
                                        3

                          HOW TO INSTALL YOUR SOFTWARE

Now that you have installed the WD1004 or WD1004A hardware, you need to install 
the software that tells your computer how to use the hardware.

Software Installation Summary

The software installation consists of the following three procedures:

  -  Low Level Format 

       -  use pre-selected configuration (factory default drive table)

       -  use dynamic configuration (you type disk characteristics)

  -  Partition Hard Disk

       -  use DOS FDISK utility program

  -  High Level Format

       -  use DOS FORMAT utility program

You will find it easier to install the WD1004 or WD1004A software, if you first 
read the complete instructions.

Your software installation begins by using either the low level format with a 
pre-selected configuration or a low level format with a dynamic configuration.

Use the low level format with a pre-selected configuration when you are 
installing a hard disk drive whose disk characteristics are the same as those 
in Table 1-1 on page 1-2.

If you have a drive with parameters that are different from those in Table 1-1, 
then you will use the low level format with a dynamic configuration. The 
dynamic configuration is a process whereby you type the characteristics of your 
hard disk drive into the computer rather than using a pre-set drive table. If 
you use the dynamic configuration, you need to locate and enter parameter 
values for the drive and to decide whether to do a virtual split.

Your software installation ends by using the DOS utilities: FDISK and FORMAT.

Where the instructions require you to shift between the text in this chapter 
and Appendix A, step numbers are kept consistent in both sections.

If you are installing a drive with parameters that are different from the 
parameters in Table 1-1, skip the following section "Low Level Format (Pre-
selected Configuration, 32 MB)" and instead go to Appendix C, "Dynamic 
Configuration."














If you are installing a drive with parameters that are the same as the 
parameters in Table 1-1 on page 1-2, use the low level format with a pre-
selected configuration, which begins on the next page.

                                     CAUTION

           Do NOT start the low level format until you have a backup copy of 
           the information on your hard disk. This warning usually applies to 
           previously used hard disks.
           
           When you have a new hard disk, you usually do not have information 
           to backup except in the case where your dealer installs some 
           applications software on your unit.
            

LOW LEVEL FORMAT (Pre-selected Configuration, 32MB)

Before you start, place a DOS startup diskette in your computer and turn the 
power to your computer ON. Then proceed to the A>> prompt.

See your DOS manual if you need help getting to the A>> prompt.

1.   At the A>> prompt, place a diskette with the Debug program 
     in drive A, then 

     Type:   DEBUG

     Press  <Enter>

2.   At the debug prompt (-),

     Type:  g=c800:5

     Press <Enter>

3.   The low level format program displays the following:

     Super Bios Formatter II Rev.1.0 (C) Copyright Western Digital Corp.1988

     Current Drive is C:, Select new Drive or RETURN for current.

     Go to step 3A or step 3B.

3A.  Drive C is your first drive. To remain at drive C

     Press <Enter>

     Now go to step 3C.

3B.  Drive D is your second drive. To change the drive from C to D

     Type:  D

     Press <Enter>













     This changes the drive that you will format. Now go to step 3C.

3C.  The system displays the following:

     Current Interleave is 4, Select new Interleave or RETURN for current.

     Press <Enter>

     Go to either step 3D or 3E. See Appendix A for explanation of interleave.

3D.  To change the current interleave value, type a new value and

     Press <Enter>

3E.  To keep the current interleave value

     Press <Enter>

4.   When the following prompt appears:

     Press "y" to begin formatting drive C with interleave 04

                                     CAUTION

           Do NOT start the low level format until you have a backup copy of 
           the information on your hard disk. This warning usually applies to 
           previously used hard disks.
           
           When you have a new hard disk, you usually do not have information 
           to backup except in the case where your dealer installs some 
           applications software on your unit.
            

5.   To start the format for drive C with interleave 4,

     Type:  Y

     Press <Enter>

Then follow the instructions on your computer screen. When the format starts 
several messages may appear or you may see the word "formatting...."

The format process takes several minutes depending on the drive parameters.

