                             EPSON AMERICA, INC.
                          Product Support Bulletin

                 Subject: Equity 386SX Questions and Answers


Date: 10/01/89                                          PSB No: S-0106
Page: 1 of 8                                            Originator: DS/PM


GENERAL:

Q1.  What microprocessor does the Equity 386SX use?

A.   The Equity 386SX utilizes the Intel 80386SX- 16 microprocessor
     running at 8 or 16Mhz. Use of this CPU gives you 386 performance
     and compatibility in a 16-bit based computer architecture.


Q2.  What speed does the Equity 386SX operate at?

A.   The Equity 386SX operates at either a 16Mhz or 8Mhz processor
     speed. The speed can be set by using the CPU speed switch
     located on the front of the machine. At either processor speed, the
     system bus operates at a fixed speed of 8Mhz.


Q3.  What is the Auto Speed function?

A.   The Equity 386SX is capable of operating at 16MHz or 8MHz. Some
     copy-protected applications require the computer to run at 8MHz
     while accessing the program diskette. By enabling the Auto speed
     function the computer automatically switches to 8MHz when accessing
     the diskette drive. It then switches back to 16MHz for optimal
     performance. Auto speed is accessed through the SETUP program
     under the Auto speed option.


Q4.  Does the Equity 386SX use the Phoenix or Award ROM BIOS?

A.   No. All Equity desktop computers utilize a Seiko-Epson proprietary
     ROM BIOS.



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Q5.  Can the Equity 386SX support an 80387 co-processor?

A.   Yes, 80387SX support is available. The Equity 386SX has a socket for an
     optional 80387SX-16 math co-processor which operates at 16MHz. This allows
     extra processing power for math intensive programs like Lotus 1-2-3 or
     AUTOCAD.

Q6.  Can the Equity 386SX use option cards that are available for the
     IBM PC/AT?

A.   The Equity 386SX uses an AT-compatible ISA (Industry Standard Architecture) bus structure that enables you to install any of the
     various add-on products designed for IBM PC, XT or AT computer, such as:
     expanded memory, EGA or VGA video, internal modems and many more. It also
     supports all of the option boards manufactured by Epson for the EOUITY
     series. There are 5 standard I/O expansion slots (one with 8-bit bus and 4
     with 16-bit bus); one proprietary slot occupied by a serial/parallel
     interface card. The 16-bit slots will also accept 8-bit compatible cards.
     The Equity 386SX offers flexibility in tailoring the system to your needs.


Q7.  Are there any tested internal modems that can be used?

A.   The Epson Link PC and the Hayes 2400 baud internal modems have been
     approved.

Q8.  Does the Equity 386SX have a built in PS/2 mouse port?

A.   Yes, it has a PS/2 compatible mouse port on the rear panel of the computer.
     The connector is a 6 pin mini DIN for an IRO12 mouse or other device.

Q9.  Can the Equity "+" keyboard be used on this machine?

A.   The Equity "+" keyboards are the same as the keyboards used on the Equity
     386SX and are thus interchangeable. The cable on the Equity 386SX keyboard
     is longer in length than the cable used on the "+" keyboard.



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Q10. What is the Password Security?

A.   This system provides three levels of password protection against
     unauthorized access: password before boot, network-server mode password and
     password disable. The password is user definable and consists of a 7-byte
     (character) string. The password protection feature is not case sensitive.
     When the system is booted for the first time, or the password has been
     disabled and re - enabled by moving jumper J1 on the system board, the user
     defines and enables the password using the Setup utilit,v on the Reference
     disk.

Q11. What terminal emulation boards are compatible w/ the Equity 386SX? 

A.   The following products have been tested and approved:

                3278/79 Emulation Adaptor       IBM
                IBM 5250 Board                  IBM
                IRMA/2                          DCA Inc.
                SDLC                            IBM


Q12. Does the Equity 386SX have a battery for the Real Time Clock?

A.   The Equity 386SX is using a "Dallas" model DS1287 which incorporates an
     HD146818 compatible real-time clock with an internal battery.

Q13. What VGA adapters are compatible with the Equity 386SX?

A.   The following VGA adapters have been tested in the Equity 386SX:

                Paradise VGA Plus 16 Card
                Paradise VGA Professional Card
                Video Seven Fastwrite Card

Q14. Can the serial and parallel ports be disabled?

