
M A B - 3 0 4 5 F C               A L 4    FUJITSU
                                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/SLIMLINE         Cylinders    8491|     |     |
Capacity form/unform  4550/ 5950 MB        Heads           5|     |     |
Seek time   / track   8.0/ 1.0 ms          Sector/track     |     |     |
Controller           SCSI3 SCA/FIBRE-CHAN  Precompensation
Cache/Buffer          4000 KB FIFO BUFFER  Landing Zone
Data transfer rate   19.500 MB/S int       Bytes/Sector      512
                    106.250 MB/S ext FIBRE
Recording method     PR4ML                          operating  | non-operating
                                                  -------------+--------------
Supply voltage     5 V          Temperature *C         5 50    |    -10 60
Power: sleep              W     Humidity     %        20 80    |     20 80
       standby            W     Altitude    km            3.000|        12.000
       idle               W     Shock        g         5       |     60
       seek               W     Rotation   RPM      7200
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit   ON THE FLY,REED SOLOMON
                                MTBF         h    1000000
                                Warranty Month
Lift/Lock/Park     YES          Certificates                                  

**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
FUJITSU  MAA SERIES FIBRE CHANNEL  OPERATING MANUAL

 Notes On Installation
 ---------------------

 Installation direction
 ----------------------

     horizontally                           vertically
   +-----------------+             +--+                       +--+
   |                 |             |  +-----+           +-----+  |
   |                 |             |  |     |           |     |  |
 +-+-----------------+-+           |  |     |           |     |  |
 +---------------------+           |  |     |           |     |  |
                                   |  |     |           |     |  |
                                   |  |     |           |     |  |
 +---------------------+           |  +-----+           +-----+  |
 +-+-----------------+-+           +--+                       +--+
   |                 |
   |                 |
   +-----------------+


 Mounting frame structure
 ------------------------
 To guarantee integrity of the IDD disk enclosure (DE) insulation once
 mounted on the frame inside the system, special attention must be
 given to the note below.

 Note: Generally, SG and FG are connected at one point in the system
 enclosure. Therefore, use following procedure to maintain the
 insulation when mounting the IDD.

 Use the frame with an embossed structure or the like to avoid contact
 between the DE base and FG. Mount the IDD with making a gap of 2.5 mm
 or more between the IDD and the frame of the system.

 The inward projection of the screw from the DE base wall at the
 corner must be 4 mm or less.

 Tightening torque of screw must be secured with 6kg-cm.
 Damage: To absolutely guarantee integrity of the IDD disk enclosure
 (DE) insulation once actually mounted to the frame inside the system,
 special attention must be given to the cautionary notes below.

 Mount the disk enclosure using a frame of the embossed structure
 or a similar structure providing an equivalent function and making
 sure there is a distance of at least 2.5 mm between this frame and
 the frame on the system side.

 The length of the portion of the mounting screw coming out of the
 external wall end of the mounting frame or the IDD tap surface
 (penetration depth) should be 4 mm or less.


 Limitation of side-mounting
 ---------------------------
 Mount the side using the screw holes at both the ends. Do not use the
 center hole.


 Interface connector
 -------------------
 The connector for the fiber channel loop bus is an unshielded SCA-2
 connector conforming to SCSI-3 type which has two 20-pin rows spaced
 1.27 mm (0.05 inch) apart.


 Installation
 ------------
 When mounting/dismounting the drive, make sure the vibration and
 shock requirements are met.

 When removing the spindle motor from the system without stopping it
 while power is on, pay special attention to shock in particular until
 the disk drive completely stops running (about 30 seconds).


 Mounting procedures
 -------------------
 Since mounting the drive depends on the system cabinet structure,
 determine the work procedures considering the requirements specific
 to each system.

 Fix the drive in the system cabinet with four mounting screws as
 follows:

 - The drive has 8 mounting holes (both sides: 2   2, bottom: 4). Fix
   the drive by using four mounting holes of both sides or the bottom.

 - Use mounting screws whose lengths inside the drive mounting frame
   are 4 mm or less when the screws are tightened.

 - When mounting the drive, be careful not to damage parts on the
   PCAs.