6.   When the format is completed, the following displays:

     Format Successful

If you have a second drive to format repeat the step for the low level format. 
When you format the second drive, be sure to follow step 3B to switch the 
current drive from C to D.














Otherwise, you are done with this phase of the installation and can go to the 
next section, "Final Steps."

**************************************************************************
FINAL STEPS
**************************************************************************

After you complete the low level format on your hard disk drive, you need to 
partition your drive and do a high level format before you can use your hard 
disk for the first time. The DOS programs: FDISK and FORMAT do this.

FDISK and FORMAT are usually located on the supplemental DOS diskette.

Partition Drive

The FDISK program divides the drive into areas called partitions and prepares 
your hard disk for use with an operating system, such as MS-DOS.* You can 
select one partition which takes up your entire disk or several partitions, 
each occupying a portion of the disk. 

Each partition can have its own operating system.

FDISK Utility

If you just completed the low level format, the DOS diskette is in your 
computer and the A>> prompt is on your screen.

To partition your hard disk with FDISK, follow the instructions below.

1.   Make sure that the DOS diskette with FDISK is in drive A.

2.   At the A> prompt, 

     Type:  FDISK

     Press <Enter>

FDISK displays a series of menus. See your operating system manual for details 
on how to partition a hard disk. If in doubt, use the default values.

Partition Second Disk Drive

If you have two hard disk drives or created a virtual disk on your hard disk 
drive, then you must partition each drive or logical drive.

After you partition drive C, repeat the above steps. To partition drive D, 
select partition second hard disk from the menu.

High Level Format

As the final step to the software installation, you need to use the DOS FORMAT 
utility, which prepares the hard disk to accept MS-DOS files.














The DOS utility program, FORMAT, will locate and mark as bad, media defects 
(bad tracks). Therefore if you did not mark the tracks bad during the low level 
format, this step does it for you automatically.

FORMAT Switch "/S"

FORMAT allows you to set certain "switches" which control various aspects of 
the procedure. The /s switch copies the operating system from the disk in the 
default drive (or the A drive) to the newly formatted disk.

This allows you to start your operating system from your hard disk.

To use the FORMAT utility and load the operating system onto your newly 
installed hard disk drive, follow the steps below.

1.   Make sure that the diskette with FORMAT is in drive A.

2.   At the A> prompt

     Type: FORMAT C:/S

     Press <Enter>

Follow the instructions on the screen to complete the process. See your 
operating system manual for details. 

At this point your hard disk is fully initialized and the system can start DOS 
from your hard disk.

High Level Format Second Disk Drive

If you partitioned your hard disk drive into more than one virtual disk, you 
must high level format each logical drive.

After you format drive C, repeat the above steps to format drive D, except for 
the following instructions:

At the A> prompt,

     Type:  FORMAT D:

     Press <Enter>

Follow the instructions on the screen to complete the process. See your 
operating system manual for details. 

You are now ready to go to the next chapter.


                                        4

                         HOW TO CHECK YOUR INSTALLATION

After you completed the hardware installation, software installation, and use 
the FDISK and FORMAT C:/S utilities, you are ready to start using your system.












Start System From Hard Disk

You are ready to start your system using your newly installed hard disk drive 
and WD1004 or WD1004A board.

Remember: You must remove the diskette from drive A or else the system will 
start from drive A.

To start the system

1.   Simultaneously press the <Ctrl> <Alt> <Del> keys.

2.   The system should respond, several screens may flash, and finally the C> 
     prompt will appear.

You may have to enter the date and time before the C>> prompt appears. This 
depends on how your system is set.

Final Check

As a final check, you will start the system after the power has been turned 
off.

1.   Turn the computer OFF and wait 30 seconds.

2.   Turn the computer power ON.

3.   The system should respond, several screens may flash, and finally the C> 
     prompt will appear.

You may have to enter the date and time before the C>> prompt appears. This 
depends on how your system is set.

Installation Complete

You are now done. The next time you can start your system from the hard disk.


                                        5

                             HOW TO HANDLE PROBLEMS

If you had a problem with your system, first re-read the instructions to be 
sure that you followed them correctly. Check that you typed information EXACTLY 
as instructed.