A.   No. The parallel and serial ports auto configure at boot up from the
     BIOS ROM. They are set up as LPT1 and COM1 respectively and there are no
     hardware jumpers or DIP switches to set them to LPT2 and COM2.



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Q15. How many internal device bays does the Equity 386SX have and will 
     it support a full- height device?

A.   The Equity 386SX has 3 half- height bays to support up to 3 half-height
     devices. The separator between bays 2 & 3 can be removed to allow for the
     installation of a full-height device.


Q16. How many wait states does the Equity 386SX have?

A.   At 16MHz the system utilizes a "1/4 wait state" architecture for memory
     access and 0 wait states for ROM BIOS access on the motherboard. At 8MHz,
     memory and ROM BIOS access require 1 wait state; on the expansion bus,
     all memory or device requests are 1 wait state. If additional wait states
     are required, devices on the I/O channel hold the READY signal low thus
     wait states are generated until the device can respond to the CPU.


Q17. Are the wait states user selectable?

A.   No, the Equity 386SX automatically inserts them when needed after the
     command phase of the processor clock cycle.


Q18. How many jumpers are on the system board?

A.   There are five (5) jumpers on the system board:

        System Board:
                     Jumper 1: Co-Processor Installed/Not Installed
                               1-2: Installed
                             * 2-3: Not Installed
                     Jumper 2: Password
                             * 1-2: Password Enabled
                               2-3: Password Disabled


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                     Jumper 3: Embedded HDD Interface Enable/Disable
                               1-2: Embedded HDD Interface Disable
                             * 2-3: Embedded HDD Interface Enable

                     Jumper 4: BIOS EPROM Type
                             * 1-2: Selects 27256 Kb ROM
                               2-3: Selects 27512 Kb ROM

                     Jumper 5: IRQ 12 Select
                               1-2: IRO 12 From Option Slot
                             * 2-3: IRQ 12 From Built-in Mouse

        Memory Board:
                     Jumper 1: Built in Buffers Enable/Disable
                               1-2: SlMM's Installed, Buffers Enabled
                             * 2-3: SlMM's Not Installed, Buffers Disabled

        NOTE - "*" Indicates factory settings.

HARD DISK DRIVES:

Q19. What kind of hard disk drives are available for the Equity 386SX?

A.   The Equity 386SX is available in two hard disk configurations. A 40Mb 3.5"
     hard disk, (Conner CP-344, 29ms access time) and a 100Mb 3.5" (Conner
     CP-3104, 28ms access time) hard disk are available. These hard disk
     drives offer a 1:1 interleave and use embedded controllers with an AT
     interface. When installing the 40Mb drive use type 59 and with the
     100Mb drive use type 60 in SETUP.

Q20. What hard drive controller is used in the Equity 386SX?

A.   The Equity 386SX uses a controller embedded on the hard drive. This
     controller connects to a Task File Host interface that is integrated in the
     system board.

Q21. Can the Equity 386SX use other hard disk drives and controllers?

A.   Yes, the Host Interface on the system board can be disabled and other third
     party hard drive controllers and drives can be used. The interface can be
     disabled by setting Jumper J3 to position 1- 2. Other embedded controller
     AT-type drives can also be used with the Host Interface.




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Q22. What extended hard drive support is available in the ROM BIOS that 
     comes with the Epson Equity 386SX?

A.   The Seiko-Epson BIOS will directly support hard drives that range in size
     from 10Mb to 153Mb. There is direct support for the Seagate ST- 251 and the
     ST- 4096 hard disks, as well as, several ESDI drives. By providing this
     support for 3rd party hard disk drives, the Equity 386SX has the capability
     to use most 3rd party 8-bit and 16-bit hard disk controllers. SCSI drives
     have their own controllers attached to the drive and should work correctly
     when attached to the bus with a host adapter.

     The Equity 386SX also has a User Definable setting that allows you to set
     up hard disk drives that are not supported by the Equity 386SX Drive Type
     Table. In SETUP, a sub-menu lists the settings you can change for each
     drive: the number of cylinders (tracks), the number of read/write heads,
     the number of sectors, the precompensation cylinder, the landing zone
     (the cylinder on which you want to park the heads when moving the
     computer), and the total storage capacity in megabytes.

