
P R O D R I V E   4 2 5   A T    QUANTUM
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/HH               Cylinders    1520| 1021|     |
Capacity form/unform   426/      MB        Heads           9|   16|     |
Seek time   / track  14.0/ 4.0 ms          Sector/track   44|   51|     |
Controller           IDE / AT              Precompensation
Cache/Buffer           256 KB LOOK-AHEAD   Landing Zone
Data transfer rate    1.530 MB/S int       Bytes/Sector      512
                      4.000 MB/S ext
Recording method     RLL 1/7                        operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C         4 55    |    -40 60
Power: sleep              W     Humidity     %         8 85    |      5 95
       standby            W     Altitude    km    -0.061  3.000| -0.061 12.000
       idle          11.4 W     Shock        g        10       |     60
       seek          12.8 W     Rotation   RPM      3606
       read/write         W     Acoustic   dBA        45
       spin-up            W     ECC        Bit   48,WITH 11BIT BURST COR
                                MTBF         h     150000
                                Warranty Month        12
Lift/Lock/Park     YES          Certificates     CSA,FCC,SDA,TUV,UL478,VDE    

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                        L   A   Y   O   U   T
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QUANTUM  PRODRIVE 425AT  PRODUCT MANUAL 81-100810-01, 10/1991

  +---------------------------------------------------------+
  |                                    ***      ***         |XX
  |                                    ***      ***         |XX
  |                                      IID  TM SP DS      |XX 40-pin
  |                                                         |XX J1
  |                                                         |XX
  |                                                         |XX
  |                                                         |.X
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
 ++                                                         |
 ++                                                         |XX Power
  |                                                         |XX J3
  +---------------------------------------------------------+



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                      J   U   M   P   E   R   S
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QUANTUM  PRODRIVE 425AT  PRODUCT MANUAL 81-100810-01, 10/1991

 Jumper Setting
 ==============

 x = Jumpers set at factory


 DS  Drive Select Jumper Option
 ------------------------------
 x   CLOSED  Single drive or MASTER (Drive 0)
     OPEN    SLAVE (Drive 1)

 Note: The order in which drives are connected in a daisy chain has no
       significance.

 You can daisy-chain two drives on the AT-bus interface. When daisy-
 chaining two drives, configure one drive as the MASTER, the other as
 the SLAVE, with the Drive Select (DS) jumper pins on the drives.

 Or use the IID jumper to select Master/Slave via the drive interface
 cable.


 SP  Slave Present Jumper Option
 -------------------------------
 In combination with the current DS jumper setting, the Slave Present
 (SP) jumper implements one of two possible configurations.

  - If the drive is configured as a Master - that is, with the DS
    jumper installed - the SP jumper indicates to the drive that a
    Slave drive is present. The SP jumper should be installed on the
    Master if the Slave drive does not use the Drive/Active Slave
    Present signal (pin 39) to indicate its presense.

  - When the drive is configured as a SLAVE - that is with DS jumper
    not installed - and the MASTER is a non-Quantum drive, a jumper
    installed on the SP jumper pins puts the ProDrive into a special
    slave mode. In this mode, the ProDrive does not do hardware tests
    in the diagnostics command to avoid taking too long to drive BUSY,
    resulting in making the operation with another drive as fast as
    possible.

 Quantum ships all ProDrive 425AT hard disk drives without a jumper
 installed on the SP jumper pins.


 TM  Drive Mode Jumper Option
 ----------------------------
 The drive mode jumper options maintains compatibility with the
 ProDrive 40/80 AT hard disk drives. When a jumper is installed on the
 TM jumper pins, the ProDrive 425AT hard disk drive is in a ProDrive
 40/80AT compatible mode as a master or as a slave depending on the
 way the DS(IID) and SP jumpers are installed.