Repeat the procedure a second time to verify that you get the same error, then 
check the next section, "If You Have a Problem."

If You Have a Problem

First check your physical installation. Check for reversed cables, an 
overloaded system power supply, incorrect drive selection, etc.












This section lists some common problems and possible solutions to try if you 
have problems when you install your controller.

PROBLEM:   No response or blank screen during installation.

SOLUTION:  Change cables. Do NOT use floppy cables.

PROBLEM:   Winchester activity LED on front of drive is always on.

SOLUTION:  Check cable connections. Check that pin 1 is connected to 
           pin 1 and if not reverse connection. Replace cables. Check whether 
           the drive has malfunctioned.

PROBLEM:   "Nothing done exit" appears when you start the low level format 
           program.

SOLUTION:  You did not press the <<Y>> key. Restart low level format 
           at step 1.

PROBLEM:   "Error Reading Fixed Disk" when booting the system.

SOLUTION:  DOS partition not active. See FDISK instructions in your DOS 
           manual.

PROBLEM:   "Hard Disk Drive Not Ready" or "01" Error Code.

SOLUTION:  System BIOS ROM does not support Winchester (WD1004 or WD1004A) 
           controller and drive. Update system BIOS ROM. Overloaded power 
           supply. Update system power supply.

PROBLEM:   Error code "80" while doing the low level format.

SOLUTION:  Drive select jumper on the hard disk drive unit is set incorrectly 
           (see Chapter 1), or the cables are backwards, i.e., Pins 1 & 34 
           switched or connector cables J2 & J3 switched. Also bad cables, no 
           power to drive, or bad drive.

PROBLEM:   Error code "40" or "20" appears on screen.

SOLUTION:  Check cable connections.  Check that pin 1 is connected to 
           pin 1 and if not reverse connection. Replace cables. Check whether 
           the drive has malfunctioned.

PROBLEM:   After you do a high level format (Format C:/S), the message 
           "Insert disk and press ENTER." appears. The system thinks drive C 
           is a floppy disk drive.

SOLUTION:  Computer motherboard switches are set for the incorrect number 
           of floppy disk drives. Check to see if RAM disk drivers are present.

PROBLEM:   "Bad Track 0" using DOS 3.1.

SOLUTION:  Make a config.sys file with BUFFERS=99. Reboot to load the 
           configuration.













PROBLEM:   "Bad Track 0" using DOS 2.1. (DOS 2.1 cannot support bad tracks 
           beyond the 16.7 MB segment.)

SOLUTION:  Upgrade system to DOS 3.1 or LATER. 

PROBLEM:   My 32MB hard disk drive has the same parameters as those in 
           Table 1-1 on page 1-2, which is 26 sectors per track. But when I 
           looked at Table B-4, the default value shows 17 sectors per track. 
           What's wrong?

SOLUTION:  Nothing. Notice that the default value in Table B-4 also selects 
           sector translation. If your drive parameters are the same as those 
           in Table 1-1, then you can use the factory pre-selected drive table 
           and use the pre-selected configuration. See Appendix B for more 
           information on translation.

PROBLEM:   None of the suggestions seem to help.

SOLUTION:  Call your dealer.


                                        A

                INSTALL A SECOND DRIVE ON AN EXISTING CONTROLLER

This section tells you how to install a second fixed hard disk drive on an 
existing WD1004 or WD1004A controller board. You do not have to remove the 
existing WD1004 or WD1004A controller board,but you may have to remove the 
fixed hard disk so that you can remove the termination resistor. (This depends 
on the location of the fixed disk and the termination resistor.)

Do not attempt to install your hardware unless you have compared your drive 
against the default drive parameters on page 1-2, and set the drive number and 
removed a termination resistor as explained starting on page 1-9.

This installation requires you to remove the cover from your computer. See your 
computer manual for exact instructions on how to remove the cover.

You need a 34-pin hard disk control cable in a daisy chain configuration and 
you also need a second 20-pin data cable.

