Western Digital WD1007A-WAH User manual

USER’S GUIDE
WD1007A-WAH/WA2
Winchester/Floppy
Disk Controller
Important Information
Do Not Discard

1.0 Document Scope
This document describes installation of the WDl007A-WAH/WA2 Winchester/Floppy
Disk Controller in the IBM* Personal Computer AT*. If you have an AT compatible,
you should refer to your system manuals or contact your dealer for information
concerning installation of the WDl007A-WAH/WA2. Refer to the following documents
for a more thorough explanation of board functions:
•WDl007A-WAH/WA2 Data Sheet (79-000261)
•WDl007A-WAH/WA2 Application Notes
•WDl007A Support Diskette (Contact your local sales office)
2.0 Description
The WDl007A-WA2 and the WDl007A-WAH are single board Winchester Disk
Controllers designed to interface two ESDI compatible disk drives to the IBM PC/AT or
compatible host computer. The WDl007A-WA2 supports two 5.25 or 3.5 inch floppy
disk drives; the WDl007A-WAH is a hard disk only version of the controller.
The ESDI drives used with this controller generally have two modes of operation, soft
sector and hard sector. At this time the WDl007A-WA2 offers only the hard sector mode
of operation.
In most systems the BIOS and/or operating system supports only the older MFM/ST-506
drives which use 17 sectors per track. The ESDI disk drive typically has 34 sectors per
track when operating in the hard sector mode. To integrate the hard disk drive into the
AT environment, select a drive parameters table that reflects the physical characteristics
of the drive, i.e., the number of cylinders, heads, and sectors per track.
The WDl007A-WAH/WA2 controller has an optional BIOS ROM that provides drive
parameter tables, low-level formatting routines, and surface analysis routines. While
low-level formatting of the drive can be accomplished by several means, Western
Digital recommends that you use the low-level formatting routine present in the
WDl007A BIOS. If your controller does not have the BIOS option, obtain Western
Digital's WDFMT 2.10 formatting utility.
(*) IBM and AT are registered trademarks of International Business Machines Corporation.

3.0 Hardware Installation Instructions
This section briefly describes installation of the WDl007A-WA2. If you wish to install
the disk drive internally, it is best to locate the controller in the closest available
expansion slot relative to the drive. The WDl007A controller can be installed in any 16-
bit slot in the IBM PC-AT or compatible host computer. Connecting cables for the ESDI
hard disk are the same as those used on ST506 type drives. Device ID jumpers are
implemented on the ESDI device just as with an ST506 drive. Verify that the drive is
configured to support the hard sector mode.
CAUTION
Handle the controller board by the ends of the board. Some of the chips are static
sensitive and damage may occur if the board is incorrectly handled.
1. Verify the controller jumper settings. Modification of the standard factor settings on
the controller is rarely necessary. Modify the jumpers only under the direction of a
qualified individual; i.e., your dealer. Figure 1 illustrates the jumper locations. Table 1
lists the jumper default settings for the WDl007A-WA2 and the WDl007A-WAH.
Table 2 provides the various address select ranges and corresponding jumper settings.
The WDlOO7A-WAH can be used as a field replacement board for existing
WD1005WAH boards without reformatting the hard disk drive. The WDl005WAH
firmware does not recognize the Set Unformatted Bytes per Sector command, so you
must set jumper/switches on the drive to the desired sectors per track. Substituting the
WD1007A-WAH board and installing a jumper at W8 precludes the use of the Set
Unformatted Bytes/Sector command. When in the WDl007A-WA2 mode (no jumper on
W8), the ESDI drive is forced to 35 sectors per track by the Set Unformatted Bytes per
Sector command. The interleave ratio is 1:1.
2. Remove or disable any other floppy controller in your system if you are installing the
WDl007A-WA2.
3. Verify termination of the last hard disk drive. Verify proper setting of drive select
switches on the drive, if necessary. Do NOT use the drive's radial select option. Refer to
the drive owner's manual for information about proper drive termination and select
switches.
4. Remove the blank expansion slot bracket. Put the bracket away and save it for
possible future use. The bracket screw will be used to hold the controller board in place.

5. Connect the 34-pin control cable to Jl connector. Keyed connectors prevent reversal
of the cables.
6. Connect the control cable to the hard disk drive(s).
7. Attach a 20-pin data cable to J2 connector (for Drive 0).
8. Attach a 20-pin data cable to J3 connector (for Drive 1).
9. Connect the cable(s) to the proper hard disk drive(s).
10. Attach the 34-pin daisy-chain cable to J4 connector.
11. Connect the cable to the floppy drive(s).
12. Attach Winchester activity LED connector to J5.
13. Install the controller board into the expansion slot. Ensure that the board is seated
properly by pressing down on both ends of the board. Secure the board with the bracket
screw.