 Drive Mode Jumper Options
 -------------------------
  +------+------+------+------+--------------------------------------+
  |CONFIG|DS/IID| SP   |  TM  | Description                          |
  +------+------+------+------+--------------------------------------+
  |   1  |OPEN  |OPEN  |OPEN  | SLAVE when the Master is a Quantum   |
  |      |      |      |      | ProDrive other than the 40/80AT.     |
  +------+------+------+------+--------------------------------------+
  |   2  |OPEN  |OPEN  |CLOSED| SLAVE in ProDrive 40/80AT mode       |
  +------+------+------+------+--------------------------------------+
  |   3  |OPEN  |CLOSED|OPEN  | SLAVE when the Master is a non-      |
  |      |      |      |      | Quantum drive                        |
  +------+------+------+------+--------------------------------------+
  |   4  |OPEN  |CLOSED|CLOSED| NOT USED!                            |
  +------+------+------+------+--------------------------------------+
  |   5  |CLOSED|OPEN  |OPEN  | MASTER drive PDIAG mode checking     |
  |      |      |      |      | DASP for slave                       |
  +------+------+------+------+--------------------------------------+
  |   6  |CLOSED|OPEN  |CLOSED| MASTER drive in ProDrive 40/80AT     |
  |      |      |      |      | mode checking DASP for slave         |
  +------+------+------+------+--------------------------------------+
  |   7  |CLOSED|CLOSED|OPEN  | MASTER in PDIAG mode using the SP    |
  |      |      |      |      | jumper to determine if a slave       |
  |      |      |      |      | is present                           |
  +------+------+------+------+--------------------------------------+
  |   8  |CLOSED|CLOSED|CLOSED| MASTER in ProDrive 40/80AT mode      |
  |      |      |      |      | using the SP jumper to determine     |
  |      |      |      |      | if a slave is present                |
  +------+------+------+------+--------------------------------------+
 IID provides an alternative method for DS (Drive Select).

 The ProDrive 40/80AT hard disk drive mode always means that the drive
 select bit in the AT interface chip is not reset to zero on
 diagnostics commands or soft resets, and that the drives do not check
 for PDIAG.

 Description of Configurations (from Table)

 1. ProDrive slave in the standard CAM spec mode.

 2. ProDrive slave with a ProDrive 40/80AT hard disk drive master.

 3. A ProDrive is a slave, however, daisy-chained to a non-Quantum
    drive, which does not apply the CAM ATA protocol for DASP. In this
    mode, the ProDrive 425AT hard disk drive does not do hardware
    tests in the diagnostic command to avoid taking too long to drop
    BUSY. This makes operation with another drive as fast as possible.

 5. ProDrive master in the standard Command Access Method (CAM) ATA
    specification mode. ProDrive master used DASP to check for slave
    and uses PDIAG to determine if the slave passed power on, soft
    reset, and diagnostics. This is the factory default setting.

 6. ProDrive master in ProDrive 40/80AT hard disk drive mode. The
    code looks at DASP to determine if a slave is present. If it sees
    DASP, it assumes the other drive is a ProDrive 40/80AT hard disk
    drive and operates in the ProDrive 40/80AT hard disk drive mode.

 7. A ProDrive master with a non-Quantum slave, which does not apply
    the CAM ATA protocol for DASP. The drive knows there is a slave
    by the SP jumper, and it does not check DASP. It does check PDIAG
    at power on, soft reset, and diagnostics. On the diagnostics
    command, the ProDrive skips the hardware tests, making operation
    another drive as fast as possible.

 8. A ProDrive master with a ProDrive 40/80AT hard disk drive slave.
    The code knows a slave is present, by the SP jumper, and does not
    check DASP.



 J3   DC Power and pin connector assignments
 -------------------------------------------
      +------------+   pin 1    +12 VDC
      | 4  3  2  1 |   pin 2    +12 Volts Return (Ground)
      +------------+   pin 3    + 5 Volts Return (Ground)
                       pin 4    + 5 VDC

 Note: Pins 2 and 3 are connected on the drive.



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QUANTUM  PRODRIVE 425AT  PRODUCT MANUAL 81-100810-01 10/1991

 Notes on Installation
 =====================

 Mounting
 --------
 The ProDrive 425AT hard disk drive can be mounted in any orientation.
 UNC 6-32 screws are recommended for mounting.

 Note: With the exception of the faceplate and mounting brackets,
 clearence between the drive and any other surface must be a minimum
 of 0.10 inch.

 Caution: The printed circuit board (PCB) is very close to the
 mounting holes on the drive. Do not exceed the specified length for
 the mounting screws. The specified screw length allows full use of
 the mounting-hole threads, while avoiding damaging or placing
 unwanted stress on the PCB. To avoid stripping the mounting-hole
 threads, the maximum torque applied to the mounting screws must not
 exceed 8 inch-pounds.


 Ventilation
 -----------
 The ProDrive 425AT hard disk drive operates without a cooling fan,
 provided the ambient air temperature does not exceed 122*F (50*C).
 Any user-designed cabinet should provide adequate air circulation to
 prevent the maximum temperature from beeing exceeded.


