Seagate ST3780A User manual

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Medalist Family:
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ST3780A, ST31220A
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AT Interface Drives
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Product Manual
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Medalist Family:
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ST3780A, ST31220A
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AT Interface Drives
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Product Manual
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© 1994 Seagate Technology, Inc. All rights reserved
Publication Number: 36260-001, Rev. A
June 1994
Seagate®, Seagate Technology®and the Seagate logo are registered
trademarks of Seagate Technology, Inc. Medalistis a trademark of
Seagate Technology,Inc. Other productnames aretrademarks or regis-
tered trademarks of their owners.
Seagate reserves the right to change, without notice, product offerings
or specifications. No part of this publication may be reproduced in any
form without written permission from Seagate Technology, Inc.

Contents
1.0 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Formatted capacity . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.1 ST3780A configurations . . . . . . . . . . . . . . . . . 2
1.1.2 ST31220Aconfigurations . . . . . . . . . . . . . . . . . 2
1.1.3 Physical organization . . . . . . . . . . . . . . . . . . . 2
1.2 Functional specifications . . . . . . . . . . . . . . . . . . . . 3
1.3 Seek time . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3.1 Multisegmented cache buffer . . . . . . . . . . . . . . . 4
1.4 Start/stop time . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5 Typical power-up and power-down sequence . . . . . . . . . 5
1.5.1 Power-up sequence . . . . . . . . . . . . . . . . . . . . 5
1.5.2 Power-down sequence . . . . . . . . . . . . . . . . . . 5
1.5.3 Auto-park . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.6 Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.7 Physicaldimensions . . . . . . . . . . . . . . . . . . . . . . 6
1.8 Environmental specifications . . . . . . . . . . . . . . . . . . 6
1.8.1 Ambient temperature . . . . . . . . . . . . . . . . . . . 6
1.8.2 Temperature gradient . . . . . . . . . . . . . . . . . . . 6
1.8.3 Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.8.4 Relative humidity . . . . . . . . . . . . . . . . . . . . . 7
1.9 Acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.10 Shock and vibration . . . . . . . . . . . . . . . . . . . . . . 7
1.11 DC Power . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.11.1 Input noise . . . . . . . . . . . . . . . . . . . . . . . . 8
1.11.2 Power management . . . . . . . . . . . . . . . . . . . 8
1.11.3 Idle and Standby modes . . . . . . . . . . . . . . . . . 9
1.11.4 Power-management modes . . . . . . . . . . . . . . . 9
1.11.5 Power consumption . . . . . . . . . . . . . . . . . . 10
1.12 Agency listings . . . . . . . . . . . . . . . . . . . . . . . 11
Medalist Family AT Product Manual, Rev. A iii

1.13 FCC verification . . . . . . . . . . . . . . . . . . . . . . 12
2.0 Configuring and mounting the drive . . . . . . . . . . . . . 15
2.1 Handling and static-discharge precautions . . . . . . . . . 15
2.2 I/O cable and connector . . . . . . . . . . . . . . . . . . 16
2.3 Remote LED connection . . . . . . . . . . . . . . . . . . 17
2.4 Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.4.1 Jumper sizes . . . . . . . . . . . . . . . . . . . . . . 17
2.4.2 Dual-drive emulation jumper block (J6) . . . . . . . . . 19
2.4.3 Master/slave configuration . . . . . . . . . . . . . . . 19
2.5 Cable select option . . . . . . . . . . . . . . . . . . . . . 20
2.6 Mounting the drive . . . . . . . . . . . . . . . . . . . . . . 21
3.0 AT interface . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.1 Command set . . . . . . . . . . . . . . . . . . . . . . . . 23
3.1.1 Identify Drive command (ECH) . . . . . . . . . . . . . 25
3.1.2 Set Features command (EFH) . . . . . . . . . . . . . 27
3.1.3 Sleep command (99H, E6H) . . . . . . . . . . . . . . 29
3.2 AT Interface connector pin assignments . . . . . . . . . . 29
Appendix. Timing diagrams . . . . . . . . . . . . . . . . . . . . . 31
iv Medalist Family AT Product Manual, Rev. A