FIGURE 1. CONTROLLER MODULE LAYOUT
TABLE 1. JUMPER DEFAULT SETTINGS
JUMPER FUNCTION WDl007A-WA2 WDlOO7A-WAH
BIOS Address Select (C8000-09FFF) W1 2-3 WI 2-3
BIOS Address Select W2 2-3 W2 2-3
BIOS Shadow RAM Enabled W3 Jumper W3 Jumper
Floppy Controller Enabled W4 No Jumper
Single Spindle Speed Selected W5 No Jumper
Floppy Address Select (3FX) W6 2-3
Floppy Drive Select W7 1-2
WD1007 Mode W8 No Jumper W8 No Jumper
Chassis Ground Disconnected W9 No Jumper W9 No Jumper
Digital Input Register Unlatched W10 No Jumper W10 No Jumper
Diskette Change Enable with FDC Option W11 Jumper W11 No Jumper
Secondary Address Select (1 FX) W12 No Jumper W12 No Jumper
Floppy Controller Enabled - In Etch W13 Uncut
Sector Translation Enabled W14 No Jumper W14 No Jumper
ECC Length Select (4 Bytes) W15 No Jumper W15 No Jumper

TABLE 2. ADDRESS SELECT JUMPERS
Floppy Drive and Data Rate Selection Control
BIOS ADDRESS RANGES JUMPER SETTINGS
W1 W2 W3
C8000-09FFF 2-3 2-3 Jumper
CA000-CBFFF 2-3 1-2 Jumper
CC000-CDFFF 1-2 2-3 Jumper
CE000-CFFFF 1-2 1-2 Jumper
FLOPPY ADDRESS RANGES W6
37X
3FX
PRIMARY/SECONDARY HARD W12
DISK ADDRESSES
1FX No Jumper
17X Jumper
Address Select Jumpers
Table 2, Address Select Jumpers, lists the various jumper configurations for address
selections for both the hard drive and the floppy drive. Jumper connections Wl-W2
select the BIOS ROM/RAM memory addresses. The default address range (C8000-
C9FFF) is factory set. Jumper connection W3 enables the ROM/RAM BIOS when it is
jumpered.
Jumper connection W6 selects the floppy drive's address ranges. The default range is
3FX.
The module's primary hard disk address range is (1F0-lF7 and 3F6-3F7). To select the
secondary hard disk address range (170-177 and 376-377), jumper the Wl2 connector.
Diagnostic Register Latch Control
When installed, jumper connection Wl0 enables the diagnostic Digital Input Register for
operation in the latched mode; i.e., the register outputs latch when the register is
accessed. The jumper is normally not used.
WD1018 Mode Control
Jumper connections W8, W14, Wl5 provide three external mode selects to the control
processor.
W8 Jumper Connection
W8 (No Jumper) - This is the normal WDl007A-WAH/WA2 mode. The firmware forces
a 10 Mhz ESDI drive to 35 sectors per track when using the Set Unformatted Bytes per
Sector command. It is not necessary to set the drive's jumpers and switches for the
desired number of sectors per track. This mode supports a 1:1 interleave.
W8 (Jumper) - This mode allows the l007A-WAH to be used as a replacement board for
existing WDl005-WAH boards without reformatting the drive. The controller reads the
Unformatted Bytes per Sector from the drive.

Wl4 Jumper Connection
Because some of the older operating systems can only recognize 17 sectors per track or a
maximum of 1048 cylinders per drive, the WDl007A-WA2 provides a translation
scheme so that ESDI hard disk drives can be fully utilized in the PC/AT environment.
W14 (No Jumper) - The translation mode provides two types of physical to logical
translation.
Wl4 (Jumper) - Physical to logical translation by the firmware is disabled.
Wl5 Jumper Connection
The purpose of this jumper is to support either four or seven bytes of syndrome during
Read or Write Long commands. Four bytes of ECC is the default mode. Installing the
jumper provides seven bytes of ECC.
W15 (No Jumper) - 4 Bytes ECC
W15 (Jumper) -7 Bytes ECC