XT hardware limits you to two fixed hard disks. If you are installing a second 
drive on your system, then the WD1004 or WD1004A board must be the only hard 
disk controller in your system.

1.   Turn your computer power switch to OFF and unplug the power cord.

2.   Use a screwdriver to loosen the cover screws. Then remove the computer 
     cover, so that you can see the expansion slots.

3.   Place the new hard disk drive unit into the computer case and mount per 
     the manufacturer's installation instructions.













4.   Look and see which expansion slot has the WD1004 or WD1004A board. You may 
     have to lift the WD1004 or WD1004A board out of the slot to access the 
     connectors.

5.   Check if your existing 34-pin wide control cable is a daisy chain cable. A 
     daisy chain cable has 3 connectors. If the cable is not a daisy chain 
     cable, then remove the 34-pin wide control cable from the WD1004 or 
     WD1004A board and the existing hard disk drive unit. You will replace this 
     cable with a daisy chain cable in the next step.

     Leave the 20-pin cable attached to the board and the drive unit.

6.   Connect cables to new hard disk drive unit. Follow steps A, B, and C.

     You may have to leave the fastening screws on the drive case loose to 
     connect the cables.

     Remember: Connect Pin 1 to Pin 1. Pin 1 of the cable connector is marked 
     and is on the color coded edge of the cable. Pin 1 on the controller board 
     is shown in Figure 1-1 and Figure 1-2.

     A.    (Omit this step if you are using an existing daisy chain cable)
           Connect the 34-pin (daisy chain wide control cable) end connector 
           on the shorter cable section to the first hard disk drive unit's 34-
           pin connector.

     B.    Connect the 34-pin middle connector on the shorter daisy 
           chain cable section to the second hard disk drive unit's 34-pin 
           connector.

           The longer cable section is unattached for now.

     C.    Connect the second 20-pin data cable to the second hard 
           disk drive unit's 20-pin connector.

7.   Locate the internal 4-pin power connector(s) on your 
     computer. See your computer manual. You need either two internal 
     power connectors on your computer or you need a "y" adapter to split 
     the power cable.

     Connect the second drive unit to the second power connector 
     plug or to the "y" adapter.

8.   Connect the free end of the 34-pin (wide control cable) 
     connector to J1 on the controller board. Attach Pin 1 of the cable 
     connector to Pin 1 on the controller board.
     
     Note: Pin 1 on the controller board is shown in Figure 
     1-1 and Figure 1-2.
     

9.   Connect the free end of the 20-pin data cable from the 
     second drive to J3 on the WD1004 or WD1004A controller board. Attach 
     Pin 1 on the cable to Pin 1 on the controller board.
     













10.  Place extra cable lengths so that they are out of the 
     way.
     
     
                                     CAUTION

           Do NOT pinch the cables when you arrange them inside your computer 
           case. Do not let the cables lay between the cover and an internal 
           board. Do not obstruct air flow from fans or vents.
            

11.  Replace the computer cover, then the power cord. Your hardware controller 
     installation is complete. However, your WD1004 or WD1004A controller board 
     is really a complex circuit composed of both hardware and software, so 
     that while the hardware installation is complete, you still need to 
     install the software. Go to Chapter 3 for the software installation steps.
     
     Tighten hard disk unit to computer case, if not already done so in step 3.
     

**************************************************************************
INTERLEAVE FACTORS
**************************************************************************

Interleave is a technique that allows the computer to read or write more than 
one sector per track during a single disk rotation.  Example: An interleave 
factor of 4:1 means that after the disk rotates 4 times, the computer has 
accessed all the information on a track.

The interleave factor is system dependent. For WD1004 or WD1004A boards and XT 
compatible computers an interleave factor of 4 is the default. Do not select an 
interleave value less than 4 with the WD1004 or WD1004A board.

**************************************************************************
VIRTUAL SPLIT
**************************************************************************

A virtual split is a logical dividing of the disk drive. When you do a virtual 
format, you make one physical drive appear as two or more disks to the system.

DOS 2.0 allows a maximum of 16 megabytes per drive and DOS 2.1 permits 32 
megabytes per drive. Therefore a 40 megabyte drive must be virtually split in 
order to use all 40 megabytes.