 Check that the DE (signal ground) does not touch the system cabinet
 chassis (frame ground). There must be a 2.5 mm or more space between
 the DE and chassis.


 IMPORTANT
 ---------
 The LED lights during the IDD is executing a command. However, in
 same commands, the lighting time is only an instant. Therefore, it
 seems that the LED blinks or the LED remains off.


 Checking connection
 -------------------
 When the initial operation is checked normally after power is turned
 on, check that the IDD is connected to the loop from the host system.
 Although checking the connection depends on the structure of the host
 system, this section describes the general procedures.


 Dismounting Drive
 -----------------
 Since the method and procedure for dismounting the disk drive for
 replacement of the drive, etc. depends on the locker structure of the
 system, etc., the work procedure must be determined in consideration
 of the requirements specific to the system. This section describes
 the general procedure and notes on dismounting the drive.


 CAUTION
 1. When dismounting the drive which is mounted on the system while
    power is supplied to it.
    The drive to be dismounted must be separated from the loop.
    Dismounting the drive which is not separated from the loop may
    cause an unexpected error.

    If the drive is not separated from the loop, issue an LPB to the
    drive from the initiator in a primitive sequence of the order set.
    It is recommended to stop the spindle motor prior to this loop
    separation operation. The spindle motor can be stopped by a
    START/STOP command. It takes about 30 seconds for the spindle
    motor to stop completely.

    Then, dismount the drive using the drive mounting/dismounting
    mechanism, etc. of the system. If the drive is dismounted while
    the spindle motor is running, special care is required to avoid
    excessive vibration or shock to the drive. It is recommended to
    stop the operation once the SCA connector breaks off contact and
    wait until the spindle motor stops (about 30 seconds) before
    dismount the drive.

    When storing or transporting the drive, put it in an antistatic
    bag.

 2. When dismounting the drive which is mounted on the system while
    power is not supplied to it.

    Do not move the drive until the drive stops completely (about 30
    seconds if the spindle motor was stopped by a START/STOP UNIT
    command, and about 30 seconds after powering-off when the
    power was simply turned off).

    Then, dismount the drive using the drive mounting/dismounting
    mechanism, etc. of the system.
    When storing or transporting the drive, put it in an antistatic
    bag.


 4MB programmable multi-segment data buffer
 ------------------------------------------
 Data is transferred between fiber-channel loop and disk media through
 the embedded 4MB data buffer in the IDD. This buffer can be divided
 into maximum 16 areas. This feature provides the suitable usage
 environment for users.

 Since the initiator can control the disconnect/reconnect timing on
 the fiber-channel loop by specifying the condition of stored data to
 the data buffer or empty condition of the data buffer, the initiator
 can perform the effective input/output operations with utilizing high
 data transfer capability of the fiber-channel regardless of actual
 data transfer rate of the disk drive.


 Read-ahead cache feature
 ------------------------
 After executing the READ command, the IDD reads automatically and
 stores (prefetches) the subsequent data blocks into the data buffer
 (Read-ahead caching).

 The high speed sequential data access can be achieved by transferring
 the data from the data buffer without reaccessing the disk in case
 the subsequent command requests the prefetched data blocks.


 Disks
 -----
 The disks have an outer diameter of 95 mm (3.74 inch) and inner
 diameter of 25 mm (0.98 inch). The disks are good for at least 10,000
 contact starts and stops. Each model contains following number of
 disks.

 MAA3182:10
 MAB3091/MAC3019:5
 MAB3045/MAC3045:3


 Heads
 -----
 The MR (Magnet - Resistive) of the CSS (contact start/stop) type
 heads are in contact with the disks when the disks are not rotating,
 and automatically float when the rotation is started.


 Spindle motor
 -------------
 The disks are rotated by a direct-drive hall-less DC motor. The motor
 speed is controlled by a feedback circuit using the counter
 electromotive current to precisely maintain the speed at  0.5% of the
 specified speed.


 Actuator
 --------
 The actuator, which uses a rotary voice coil motor (VCM), consumes
 little power and generates little heat. The head assembly at the end
 of the actuator arm is controlled and positioned via feedback of
 servo information in the data.