 AT-Bus Interface Connector J1
 -----------------------------
 The ProDrive 425AT hard disk drive requires one AT-bus
 interface cable connector.

 The AT-bus interface cable connector (J1) on the drive is a 40-pin
 Universal Header connector. Pin 20 has been removed to prevent in-
 correct installation of the mating connector. The mating connector
 must have a keying plug installed in pin position 20.

 Note: To avoid plugging the connector backwards, unkeyed mating
 connections should not be used.

 Recommended part numbers for the mating connector:

 40-pin connector, without strain relief  AMP P/N 1-746185-0, or
                                          equivalent

 Strain relief for 40-pin connector       AMP P/N 1-499252-1, or
                                          equivalent

 Keying Plug                              AMP P/N 86286-1, or
                                          equivalent


 DC Power Connector J3
 ---------------------
 The DC power connector is a 4-pin Molex connector (P/N 8981-4SM3 or
 equivalent) mounted on the back edge of the Printed Circuit Board
 (PCB).

 Recommended connectors and their part numbers are:

  4-pin connector       AMP P/N 1-480424-0 or equivalent

  Loose-piece contacts  AMP P/N 60619-4 or equivalent

  Strip contacts        AMP P/N 61117-4 or equivalent


 Faceplate LED Operation
 -----------------------
 Whenever the drive initiates the execution of a command, a green LED
 on the faceplate ligths, and remains lit until the execution of the
 command is complete or aborted.


 Air Filtration
 --------------
 ProDrive Series hard drives are Winchester-type drives. The heads fly
 very close to the media surface, with a nominal flying height of six
 microinches. Therefore, it is essential that the air circulating
 within the drive be kept free of particles. Quantum assembles the
 drive in a Class-100, purified air environment, then seals the drive
 with a metal cover. When the drive is use, the rotation of the disks
 forces the air inside the drive through an internal filter.


 Disk Format
 -----------
 The drive have eight zones, with 44 to 78 sectors per track,
 depending on the location of the zone on the disk. Two sectors per
 cylinder are reserved as spares for defect mangement. Thus, the
 number of sectors per cylinder ranges from 700 in the outermost zone
 to 394 in the inner zone for the ProDrive 425AT hard disk drive.


 Electrical Characteristics
 --------------------------
 All signals are TTL-compatible - with logic one greater than 2.0
 volts and less than 5.25 volts; and logic zero, greater than 0.0
 volts and less than 0.7 volts. Neither the adapter board nor the
 drives requires terminating resistors.


 AT-BUS Interface
 ----------------
 The ProDrive 425AT hard disk drive uses the standard IBM PC AT-bus
 interface, and is available with or without an adapter board. With
 the adapter board, a ProDrive 425AT hard disk drive can plug directly
 into a 16-bit expansion slot on an AT-compatible computer. Without
 the adapter board, the drive is compatible with other AT-bus
 architectures, and can be plugged into an embedded AT adapter or
 existing adapter board.


 Adapter Board
 -------------
 The adapter board provides an IBM PC-AT I/O-bus interface. The AT-bus
 interface signals D8-D15, INTRQ and IOCS16-require an I/O extended
 bus connector. The adapter board buffers data and control signals
 between the drive and the host system, and decodes addresses on the
 host address bus. The Command Block Registers on the drive - accept
 commands from the host system BIOS.

 NOTE
 Some host systems do not read the Status Register after the drive
 issues an interrupt. In such cases, the interrupt may not be
 acknowledged. To overcome this problem, a jumper option on the
 adapter board allows interrupts to be controlled by the drive's
 interrupt logic.



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                      F   E   A   T   U   R   E  S
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QUANTUM  PRODRIVE 425AT  PRODUCT MANUAL 81-100810-01 OCTOBER 1991

 General Description
 -------------------
 The Quantum ProDrive Series is a broad family of high-performance,
 3 1/2-inch form factor hard drives manufactured to meet the highest
 product-quality standards. These drives use nonremovable rigid disks
 as their storage media, have formatted capacities that range from
 40 to 426 megabytes, and are available with various interfaces.