If you have two physical hard disks, do not use the virtual split format.

Select Virtual Split

6.   To select the virtual configuration for your drive, 
     answer the prompt, 
     
     Are you virtually configuring the drive - answer Y/N
     











     
     Type: Y
     
     Press <Enter>
     
     The following prompt displays:
     
     Key in cylinder number for virtual drive split as vvvv...
     where:vvvv = number of cylinders for drive C: (1-4 digits)
     
     Enter the number of cylinders for drive C. (To calculate 
     the cylinders, see page A-11.)
     
     Follow the completed entry by pressing the <<Enter>> key. 
     
     The number you entered represents the number of cylinders on drive C. The 
     remaining cylinders are assigned to drive D during the virtual split 
     process.
     
     The system displays the following prompt:
     
     Press "y" to begin formatting drive C with interleave 04
     
     Type: Y
     
     Press <Enter>
     

7.   When the prompt to enter bad tracks displays, see the section on bad 
     tracks. When the low level format is complete, the following message 
     displays:
     
     Format Successful
     
     

Do not use the low level format program on the second "virtual" drive. The 
virtual drive is formatted when you select the virtual format option. Go to 
section, "Final Steps," in Chapter 3.

**************************************************************************
BAD TRACKS
**************************************************************************

Because a hard disk is a physically manufactured item, it sometimes has 
physical defects. Each drive manufacturer tests their drives and gives you a 
bad track media list, when you purchase the drive. This bad track list is 
usually located on the top of the disk drive case. Locate this list before you 
answer the prompts.

7.   During the format program, you are asked if you want to map the bad tracks 
     by the following prompt:

     Do you want to format bad tracks - answer Y/N












     
     Because of the addressing method used by DOS, marking an entire track bad 
     results in more than one sector being marked as bad. Since DOS limits the 
     number of defects that it accepts, a drive with excessive media defects 
     can cause the FORMAT program to terminate with an error, "TRACK 00 BAD - 
     DRIVE UNUSABLE."
     
     Alternately, you can use the DOS utility program, FORMAT, to locate and 
     mark as bad, media defects. Therefore we recommend that you do not mark 
     the tracks bad; but if you decide that you want to mark the bad tracks, 
     follow the steps below.
     
     Select Map Bad Tracks
     
     To map the bad tracks,
     
     Type: Y
     
     The system displays the following prompt:
     
     Key in bad track list as follows: ccc h...
     
     where:
     
           ccc=bad track cylinder number
           h=bad track head number
           
     
     Enter each value separated by a space and follow the 
     completed entry by pressing the <<Enter>> key.
     
     EXAMPLE:
     
     For a disk with a bad cylinder 160 on head 1 and bad 
     cylinder 161 on head 3
     
     Type: 160 1 161 3 
     Press <Enter>
     
     The bad tracks program displays the following prompt: 
     
     
     More? Y/N
     
     To enter additional bad tracks,
     
     Type: Y
     
     Press <Enter>
     
     and enter more bad tracks.
     
     To terminate the bad tracks program,
     
     











     Type: N
     
     Press <Enter>
     
     Then the following displays:
     
           BAD TRACK MAP
           
           TRACK ADDR                               PROBLEM
           
           cccH                                     USER-SUPPLIED
           
     
     When the format is completed, the message displays:
     
     Format Successful
     
     
     Now go to section "Final Steps" in Chapter 3, to partition 
     your drive and do a high level format.
     

BIOS ROM Incompatibility

The following is a list of XT compatible computers which do not operate with 
the Western Digital BIOS ROM because of a system BIOS incompatibility. Because 
new computers are always being developed, Table A-1 may not be complete; 
however, it is the best list that we have available at this time.
           
           Computer            Model
           
           AT&T                  6300
           AT&T                  6300T
            

If you have one of these computers, you must disable the BIOS ROM by placing a 
jumper resistor at R23 and check that the integrated circuits at U7 and U8 are 
NOT installed. When you do the low level format, skip the directions in this 
guide and instead follow your computer manufacturer's software installation 
instructions for low level formatting.