 The actuator positions heads on the CCS zone over the disk and is
 locked by the mechanical lock when the power is off or the spindle
 motor is stopped.


 Air circulation (recirculation filter, breather filter)
 -------------------------------------------------------
 The heads, disks, and actuator are hermetically sealed inside a disk
 enclosure (DE) to keep out dust and other pollutants. The DE has a
 closed-loop air recirculation system. Using the movement of the
 rotating disks, air is continuously cycled through a filter. This
 filter will trap any dust generated inside the enclosure and keep the
 air inside the DE contaminant free. To prevent negative pressure in
 the vicinity of the spindle when the disks begin rotating, a
 breather filter is attached. The breather filter also equalizes the
 internal air pressure with the atmospheric pressure due to
 surrounding temperature changes.


 Read/write circuit
 -------------------
 The read/write circuit uses head LSI chips and partial response class
 4 maximum likelihood (PR4ML) modulator and demodulator circuit to
 prevent errors caused by external noise, thus improving data
 reliability.


 Controller circuit
 ------------------
 The controller circuit uses LSIs to increase the reliability and uses
 a high speed microprocessing unit (MPU) to increase the performance
 of the SCSI controller.

 The mode of connection of all devices to the fiber channel is called
 "node."  Each node has at least one port called "N-port." In the
 FC-AL, a port is particularly called "node loop (NL) port." The
 MAAxxxxFC, MABxxxxFC and MACxxxxFC have two ports; one is connected
 to one FC-AL and a maximum of 126 NL ports can be connected to one
 loop.


 Loop configuration
 ------------------
 One port incorporates a transmit circuit and receive circuit.
 Information is transmitted/received by differential signals via
 electric signal lines. This pair of signal lines is called a link.
 Since signals on a link are transmitted in one direction, wiring must
 be conducted so that it may form a loop connection on the system.
 In the case of the FC-AL interface, information is ansmitted/received
 via each node connected on a loop. Accordingly, if the power supply
 is off at a node connected to the loop or if interface signals cannot
 be transmitted/received normally, the loop will no longer function.
 To avoid such a nonconformity, a circuit called "port bypass circuit"
 is generally provided on the back plane of the system.


 Node addressing
 ---------------
 Each node on the fiber channel loop is assigned its specific model
 number (SEL ID). The SEL ID of the drive is set at the signal level
 on the back plane through 7 signals from SEL_0 to SEL_6 of the SCA
 interface connector (CN1). In signal bit weighting, SEL_6 is the MSB
 indicating 2 6 and SEL_0 is the LSB indicating 2 0.



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                      F   E   A   T   U   R   E  S
**********************************************************************
FUJITSU  MAA FIBRE CHANNEL  OPERATING MANUAL

 Damage
 ------
 When mounted in the system, the disk enclosure (DE) of the IDD
 requires observation of the following mounting precautions to keep
 the DE isolated from the mounting frame.

 - Mount the disk enclosure using a frame of the embossed structure
   or a similar structure providing an equivalent function and making
   sure there is a distance of at least 2.5 mm between this frame and
   the frame on the system side.

 - The length of the portion of the mounting screw coming out of the
   external wall end of the mounting frame or the IDD tap surface
  (penetration depth) should be 4 mm or less.


 Damage to drive
 ---------------
 The hole and screwed section are for adjustment of the balance of
 pressure inside/outside the DE, and should not be covered with a
 label or seal.

 Seals attached to the DE are used to keep airtightness to prevent
 dust from entering the DE, and should not be peeled off or damaged.


 Data loss
 ---------
 Do not move the drive until the drive stops completely (about 30
 seconds if the spindle motor was stopped by a START/STOP UNIT
 command, and about 30 seconds after powering-off when the power
 was simply turned off).

 Notes:
 When the SEND DIAGNOSTIC command terminates with the CHECK CONDITION
 status, the INIT must collect the error information using the REQUEST
 SENSE command. The RECEIVE DIAGNOSTIC RESULTS command cannot read out
 the error information detected in the self-diagnostics.


 Damage
 ------
 Do not open the DE in the field because it is completely sealed.