Figures
Figure 1. Typical startup current profile . . . . . . . . . . . . . 11
Figure 2. AT interface connector . . . . . . . . . . . . . . . . . 16
Figure 3. Configuration jumpers . . . . . . . . . . . . . . . . . 18
Figure 4. Connecting cable-selected drives . . . . . . . . . . . 20
Figure 5. Mounting dimensions . . . . . . . . . . . . . . . . . . 22
Figure 6. AT interface connector pin assignments . . . . . . . 30
Figure 7. Programmed I/O timing without IORDY . . . . . . . . 31
Figure 8. Programmed I/O timing with IORDY . . . . . . . . . . 32
Figure 9. Multiword DMA timing . . . . . . . . . . . . . . . . . 33
Medalist Family AT Product Manual, Rev. A v

1.0 Specifications
1.1 Formatted capacity
The drive was low-level formatted at the factory. You cannot low-level
format it.
The drive was configured in translation mode at the factory. You can
verify the numberof cylinders,sectors per track and heads, and the total
number of sectors by using the Identify Drive (ECH) command. See
Section 3.1.1 for details about the Identify Drive command.
The amount of disc space that your computer can access depends on
the type of computer you have and the type of operating system or
third-partyinstallation softwarethatisused tohigh-levelformatST31220
family drives.
Your computer may support one of two addressing schemes to access
data on a hard disc—logical block addressing (LBA) or cylinder-head-
sector addressing (CHS). LBA allows you to access the full capacity of
your hard disc. CHS, which is used on older DOS systems, limits the
capacity of your harddisc to1,024cylinders (approximately 512Mbytes)
unless:
•You are using third-party installationsoftwarethat supportsmorethan
1,024 cylinders.
•You have configured your system to support dual-drive emulation (see
page 19).
•You have a host adapter (controller card) that supports more than
1,024 cylinders.
The relationship between sectors, heads and cylinders and the total
number of sectors per drive is shown in the following equation:
(sectors) ×(heads) ×(cylinders) < total sectors per drive
Medalist Family AT Product Manual, Rev. A 1

1.1.1 ST3780A configurations
CHS LBA
Cylinders 1,399 N/A
Heads 16 N/A
Sectors 63 N/A
Total sectors 1,410,192 1,410,864
Formatted capacity (Mbytes1) 722.02 722.36
1. One Mbyte equals one million bytes.
1.1.2 ST31220A configurations
CHS LBA
Cylinders 2,099 N/A
Heads 16 N/A
Sectors 63 N/A
Total sectors 2,115,792 2,116,296
Formatted capacity (Mbytes1) 1,083.2 1,083.5
1. One Mbyte equals one million bytes.
1.1.3 Physical organization
ST3780A ST31220A
Read/write heads 4 6
Discs 2 3
2 Medalist Family AT Product Manual, Rev. A

1.2 Functional specifications
Interface ATA
Zone Bit Recording method RLL (1,7)
External data burst transfer rate,
DMA Mode 2 (Mbytes per sec) 16.61
External data burst transfer rate,
PIO Mode 4 (Mbytes per sec) 16.62
Internal data transfer rate
(Mbits per sec) 27.92 to 47.24
Spindle speed (RPM) 4,500 ±0.5%
Cache size (Kbytes) 256
Cylinders 3,876
Bytes per sector 512
Recording density, max (BPI) 70,101
Track density (TPI) 4,250
1. The drives achieve this external transfer rate when using multiword
DMA mode 2; see Figure 9 on page33.
2. See Figure 8 on page32.
Medalist Family AT Product Manual, Rev. A 3

