester technology,  
non-removable media disk drives. May be either a  
monolithic or composite type. It is aerodynamically  
designed to fly within microinches of the disk surface.  
t h in -film m e d ia  
See plated thin film media.  
Win c h e s t e r t e c h n o lo g y  
t ra c k  
A method of constructing a rigid disk drive using  
concepts introduced in the IBM model 3340 disk drive.  
The primary changes from prior technology was to lower  
the mass of the slider, use of a monolithic slider, radically  
changing the design of the flexure and having the slider  
come to rest on a lubricated disk surface when disk  
rotation ceases. In addition to the above, a totally sealed  
chamber containing the read/write heads and disks was  
used to protect against contamination.  
One surface of a cylinder. A path which contains  
reproducible information left on a magnetic medium by  
recording means energized from a single channel.  
t ra c k -fo llo w in g s e rvo  
A closed-loop positioner control system that continuously  
corrects the position of the disk drive’s heads by utilizing  
a reference track and a feedback loop in the head  
positioning system. (See also closed loop.)  
w in d o w m a rg in  
t ra c k s p e r in c h (TP I)  
A measurement of radial density. Tracks per inch of disk  
radius.  
The amount of tolerance a read/write system has for  
transition jitter at a specified error rate level.  
w o rd  
t ra c k p o s it io n in g  
A number of bits, typically a multiple of eight, processed  
in parallel (in a single operation). Standard word lengths  
are 8, 16, 32 and 64 bits (1, 2, 4, or 8 bytes).  
The method, both mechanical and electrical, used to  
position the heads over the correct cylinder in a disk  
drive system.  
w rite  
The recording of flux reversals on a magnetic media.  
U
w rit e p re -c o m p e n s a t io n  
The intentional time shifting of write data to offset the  
effects of bit shift in magnetic recording.  
u n -c o rre c t a b le e rro r  
An error that is not able to be overcome with Error  
Detection and Correction.  
w rit e g a t e s ig n a l  
A digital input signal level which causes the drive circuitry  
to record (write) data.  
u n fo rm a t t e d c a p a c it y  
Storage capacity of disk drive prior to formatting; also  
called the gross capacity. (See format.) The raw capacity  
of a drive not taking into account the capacity loss due to  
storage of the format control information on the disk  
surfaces.  
u n re c o ve ra b le e rro r  
A read error falling outside the capability of an ECC  
mechanism to correct, or not able to be overcome by  
rereading the data in question, with or without  
repositioning the head.  
V
vo ic e c o il m o t o r  
A positioning motor that uses the same principle as a  
voice coil in a loudspeaker. The motor has no detent  
positions. The mechanical motion output of it can be  
either rotary or linear.  
GL – 8  

Memorex MSP CR1100 User Manual
Maxtor MaxAttach NAS 4000 Series User Manual
Kenwood KDC W3534 User Manual
Hitachi Deskstar IC35L060AVV207 0 User Manual
Cypress HOTLink II CYV15G0104TRB User Manual
Classe Audio CDP 502 User Manual
Casio GQ 50 User Manual
Black &amp; Decker AM7 User Manual
APC Smart UPS 2200 VA User Manual
ABB RCRP 02 User Manual