 Data loss
 Save data stored on the disk drive before requesting repair. Fujitsu
 does not assume responsibility if data is destroyed during servicing
 or repair. Save data stored on the disk drive before requesting
 repair.

 Fujitsu does not assume responsibility if data is destroyed during
 servicing or repair.

 Since GaAs compound semiconductors are used in this product, it is
 necessary to strictly adhere to the following items to prevent
 danger.

 - Do not take them into the mouth.
   It is dangerous to ingest GaAs compound semiconductors used in
   this product.

 - Do not transform them to gas, powder or liquid.
   It is dangerous to inhale or drink by mistake the liquid generated
   by burning, crushing or chemically processing this product.

 - When disposing of this product, adhere to applicable domestic laws
   and your waste disposal regulations.
   When disposing of this product, separate it from general industrial
   waste and household waste.


 FC-AL standard
 --------------
 The IDD provides not only FC-AL basic functions but also the
 following features:
 - Arbitration
 - Data frame CRC function
 - Command set which meets the logical specification of the SCSI CCS
   (Common Command Set for Direct Access Device) requirements (Rev.
   4.B)

 The SCSI commands can manipulate data through logical block
 addressing regardless of the physical characteristics of the disk
 drive. This allows software to accommodate future expansion of system
 functions.


 Dual port support
 -----------------
 In order to support dual ports, the IDD is equipped with two pairs of
 fiber channel driver/receiver.


 High speed data transfer
 ------------------------
 The data transfer rate on the fiber channel loop is 106.25 MB/s
 maximum. In addition, the large capacity data buffer of the HDD
 allows the user to make full use of the high speed data transfer
 capability of the fiber channel loop.


 High speed spindle motor (MACxxxxFC)
 ------------------------------------
 The MACxxxxFC type IDD increases the number of revolutions of the
 spindle motor from conventional 7,200 rpm to 10,033 rpm. Increasing
 the number of revolutions of the spindle motor will make it possible
 to improve the data transfer rate and reduce the rotation wait time.


 Continuous block processing
 ---------------------------
 The addressing method of data blocks is logical block address. The
 initiator can access data by specifying block number in a logically
 continuous data space without concerning the physical structure of
 the track or cylinder boundaries.

 The continuous processing up to [64K-1] blocks in a command can be
 achieved, and IDD can perform continuous read/write operation when
 processing data blocks on several tracks or cylinder.


 4MB programmable multi-segment data buffer
 ------------------------------------------
 Data is transferred between fiber-channel loop and disk media through
 the embedded 4MB data buffer in the IDD. This buffer can be divided
 into maximum 16 areas. This feature provides the suitable usage
 environment for users.

 Since the initiator can control the disconnect/reconnect timing on
 the fiber-channel loop by specifying the condition of stored data to
 the data buffer or empty condition of the data buffer, the initiator
 can perform the effective input/output operations with utilizing high
 data transfer capability of the fiber-channel regardless of actual
 data transfer rate of the disk drive.


 Read-ahead cache feature
 ------------------------
 After executing the READ command, the IDD reads automatically and
 stores (prefetches) the subsequent data blocks into the data buffer
 (Read-ahead caching). The high speed sequential data access can be
 achieved by transferring the data from the data buffer without
 reaccessing the disk in case the subsequent command requests the
 prefetched data blocks.


 Command queuing feature
 -----------------------
 The IDD can queue maximum 63 commands, and optimizes the issuing
 order of queued commands by the reordering function. This feature
 realizes the high speed processing.


 Reserve and release functions
 -----------------------------
 The IDD can be accessed exclusively in the multi-host or multi-
 initiator environment by using the reserve and release functions.


 Enclosure service function
 --------------------------
 The IDD supports an enclosure service interface (ESI) compliant with
 the SFF-8067. This interface provides the function of setting/reading
 enclosure service information using the SCSI-3 enclosure service
 command set (SES).


 Error recovery
 --------------
 The IDD can try to recover from errors in fiber-channel loop or the
 disk drive using its powerful retry processing. If a recoverable data
 check occurs, error-free data can be transferred to the initiator
 after being corrected in the data buffer. The initiator software is
 released from the complicated error recover processing by these error
 recovery functions of the IDD.