1.3 Seek time
Seek time is the interval between the time the actuator begins to move
and the time the head has settled over the target track. Seek time is a
true statistical average of at least 5,000 measurements of seek time. All
measurements are taken under nominal conditions of temperature and
voltage with the drive mounted horizontally. The specifications in the
table below are defined as follows:
•Track-to-track seek time is the average of all possible single-track
seeks in both directions.
•Average seek time ismeasured by executingseeks in both directions
between random cylinders.
•Full-stroke seek time is half the time needed to seek from track 0 to
the maximum track and back to track 0.
Track-to-track
seek time Average/typical seek time Full-stroke seek time Average latency
3.5 msec typ
4.5 msec max 12.0 msec read 14.0 msec write 25.0 msec typ 27.0 msec max 6.67 msec
Note. Host overhead varies between systems and cannot be specified.
Driveinternaloverhead is measuredby issuingano-motionseek.
Overheadis typically less than 0.5 msec.
1.3.1 Multisegmented cache buffer
The drive uses the 256-Kbyte multisegmented cache buffer to improve
performance by eliminating access times under certain conditions.
Readlook-ahead. The drive uses the read segments to store additional
logical sectors, after the last requested sector, into a buffer before the
computer requests the additional sectors. The cache buffer stores data
from the start of a read until the buffer segment is full or until another
command is received.
Write immediate. The drive uses the write segment to store write
commands and data. After the drive receives all of the data for the
command, it issues a write complete. Then, the drive writes the data to
the disc.
Write merging. The drive accepts contiguous write commands and
executes them as one command.
4 Medalist Family AT Product Manual, Rev. A

1.4 Start/stop time
Within 20 seconds after DC power is applied, the drive is ready. Within
15 seconds after DC power is removed,the drivespindle stops rotating.
1.5 Typical power-up and power-down sequence
The typical power-up and power-down sequences assistyou in evaluat-
ing the drive’s performance; they are not performance specifications.
1.5.1 Power-up sequence
1. Power is applied to the drive.
2. When poweris applied,the LED is on for about 1 second.
3. The spindle motor reaches operating speed in about 4 seconds.
4. The magnetic actuator-lock releases the actuator.
5. The drive achieves final speed-control lock.
6. The heads are positioned over track 0 and the drive is ready.
1.5.2 Power-down sequence
Caution. Donot move the drive untilthe motor hascome to a complete
stop.
1. The poweris turned off.
2. Within 3 seconds, the motor beginsto spin down.
3. The read/write heads automatically move to the shipping zone,which
is inside the maximum data cylinder.
4. The magnetic actuator-lock locks the arm. This completesthe power-
down sequence.
1.5.3 Auto-park
Upon power-down, the read/write heads automatically move to the
shipping zone. The heads park inside the maximum data cylinder and
the magnetic actuator-lock engages.When power is applied, the heads
recalibrate to track 0.
Medalist Family AT Product Manual, Rev. A 5

1.6 Reliability
Readerrorratesaremeasuredwithautomaticretriesanddatacorrection
with ECC enabled and all flaws re-allocated. The mean time between
failures (MTBF) is measured at nominal power at sea level and an
ambient temperature of 40°C.
Nonrecoverable read errors 1 per 1013 bits transferred
Seek errors 1 per 107physical seeks
Contact Start/Stop 40,000 cycles
MTBF 300,000 power-on hours
Service life 5 years
1.7 Physical dimensions
The mounting dimensions are shown in Figure 5 on page 22.
Height, max 1.00 inch (25.4 mm)
Width, max 4.02 inches(102.1 mm)
Depth, max 5.77 inches (146.6 mm)
Weight 1.5 lb (0.68 Kg)
1.8 Environmental specifications
1.8.1 Ambient temperature
Operating 5°C to 55°C (41°F to 131°F)
Nonoperating –40°C to 70°C (–40°F to 158°F)
1.8.2 Temperature gradient
Operating 20°C per hour (36°F per hour)
Nonoperating 30°C per hour (54°F per hour)
6 Medalist Family AT Product Manual, Rev. A