CALCULATE CYLINDER NUMBER (VIRTUAL SPLIT)

Frequently, when you do a virtual split on a drive you have the desire to 
control the size of each virtual drive. In order to do this, you need to know 
the number of cylinders in each drive. But since you plan to divide the drive 
into only two sections, you only need to know the size of the first drive.

The size of the first disk or disk drive capacity is defined as the number of 
bytes available for a disk drive. Mathematically the drive capacity is defined 
as follows:

     drive capacity = (#cyl)(#heads)(#sectors/track)(sector size)
     
     











     where:
     
     # cyl = determined from the manufacturer or is calculated for virtual 
     drives
     # heads = determined from the manufacturer
     #sectors = 26 (without translation) or 17 (with translation)
     sector size = 512 bytes 
     

EXAMPLE:

To split a 50 megabyte disk drive with 615 cylinders and 6 heads into a 30 
megabyte drive and a 20 megabyte drive, you need to calculate the number of 
cylinders in a 30 megabyte drive.

For a 30 megabyte drive:

     drive capacity = 30 megabytes = (30 megabytes) (1,048,576 
     bytes/ 1 megabyte)
     drive capacity = 31,457,280 bytes
     

To calculate the number of cylinders for a drive, solve the drive capacity 
formula shown above for the number of cylinders. Be sure to use the correct 
units when you do your calculations.

Calculation: 

     (#cyl) =                   drive capacity  
                     (#heads)(#sectors/track)(sector size)
     

For the example 30 megabyte drive with 6 heads, 26 sectors/track, and 512 
bytes/sector

     (#cyl) =                  (30)(1,048,576)            
                               (6)(26)(512)                             
            =     393
     

Thus to split the example 50 megabyte drive into a virtual 30 megabyte drive, 
enter 393 as the number of cylinders. It is not necessary to enter the number 
of cylinders for the 20 megabyte drive; they are automatically calculated.

                                     CAUTION

           Do NOT run IBM Diagnostics on the first logical drive. If you do, 
           then you will DESTROY all information on the second logical drive.
           
            

















                                        B

                                     JUMPERS

The WD1004 board has a row of jumper pins at W17 to W22 and W25 to W28. The 
WD1004A board has a row of jumper pins at W25 to W28. Adding a jumper shorting 
plug at any of these locations, selects a hardware configurations that is 
different from the default value selected by Western Digital.

Jumper Functions (W17 to W22, R23, and W25 to W28)

The following list explains the jumper functions.

  -  W17 & W18 selects factory drive tables for the first 
     hard disk

  -  W19 & W20 selects factory drive tables for the second 
     hard disk

  -  W21 and W22 selects the controller and BIOS address 
     ranges

  -  R23 disables the Western Digital BIOS ROM on WD1004 
     and WD1004A boards

  -  W25 and W26 set sector translation and dynamic configuration

  -  W27 sets the hardware interrupt (IRQ) value for the 
     hard disk drive

  -  W28 allows the controller to operate with an XT computer 
     when the jumper is OUT

Default Values

Tables B-1 through B-5 list the jumper settings. Default factory settings are 
marked with a "" symbol.


Table B-1 Pre-selected Drive Tables

Table     First Drive     Second Drive     Capacity     Heads    Cylinders
Number    W17     W18     W19      W20     

0         in      in      in       in      65MB           6       820
1         out     in      out      in      42MB           4       782
2         in      out     in       out     21MB           2       782
3*        out     out     out      out     32MB           4       615



Table B-2. Select Controller and BIOS Ranges

W21       W22            Controller                BIOS












out*      out*           320-323                   C8000-C9FFF
in        out            324-327                   CA000-CBFFF
out       in             328-32B                   CC000-CDFFF
in        in             32C-32F                   CE000-CFFFF



Table B-3.  Select BIOS ROM

R23               Select BIOS

in                Selects external BIOS
out*              Selects internal BIOS



Table B-4. Select Sectors and Configuration Option

W25       W26     Table          Sectors    Translate     Dynamic

in*        out*   RLL              17         yes           no
out        in     RLL              26         no            yes



Table B-5. Select Hardware Interrupt (IRQ)

W27        Select IRQ

in         selects IRQ2
out*       selects IRQ5


How To Change Jumpers

To change a jumper, you need to either add or remove a tiny jumper plug or bar.