 Automatic alternate block reassignment
 --------------------------------------
 If a defective data block is detected during read, the IDD can
 automatically reassign its alternate data block.


 Programmable data block length
 ------------------------------
 Data can be accessed in fixed-block length units. The data block
 length is programmable, and can at initializing with a multiple of
 four for the 512 to 528 bytes.


 Defective block slipping
 ------------------------
 A logical data block can be reallocated in a physical sequence by
 slipping the defective data block at formatting. This results in high
 speed contiguous data block processing without a revolution delay due
 to defective data block.


 High speed positioning
 ----------------------
 A rotary voice coil motor achieves fast positioning.


 Large capacity
 --------------
 A large capacity can be obtained from 3.5-inch disk drives by
 dividing all cylinders into several partitions and changing the
 recording density on each partition (constant density recording). The
 disk subsystem with large capacity can be constructed in the good
 space efficiency.


 Start/Stop of spindle motor
 ---------------------------
 Using the SCSI command, the host system can start and stop the
 spindle motor.


 Diagnosis
 ---------
 The IDD has a diagnostic capability which checks internal controller
 functions and drive operations to facilitate testing and repair.


 Low power consumption
 ---------------------
 By using highly integrated LSI components, the power consumption of
 the IDD is very low, and this enables the unit to be used in wide
 range of environmental conditions.


 Low noise and low vibration
 ---------------------------
 Approx. 4.2 bels for the IDD. This makes it ideal for office use. The
 IDD has rubber vibration isolators, which minimize the transfer of
 vibration.


 Microcode downloading
 ---------------------
 The IDD implements the microcode download feature. This feature
 achieves easy maintainability of the IDD and function enhancing.


 Spindle motor
 -------------
 The disks are rotated by a direct-drive hall-less DC motor. The motor
 speed is controlled by a feedback circuit using the counter
 electromotive current to precisely maintain the speed at  0.5% of the
 specified speed.


 Actuator
 --------
 The actuator, which uses a rotary voice coil motor (VCM), consumes
 little power and generates little heat. The head assembly at the end
 of the actuator arm is controlled and positioned via feedback of
 servo information in the data.

 The actuator positions heads on the CCS zone over the disk and is
 locked by the mechanical lock when the power is off or the spindle
 motor is stopped.


 Air circulation (recirculation filter, breather filter)
 -------------------------------------------------------
 The heads, disks, and actuator are hermetically sealed inside a disk
 enclosure (DE) to keep out dust and other pollutants. The DE has a
 closed-loop air recirculation system. Using the movement of the
 rotating disks, air is continuously cycled through a filter. This
 filter will trap any dust generated inside the enclosure and keep the
 air inside the DE contaminant free. To prevent negative pressure in
 the vicinity of the spindle when the disks begin rotating, a breather
 filter is attached. The breather filter also equalizes the internal
 air pressure with the atmospheric pressure due to surrounding
 temperature changes.


 Read/write circuit
 ------------------
 The read/write circuit uses head LSI chips and partial response class
 4 maximum likelihood (PR4ML) modulator and demodulator circuit to
 prevent errors caused by external noise, thus improving data
 reliability.


 Controller circuit
 ------------------
 The controller circuit uses LSIs to increase the reliability and uses
 a high speed microprocessing unit (MPU) to increase the performance
 of the SCSI controller.

 The mode of connection of all devices to the fiber channel is called
 "node."  Each node has at least one port called "N-port." In the
 FC-AL, a port is particularly called "node loop (NL) port." The
 MAAxxxxFC, MABxxxxFC and MACxxxxFC have two ports; one is connected
 to one FC-AL and a maximum of 126 NL ports can be connected to one
 loop.


 Loop configuration
 ------------------
 One port incorporates a transmit circuit and receive circuit.

 Information is transmitted/received by differential signals via
 electric signal lines. This pair of signal lines is called a link.
 Since signals on a link are transmitted in one direction, wiring must
 be conducted so that it may form a loop connection on the system.
 In the case of the FC-AL interface, information is transmitted/
 received via each node connected on a loop. Accordingly, if the power
 supply is off at a node connected to the loop or if interface signals
 cannot be transmitted/received normally, the loop will no longer
 function. To avoid such a nonconformity, a circuit called "port
 bypass circuit" is generally provided on the back plane of the
 system.