1.8.3 Altitude
Operating –1,000 ft to 10,000 ft (–305 m to 3,048 m)
Nonoperating –1,000 ft to 40,000 ft (–305 m to 12,192 m)
1.8.4 Relative humidity
Operating 8% to 80%noncondensing
Maximum wet bulb 26°C (79°F)
Maximum operating
gradient 10% per hour
Nonoperating 5% to 95%noncondensing
Maximum wet bulb 26°C (79°F)
1.9 Acoustics
Sound pressure is measured from 1 meter above the drive top cover at
idle.
Value Idle Seek
Sound pressure, typ (dBA) 30 36
Sound pressure, max (dBA) 33 39
1.10 Shock and vibration
All shock and vibration specifications assume that the drive is mounted
as recommended in Section 2.6, with the input levels measured at the
drive mounting screws.Shock measurements are basedon an 11msec,
half sine wave shock pulse, not to be repeated more than twice per
second.
During normal operating shock and vibration, there is no physical dam-
age to the driveor performance degradation.Duringnonoperatingshock
and vibration, the read/write heads are positioned in the shipping zone.
Medalist Family AT Product Manual, Rev. A 7

During abnormal operating shock and vibration, there is no physical
damageto the drive, althoughperformance maybe degradedduringthe
shockorvibrationepisode.Whennormaloperatingshocklevelsresume,
the drive meets its performance specifications.
Operating Abnormal Nonoperating
Shock 2 Gs 10 Gs 75 Gs
5–22 Hz vibration 0.020-inch
displacement 0.030-inch displacement 0.160-inch displacement
22–400 Hz vibration 0.50 Gs 0.75 Gs 4.00 Gs
1.11 DC Power
Except duringthe write procedure,you can turn off and turn on power to
the drive in any sequence without losing data or damaging the drive. If
you turn off the power duringthe write procedure,you may lose the data
currently being written.
1.11.1 Input noise
+5V +12V
Voltage tolerance
(including noise) ±5% ±5%
Input noise frequency
(max) 25 MHz 25 MHz
Input noise
(max, peak-to-peak) 100 mV 240 mV
1.11.2 Power management
This drive provides and uses power-management modes to reduce its
overall power consumption. The level of drive activity for each power-
management mode is described below.
You can customize the power-management modes using the AT inter-
face commands that control the power modes. These commands are
described in the
Seagate ATA Interface Reference Manual , publication
number 36111-
xxx .
8 Medalist Family AT Product Manual, Rev. A

1.11.3 Idle and Standby modes
The drive may enter Idle mode or Standby mode through either of the
following actions:
•The computer can send one of the Idle commands or the Standby
commands. All of the commands that put the drive into the Idle or
Standby mode are listed in the
Seagate ATA Interface Reference
Manual.
•The idle timer or the standby timer counts down to zero.
At power-on, the drive sets the idle timer to enter the Idle mode after
25 seconds of inactivity and the standby timer is disabled. On some
computers, the systemsetup utility provides a meansof setting thetimer
delay values. During each read, write or seek, the drive reinitializes the
idle timer and begins counting down from the specified delay to zero.
If the idle timer reaches zero before the drive is commanded to read,
write or seek, the drive switches to the Idle mode. Then, if the standby
timer is enabled, the standby timer begins counting down. After the
standbytimer has finishedcountingdown,the drive switches to Standby
mode. To set the idle and standby timers, refer to the Idle command in
the
Seagate ATA Interface Reference Manual , publication number
36111-
xxx .
InboththeIdleandStandbymodes,thedriveacceptsallcommandsand
returns to the Seeking or Read/write modes any time disc access is
necessary.
1.11.4 Power-management modes
The following power-management modes are supported by the drive:
•Spinup. The drive bringsthespindleanddiscs upto operating speed.
Power in this mode is defined as the average power during the first
10 seconds after starting spinup. The drive enters this mode during
startup and from the Standby mode.
•Seeking. The drive moves the read/write heads to a specificlocation
on the disc surface in preparation for reading or writing the disc.
Read/write electronics are powered down and servo electronics are
active. The power measure during this mode is the average power
while executing random seeks with a 2-revolution (26.6 msec) dwell
between Seek commands.
•Read/write. The drive reads from or writes to the disc. Read/write
electronics are active and the servo is on track. The drive enters this
mode from the Idle mode.
Medalist Family AT Product Manual, Rev. A 9