These jumper plugs or bars are not supplied by Western Digital. You need to 
purchase them separately. The jumper plugs are available at most electrical 
suppliers. A typical jumper plug is Berg P/N 76438-101.

Note that the factory default settings have the jumpers out (i.e., not 
installed), except for W25, which is installed. W25 selects 17 sectors per 
track, sector translation, and prevents dynamic configuration.

EXAMPLE

To change the jumper setting to permit dynamic configuration, requires that you 
change the jumper setting at W25 and move the tiny jumper plug to W26.

To change the jumper setting from the default value at W25, take the shorting 
bar from the row of jumper pins it currently occupies at W25, and place it 
across the jumper pins in the new location at W26.













How To Change Jumper Resistors

While the jumper positions at locations W17 to W22 and W25 to W28 contain a row 
of jumper pins, the jumper position at location R23 is actually occupied by a 
jumper resistor. A jumper resistor differs from a jumper pin and shorting 
bar/plug combination. A jumper resistor only has a flat set of electrical 
connections or contact points on the controller board, while a jumper pin and 
shorting bar/plug combination actually contains pins that go above the board's 
surface.

R23 is the only jumper resistor position on your controller board.

                                     CAUTION

           Do not attempt to change the jumper resistor at R23 unless you know 
           how to solder electrical connections. Contact your dealer for advice 
           on soldering jumper resistors.
            

To add a jumper resistor, you can solder 24 gauge wire to the contact points at 
R23.

To remove a jumper that has been soldered into place at R23, you can use a 
soldering iron to remove the connection at R23 or you can cut the jumper 
resistor wire using a small wire cutter.

**************************************************************************
TRANSLATION
**************************************************************************

Jumpers W25 and W25 control the translation mode on your WD1004-27X and WD1004A-
27X controller boards.

Translation mode allows your RLL drive to emulate an MFM drive with 17 sectors 
per track. The translation mode "translates" the physical characteristics of 
your hard disk, so that older system BIOS ROMs or operating systems that only 
supported MFM drives with 17 sectors per track, can now use the physical 
characteristics information supplied by your WD1004 and WD1004A controller 
boards.

This means that you can use a 32MB hard disk drive that has 4 heads, 615 
cylinders and 26 sectors per track without modifying the factory default jumper 
settings for W25 and W26. Even though the factory default values for W25 (in) 
and W26 (out) as shown in Table B-4 list the sectors per track as 17, Table B-4 
also shows that the factory default values for W25 (in) and W26 (out) selects 
sector translation. 

This means that if your drive parameters are the same as those in Table 1-1, 
then you can use the factory pre-selected drive table and use the pre-selected 
configuration.
















                                        C

                              DYNAMIC CONFIGURATION

Do not attempt to start the dynamic configuration unless you have set the 
jumpers, W25 out (i.e, not installed) and W26 in (i.e., installed). See 
Appendix B for more information on jumpers.

The dynamic configuration allows you to enter the disk drive parameters 
yourself.

                                     CAUTION

           Do NOT start the low level format until you have a backup copy of 
           the information on your hard disk. This warning usually applies to 
           previously used hard disks.
           
           When you have a new hard disk, you usually do not have information 
           to backup except in the case where your dealer installs some 
           applications software on your unit.
            

**************************************************************************
LOW LEVEL FORMAT (Dynamic Configuration)
**************************************************************************

Before you start, place a DOS startup diskette in your computer and turn the 
power to your computer ON. Then proceed to the A> prompt. See your DOS manual 
if you need help getting to the 
A>> prompt.