 Node addressing
 ---------------
 Each node on the fiber channel loop is assigned its specific model
 number (SEL ID). The SEL ID of the drive is set at the signal level
 on the back plane through 7 signals from SEL_0 to SEL_6 of the SCA
 interface connector (CN1). In signal bit weighting, SEL_6 is the MSB
 indicating 2 6 and SEL_0 is the LSB indicating 2 0.

 The SEL ID setting of the drive ranges from #0(x'00') to #125(x'7D').


 Error rate
 ----------
 Errors detected during initialization and replaced by alternate block
 assignments are not included in the error rate. Data blocks to be
 accessed should be distributed over the disk medium equally.


 Unrecoverable error rate
 ------------------------
 Errors which cannot be recovered within 63 retries and ECC correction
 should not exceed 10 per 10 15 bits.


 Positioning error rate
 ----------------------
 Positioning errors which can be recovered by one retry should be 10
 or less per 10 8 seeks.


 Mean Time To Repair (MTTR)
 --------------------------
 MTTR is the average time taken by a well-trained service mechanic to
 diagnose and repair a drive malfunction. The drive is designed for a
 MTTR of 30 minutes or less.


 Service life
 ------------
 The service life under suitable conditions and treatment is as
 follows.

 The service life is depending on the environment temperature.
 Therefore, the user must design the system cabinet so that the
 average DE surface temperature is as possible as low.

 - DE surface temperature: 45*C or less 5 years

 - DE surface temperature: 46*C to 50*C 4 years

 - DE surface temperature: 51*C to 55*C 3 years

 - DE surface temperature: 56*C and more strengthen cooling power so
   that DE surface temperature is 55*C or less.

 Even if the IDD is used intermittently, the longest service life is 5
 years.

 Note:
 The "average DE surface temperature" means the average temperature at
 the DE surface throughout the year when the IDD is operating.


 Data Space
 ----------
 The IDD manages the entire data storage area divided into the
 following three data spaces.

 - User space: Storage area for user data
 - Internal test space:
     Reserved area for diagnostic purposes
 - System space: Area for exclusive use of IDD itself

 The user space allow a user access by specifying data. These
 space can be accessed with the logical data block addressing
 method. The internal test space is used by Read/write test of
 self-diagnostics test, but user can't use direct access. The  system
 space is accessed inside the IDD at power-on or during the execution
 of a specific command, but the user cannot directly access the system
 space.



 Cylinder configuration
 ----------------------
 The IDD allocates cylinders to the user space, Internal test space,
 and system space.

 Spare areas (alternate areas) for defective sectors are provided in
 the user space. Several sectors in the last track of one cylinder and
 several cylinders (alternate cylinders) in the user space are
 allocated as alternate areas according to the user's assignment (MODE
 SELECT command).


 Track skew and cylinder skew
 ----------------------------
 To avoid waiting for one turn involved in head and cylinder
 switching, the first logical data block in each track is shifted by
 the number of sectors (track skew and cylinder skew) corresponding to
 the switching time.

 At the head switching location in a cylinder, the first logical data
 block in track t + 1 is allocated at the sector position which
 locates the track skew behind the sector position of the last logical
 data block sector in track t.

 At the cylinder switching location, like the head switching location,
 the first logical data block in a cylinder is allocated at the sector
 position which locates the cylinder skew behind the last logical
 sector position in the preceding cylinder. The last logical sector in
 the cylinder is allocated when formatting, and is an unused spare
 sector.

 The number of physical sectors (track skew factor and cylinder skew
 factor) corresponding to the skew time varies depending on the
 logical data block length because the track skew and the cylinder
 skew are managed for individual sectors. The IDD automatically
 determines appropriate values for the track skew factor and the
 cylinder skew factor according to the specified logical data block
 length. The value can be read out by the MODE SENSE or MODE SENSE
 EXTENDED command after the track has been formatted.