Floppy Drive and Data Rate Selection Control
W5 Jumper Connection
Jumper connection W5 selects either a single speed or a dual speed drive. A jumper is
not normally installed, causing selection to default to a single speed drive and 125
nanoseconds precompensation.
W5 (No Jumper) - Single Speed
W5 (Jumper) - Dual Speed
W7 Jumper Connection
The WDl007A-WA2 supports 5.25 and 3.5 inch floppy disk drives. Install Jumper W7
(1-2).
W4 and W13 Jumper Connections
Jumper connectors W4 and W 13 enable the floppy drive controller.
Floppy
Controller W4 Wl3in etch
Enable No jumper Uncut
Disable Jumper Cut
Wl1 Jumper Connection
Jumper Wl1 is the disk change input signal, and must be jumpered if floppy drives are
installed.
Mounting Bracket Jumper
Jumper connection W9 allows grounding of the module mounting bracket to chassis or
logic ground. The jumper is not normally used.
Chassis ground connected 2-3
Digital ground disconnected 1-2
4.0 Software Instructions
In order to use an ESDI drive in a given system, three steps must be followed:
1. Low-level formatting: Use WDFMT, third party software, or the WDl007A BIOS.
2. Active drive partitioning: Use MSDOS* 3.3 (FDISK) or other operating systems that
allow partitioning, such as SCO XENIX*.
3. High-level formatting: Use the operating system's normal "Format C:(or D:)/S"
command.
(*)MSDos and XENlX are registered trademarks of Microsoft corporation.

4.1 Configuring Your Drive
There are two types of BIOS that can play a role in the use of the WD1007A with the
ESDI drive: the system BIOS and the WD1007A BIOS. If the system BIOS is used, the
exact physical drive parameters for the drive must be present in the system BIOS tables.
In terms of maximum flexibility and adaptability with different drives, Western Digital
recommends the use of the WD1007A BIOS.
4.1.1 Using the System BIOS
The system BIOS refers to the BIOS that is controlling the computer, i.e., Phoenix, IBM-
AT, Faraday. If the appropriate drive parameter tables are present, the system BIOS can
be used, along with the operating system (MSDOS, SCO XENIX) to partition and per-
form high level formatting of the drive.
Examine the system parameter tables using one of the following three methods:
1. To determine if a system BIOS has the physical drive parameters required for your
ESDI drive, use the set-up diskette for your system to see if the appropriate number of
heads, cylinders and sectors per track are listed. If they are not listed, the system BIOS
probably does not have the required parameter tables. Use other means, such as
WDFMT or the WD1007A BIOS, to perform a low level format.
2. Another way of examining the system parameter tables to determine if the drive is
listed in the BIOS is to use the DOS Debug Utility.
Although some systems locate drive parameters in other locations, the standard location
in the AT BIOS is F000:E401. The proper command at the DEBUG prompt (-) is as
follows:
df000:e401 <CR>
This corresponds to drive type 1 and will display 8 lines of data from the BIOS ROM.
By entering another " d" at the DEBUG prompt, another eight lines of data will be
displayed, corresponding to drive type 2, etc. This procedure is continued until all drive
parameter information for all drive types is displayed. If your drive's parameters are
encountered in this process, the system BIOS recognizes your particular drive.

Each parameter table has 16 bytes of data. Data from the BIOS ROM is displayed in
hex, least significant byte first. This data breaks down as follows:
Bytes 1 & 2 Number of Cylinders
Byte 3 Number of Heads
Bytes 4 & 5 Not Used
Bytes 6 & 7 Write Precompensation Cylinder
Byte 8 Not Used
Byte 9 Control Byte (= 08H for 8 heads)
Byte 10-12 Not Used
Bytes 13 & 14 Landing Zone 3
Byte 15 Sectors per Track
Byte 16 Not Used
3. There is also a way of using the DOS DEBUG utility to confirm the parameters for
the current drive selected. This is done through the INT 41 (located at d0: 104) and the
INT 46 (located at dO: 118) handlers. INT 41 corresponds to the address of the current
selected parameters for drive 0, and INT 46 corresponds to the address of the current
selected parameters for drive 1.
To see the current selected parameters for drive 0, the proper command at the DEBUG
prompt (-) is:
d0: 104
The first four bytes displayed correspond to the offset (two bytes) and segment 6 (two
bytes) of the location of the selected parameters.
For example, if after entering d0: 104, the result is:
30 IF
00 C8 AB 73.. .<=>Location C800:1F30
[offset] [segment]
then the current selected parameters are located at address C800:1F30. Type
DC800:1F30 at the DEBUG prompt to display the 16 bytes of selected drive parameters.
If, after using the above methods, you verify that the system BIOS does contain the
physical parameter tables for your drives, use WDFMT to low level format the drive,
FDISK (MSDOS 3.3) to partition it, and the "Format C:(D:)/S" command to perform the
high-level format.