•Idle. The heads are parked in the shipping zone. The spindle is
spinning, the cache buffer remains enabled and the drive accepts all
commands and returns to the Seeking or Read/write modes when it
receives a command that requires disc access.
•Standby. The spindle is stopped,theheadsare parked in the landing
zone, the actuator is latched and some of the drive electronics are
powered down. The drive reports to the computer that it is ready to
access the disc. When the drive receives a command that does not
require disc access, the drive remains in the Standby mode. When
the drive receives a command that requires disc access, it spins up
and performs the command.
1.11.5 Power consumption
Inthetablebelow,thevaluesapplyatthedrivepowerconnector.Current
was measured with an RMS DC ammeter.
Spinup Seeking Read/ write Idle Standby
Current at +12V
Amps peak 1.9 — — — —
RMS amps typ — 0.398 0.185 0.118 0.012
Watts typ — 4.77 2.22 1.41 0.144
Current at +5V
RMS amps typ — 0.360 0.404 0.225 0.164
Watts typ — 1.80 2.02 1.12 0.82
Power
Total watts typ 7.00 6.60 4.50 2.75 1.0
10 Medalist Family AT Product Manual, Rev. A

The startup current profile of each drive is unique. A typical startup
current profile is shown in Figure 1.
T1 Power is applied to the drive.
T2 After a delay, the startup current is applied and the spindle
begins to turn.
T3 The accelerating current is applied, causing the spindle speed to
increase.
T4 The spindle speed is close to the final correct value. The drive
begins to lock in speed-control circuits.
T5 The magnetic arm-lock releases the arm.
T6 The final speed-control lock is achieved.
T7 The heads are positioned over track 0, and the driveis ready.
1.12 Agency listings
This drive is listed by agenciesas follows:
•Recognized in accordance with UL478 and UL1950
•Certified to CSA C22.2 No. 220-M1986 andCSA C22.2 No. 950
•Certified to VDE 0805/05.90 and EN 60950/1.88 as tested by VDE
0
01
T1
T2
T3
T4 T5
T6
T7
23456789
Amps
Seconds
2.0
1.0
Figure 1. Typical startup current profile
Medalist Family AT Product Manual, Rev. A 11

1.13 FCC verification
ST31220 family AT interface drives are intended to be contained solely
within a personal computer or similar enclosure (not attached to an
external device). As such, a drive is considered to be a subassembly
evenwhenindividually marketedto the customer. As a subassembly, no
Federal Communications Commission authorization, verification or cer-
tification of the device is required.
Seagate Technology, Inc. has tested these drives in an enclosure as
described above to ensure thatthe totalassembly (enclosure,disc drive,
motherboard, power supply, etc.) does comply with the limits for a
Class B computing device, pursuant to Subpart J of Part 15 of the FCC
rules. Operation with noncertified assemblies islikely to resultin interfer-
ence to radio andtelevision reception.
Radioandtelevision interference. Thisequipmentgeneratesanduses
radiofrequencyenergyand, if notinstalledandused in strictaccordance
withthemanufacturer’sinstructions,maycauseinterferencetoradioand
television reception.
This equipment is designed to provide reasonable protection against
such interference in a residential installation. However, there is no
guarantee thatinterferencewillnotoccurinaparticularinstallation.Ifthis
equipment does cause interference to radio or television, which can be
determined by turning the equipment on and off, you are encouraged to
try one or more of the following corrective measures:
•Reorient the receiving antenna.
•Move the deviceto one side or the other of the radio orTV.
•Move the devicefarther away from the radio or TV.
•Plug the equipment into a different outlet so that the receiver and
computer are on different branch outlets.
12 Medalist Family AT Product Manual, Rev. A