 Format capacity
 ---------------
 The size of the usable area for storing user data on the IDD (format
 capacity) varies according to the logical data block or the size of
 the spare sector area.


 Defect list
 -----------
 Information of the defect location on the disk is managed by the
 defect list. The following are defect lists which the IDD manages.

 - P list (Primary defect list): This list consists of defect location
          information available at the disk drive shipment and is
          recorded in a system space. The defects in this list are
          permanent, so the INIT must execute the alternate block
          allocation using this list when initializing the disk.

 - D list (Data defect list): This list consists of defect location
          information specified in a FORMAT UNIT command by the INIT
          at the initialization of the disk. This information
          is recorded in the system space of the disk drive as the G
          list. To execute the alternate block allocation, the FORMAT
          UNIT command must be specified.

 - C list (Certification defect list): This list consists of location
          information on defective blocks which are detected by the
          verifying operation (certification) of the data block after
          the initiation when executing the FORMAT UNIT command. The
          IDD generates this information when executing the FORMAT
          UNIT command, and the alternate block allocation is made
          upon the defective block. This information is recorded in
          the system space of the disk drive as the G list.

 - G list (Growth defect list): This list consists of defective
          logical data block location information specified in a
          REASSIGN BLOCKS command by the INIT, information on
          defective logical data blocks assigned alternate blocks by
          means of IDD automatic alternate block allocation,
          information specified as the D list, and information
          generated as the C list. They are recorded in the system
          space on the disk drive.

 The INIT can read out the contents of the P and G lists by the READ
 DEFECT DATA command.


 Alternate block allocation
 --------------------------
 The alternate data block is allocated to a defective data block (=
 sectors) in defective sector units by means of the defect management
 method inside the IDD.

 The INIT can access all logical data blocks in the user space, as
 long as there is no error. Spare sectors to which alternate blocks
 are allocated can be provided in either "spare sectors in a cylinder"
 or "alternate cylinders".

 The INIT can specify the size and area for spare sectors by the MODE
 SELECT command at the time of the initialization of the disk.
 Both of the following are applicable to the alternate block
 allocation.

 - Sector slip treatment: Defective sectors are skipped and the
   logical data block corresponding to those sectors is allocated to
   the next physical sectors. This treatment is made on the same
   cylinder as the defective sector's and is effective until all spare
   sectors in that cylinder are used up.

 - Alternate sector treatment: The logical data block corresponding to
   defective sectors is allocated to unused spare sectors in the same
   cylinder or unused spare sectors in the alternate cylinder.
   The alternate block allocation is executed by the FORMAT UNIT
   command, the REASSIGN BLOCKS command, or the automatic alternate
   block allocation.

 The logical data block is allocated to the next physically continued
 sectors after the above sector slip treatment is made. On the other
 hand, the logical data block is allocated to spare sectors which are
 not physically consecutive to the adjacent logical data blocks. If a
 command which processes several logical data blocks is specified, the
 IDD processes those blocks in ascending order of logical data block.

 Alternate block allocation during FORMAT UNIT command execution
 When the FORMAT UNIT command is specified, the allocation of the
 alternate block to those defective sectors included in the specified
 lists (P, G, or D) is continued until all spare sectors in the same
 cylinder are used up. When they are used up, unused spare sectors in
 the alternate cylinder are allocated to the subsequent sectors in the
 cylinder by means of alternate sector treatment.


 Formatting
 ----------
 Since the disk drive is formatted with a specific (default) data
 format for each model (part number) when shipped from the factory,
 the disk need not be formatted (initialized) when it is installed in
 the system.

 However, when the system needs data attributes different from the
 default format, all sides of the disk must be formatted (initialized)
 according to the procedures below. The user can change the following
 data attributes at initialization:

 - Logical data block length

 - Number of logical data blocks or number of cylinders in the user
   space

 - Alternate spare area size


 Self-diagnostics
 -----------------
 The IDD has the following self-diagnostic function. This function
 checks the basic operations of the IDD.

 - Initial self-diagnostics

 - Online self-diagnostics (SEND DIAGNOSTIC command)

 For a general check of the IDD including the operations of the host
 system and interface, use a test program that runs on the host
 system.