 Seek Times/Miscellaneous Times:
 ------------------------------

 Times                  | Typical   | Maximum   | Maximum    |
 msec.                  | Nominal   | Nominal   | Worst-Case |
                        | Condition | Condition | Condition  |
 -----------------------+-----------+-----------+------------+
 Single Track Seek      |    4      |     5     |     5      |
 Average Seek           |    14     |     15.5  |     16.5   |
 Third-Stroke Seek      |    15     |     16.5  |     17.5   |
 Full-Stroke Seek       |    27     |     30    |     33     |
 Average Rotational     |           |           |            |
 Latency                |    8.3    |     -     |     -      |
 Sequential Head Switch |    2.2    |     -     |     -      |
 Power-Up Time          |    -      |     -     |     20     |
 -----------------------+-----------+-----------+------------+

 Seek time is the time required for the actuator to seek and settle on
 track. Quoted seek times include head settling time, but not command
 overhead or rotational latency time.

 Seek time is measured by averaging 1000 seeks of the indicated
 length. Average seek time is the average time of 1000 random seeks.
 When a seek error occurs, recovery for that seek may take up to two
 seconds.


 Preventive Maintenance
 ----------------------
 The ProDrive 425AT hard disk drive requires no preventive
 maintenance.


 Defect Detection
 ----------------
 At sector level, any discrepancy between recorded data and recovered
 data constitutes a data error. In high-density digital recording
 systems, it is necessary to use an error-detection and correction
 scheme to enhance the performance and increase the reliability of the
 system.

 Data errors are either soft - correctable on retries and not readily
 repeatable - or hard - repeatable with high probability. The
 signal-to-noise ratio of the system affects the occurrence of soft
 errors, which represent marginal conditions of the media, heads,
 read/write circuitry. Hard errors occur due to defects, pits,
 scratches, or thin spots in the media. The drive can skip, or not
 use, defective sectors on the media for storage.


 Factory-Found Defects
 ---------------------
 At the factory, Quantum scans the disks for defective sectors and
 deallocates sectors containing defects prior to shipment. The drive
 records a primary defect list that contains the locations of all
 factory-found defective sectors in a reserved cylinder on the disk.
 The defects are spared inline. In-line sparing skips each factory-
 found defect and shifts subsequent sectors on the track to
 sequential sectors. Two sectors at the end of each cylinder are
 spares, or replacement sectors. The drive allocates spare sectors as
 required to maintain the proper number of blocks per cylinder.


 Automatic Actuator Lock
 -----------------------
 To ensure data integrity and prevent damage during shipment, all
 ProDrive Series hard disk drives feature a dedicated landing zone and
 Quantum's patented AIRLOCK. AIRLOCK, locks the headstack in the
 landing zone. It consists of an airvane mounted near the perimeter of
 the disk stack and a locking arm that restrains the actuator arm
 assembly when the disks are not rotating.

 When DC power is applied to the motor and the disk stack rotates, the
 rotation generates an airflow on the surface of the disk. As the flow
 of air across the airvane increases with disk ratation, the locking
 arm pivots away from the actuator arm, enabling the headstack to move
 out of the landing zone. When DC power is removed from the motor, a
 return mechanism automatically pulls the actuator into the landing
 zone, where the AIRLOCK holds it in place.


 Media Quality
 -------------
 The ProDrive 425AT hard disk drive features automatic defect
 management, making the manual identification of defects unneccessary.
 Defect management is completely transparent to the user.


 Error Rates
 -----------
 A data error occurs whenever the drive fails to read or write a
 sector of data correctly. An error detected when reading may be
 correctable or uncorrectable. When a data error occurs, if the data
 can be transferred successfully using the drive's default error-
 recovery algorithm, the data error is recoverable; otherwise, it is
 unrecoverable. The miscorrection rate indicate the frequency with
 which the drive transfers incorrect read data, due to faulty ECC
 correction using the default error-recovery algoritm.

 If a data error recurs on each of eight retries, it is a read error;
 otherwise it is a soft error. Hard errors generally occur due to
 media defects.


 DisCache
 --------
 Quantum's proprietary, look-ahead, caching scheme - provides faster
 access to data on the disk by anticipating host-system requests for
 data. DisCache prefetches data into a three segment cache in high-
 speed RAM (Random-Access Memory). When the host requests data pre-
 fetched to the cache, the drive accesses the cache, rather than the
 disk. The ProDrive 425S hard disk drive uses an advanced continuous-
 prefetch algorithm. When the drive receives a READ command that re-
 quests data currently in the cache, it continues to prefetch data.