1.   At the A>> prompt, place a diskette with the Debug program in drive A, 
     then 
     
     Type: DEBUG
     
     Press <Enter>
     

2.   At the debug prompt (-),
     
     Type: g=c800:5
     
     Press <Enter>
     

3.   The low level format program displays the following:

     Super Bios Formatter II Rev.1.0 (C) Copyright Western 
     Digital Corp.1988
     
     Current Drive is C:, Select new Drive or RETURN for current.
     
     Go to either step 3A or step 3B.
     












3A.  Drive C is your first drive. To remain at drive C

     Press <Enter>
     Now go to step 3C.
     

3B.  Drive D is your second drive. To change the drive from 
     C to D
     
     Type: D
     Press <Enter>
     
     This changes the drive that you will format. Now go to step 3C
     

3C.  The system displays the following:

     Current Interleave is 4, Select new Interleave or RETURN for current.

     Press <Enter>

     Go to either step 3D or 3E. See Appendix A for explanation 
     of interleave.
     

3D.  To change the current interleave value, type a new value and
     
     Press <Enter>
     

3E.  To keep the current interleave value
     
     Press <Enter>
     

4.   The following displays:
     
     Are you dynamically configuring the drive - answer Y/N
     
     Type: Y
     
     Press <Enter>
     
     The following prompt displays:
     
     
     
     Key in disk characteristics as follows: ccc h rrr ppp ee o
     
     where:
     
     ccc = total number of cylinders (1-4 digits)
     











     h = number of heads (1-2 digits)
     rrr = starting reduced write current cylinder (1-4 digits)
     ppp = write precomp cylinder (1-4 digits)
     ee = max correctable error burst length (1-2 digits), range (5-11 
     bits), default 11 bits
     o = ccb option byte, step rate select, (1 hex digit), range = 0 to 
     7, default = 5
     refer to controller and drive specifications for step rates
     

Check the literature supplied by your hard disk drive manufacturer for these 
values.
     
     
Table C.1 - Select ccb Byte Option

     ccb      Step Rate                  ccb     Step Rate
     

0       3  msec/step                     4       24 msec/step
1      24 msec/step                      5       24 msec/step
2      24 msec/step                      6       24 msec/step
3       8 msec/step                      7        8 msec/step


To determine the ccb option byte value, find the step rate from your drive 
literature and compare that step rate with Table C-1. The ccb value is the 
single digit (between 0 and 7) that corresponds to your drive's step rate as 
listed in Table C-1. When in doubt, use the default ccb value of 5.

5.   Enter each value separated by a space and follow the completed entry by 
     pressing the <Enter> key.
     
     EXAMPLE:
     
     For a ST 238 (Seagate model 238 hard disk drive)
     Type: 615 4 616 616 11 7 
     Press <Enter>
     

After you enter these values, you have to decide whether to perform a virtual 
split.

6.   When the following prompt displays:

     Are you virtually configuring the drive - answer Y/N

     See Appendix A section "Virtual Split" for more information 
     on a virtual split and instructions to select the virtual split.
     
     To ignore the virtual split configuration,
     
     Type: N
     
     











     Press <Enter>
     
     The system displays the following prompt:
     
     Press "y" to begin formatting drive C with interleave 04
     
     Type: Y
     
     Press <Enter>
     
     Then follow the instructions on your computer screen. When the format 
     starts several messages may appear or you may see the word 
     "formatting...."
     

7.   At the prompt, 
     
     Do you want to format bad tracks - answer Y/N
     
     See Appendix A section "Bad Tracks" for more information 
     on the bad tracks option and instructions to select the bad tracks 
     option. Normally, you can ignore the selection here.
     
     To ignore the bad tracks option,
     
     Type: N
     
     Press <Enter>
     
     When the format is complete, the following message displays:
     
     Format Successful
     
     If you have a second drive to format repeat the low level format steps. 
     Otherwise you are done with this phase of the installation and can return 
     to Chapter 3 and go to the section, "Final Steps."
     
     
     Doc. No. 79-000369
     
     Western Digital
     2445 McCabe Way
     Irvine, CA 92714
     (800) 777-4787   (714) 863-0102
     FAX (714) 863-1656  TLX 910-595-1139
     
     WD0044S 2/89 
     