FLOPPY DRIVES:

Q23. What types of floppy disk drives will work on the Equity 386SX?

A.   The Equity 386SX comes standard with a 3.5" 1.44Mb floppy disk drive. There
     is built-in BIOS support for industry standard 360Kb and 1.2Mb 5.25" half
     height floppy disk drives as well as the 720Kb 3.5" floppy drive. All four
     drive sizes are available from Epson.

Q24. Will the Equity 386SX support 3 floppy disk drives?

A.   No, not directly. The Epson controller and ROM BIOS supports a maximum of
     two floppy drives. The internal floppy controller cannot be disabled.

Q25. Can the floppy disk controller be disabled?

A.   No. The floppy disk controller is integrated in the system board and there
     are no jumpers to enable or disable it. If an additional or 3rd party board
     is present the BIOS ROM auto-configure at bootup.


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MEMORY:

Q26. What type of RAM chips are used in the Equity 386SX?

A.   The Equity 386SX utilizes eight (8) 514256- 70 (256x4), 70 nSec RAM chips
     plus parity on the system board.

Q27. How do I increase the memory of the Equity 386SX?

A.   The standard Equity 386SX system includes 1 Mb of on-board memory. You can
     add SlMMs (single in-line memory modules) for increased on-board memory by
     installing them onto the PAN-RM board already in the Equity 386SX. With
     added SlMMs, the total amount of on- board memory in the computer must be
     one of the following: 2Mb, 4Mb, 6Mb, 8Mb, 10Mb 12Mb or 14Mb.

     There are 16 SIMM sockets inside the Equity 386SX. The 4 centermost sockets
     MUST contain 70 nSec 256Kb SlMM's. All other sockets can contain one 256Kb
     or 1Mb SIMM. The following table shows possible SIMM configurations for the
     Equity 386SX.

            HIGH BYTE           |          LOW BYTE

SIMM Location:                                                       Total Mem
lA  2A  3A  4A  5A  6A  7A   8A   12A 13A 14A 15A 16A 17A 16A 19A
9H  6H  7H  6H  SH  4H  3H   2H   2L  3L  4L  5L  6L  7L  6L  9L

                        K    K    K   K                                  2MB
                    M   K    K    K   K   M                              4MB
                M   M   K    K    K   K   M   M                          6MB
            M   M   M   K    K    K   K   M   M   M                      8MB
        M   M   M   M   K    K    K   K   M   M   M   M                  lOMB
    M   M   M   M   M   K    K    K   K   M   M   M   M   M              12MB
M   M   M   M   M   M   K    K    K   K   M   M   M   M   M  M           14MB


                     Legend:
                     K = 256Kb x 1 x 9 SlMM's
                     M = 1Mb x 1 x 9 SlMM's

         Total Mem includes the standard 1MB of System Memory

Memory can also be expanded through the use of third party memory 
boards using an I/O slot.



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Q28. What SIMM chips should be used when adding memory to the Equity 386SX?

A.   Use the Epson 70 nSec - 9 bit SIMM module kits, either 1-MB kit (4-256Kb
     SIMM's, Part # A808231) or the 2MB kit (2-1Mb SIMM's, Part # A808101), to
     extend the system memory. Should you need to use third party SIMM modules
     we recommend the following:

                Toshiba                 1 MBit x 9 70 nSec
                Matshushita             1 MBit x 9 70 nSec
                CDC Enterprises         1 MBit x 9 70 nSec
                Samsung (#KMM591000-7)  1 MBit x 9 70 nSec

     **NOTE**
     The following SIMM chips do not work in the Equity 386SX:
                IBM                     Panasonic
                Compaq                  NMBS

SOFTWARE:

Q29. What version of DOS is provided with the Equity 386SX?

A.   The Equity 386SX is packaged with MS-DOS version 4.01.

Q30. Is the Equity 386SX compatible with OS/2?

A.   Yes, since OS/2 is much more hardware-specific than MS-DOS, the Epson
     version of MS OS/2 is required.

Q31. Will it support Unix and/or Xenix? Which versions?

A.   The Equity 386SX has been tested w/ Santa Cruz Operations Xenix Rel. 2.1
     and IBM PC Xenix Vers. 1.
