
                            EPSON AMERICA, INC.
                         Product Support Bulletin

           Subject: Equity 386SX PLUS Questions and Answers

Date: 4/3/91                                     PSB No:S-0131
Page(s): 1 of 9                              Originator: DS/MT


GENERAL:

Q1.  What microprocessor does the Equity 386SX PLUS use?

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

Q2.  At what speed does the Equity 386SX PLUS operate?

A.   The Equity 386SX PLUS operates at either 16MHz or 8MHz. The
     speed can be set by using the following keyboard commands:

                   CTRL ALT + = 16 MHz (High Speed)

                   CTRL ALT - = 8 MHz (Low Speed)

CTRL ALT * = Automatic speed mode set (This is when the floppy
disk drive is accessed.)

There is also an ESPEED utility that can be run at the command
prompt as follows:

ESPEED /H = Switch to high speed.

ESPEED /L = Switch to low speed.

ESPEED /A = Enables Automatic speed switching.

If you run ESPEED with no parameters the following message is
displayed:

Epson Speed control utility Version X.XX
Copyright (c) SEIKO EPSON CORP. 1990

                   Usage: ESPEED [/H] [/L] [/A]
                   /H = set high speed (no auto speed)
                   /L = set low speed (no auto speed)
                   /A = set auto speed


                                                               
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Q3.  What is the Auto Speed function?

A.   The Equity 386SX PLUS 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. See
     above procedure for setting the Auto Speed function.

Q4.  What BIOS does the Equity 386SX PLUS use?

A.   The Equity 386SX PLUS BIOS is written specifically for the
     computer by Seiko-Epson Corp.

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

A.   Yes, 80387SX support is available. The Equity 386SX PWS 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 PLUS use option cards that are
     available for the IBM PC/AT?

A.   The Equity 386SX PLUS uses an AT-compatible ISA (Industry
     Standard Architecture) bus 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 EQUITY
     series. There are 4 standard l/O expansion slots (one with
     8-bit bus and 3 with 1 6-bit bus). The 16-bit slots will 
     also accept most 8-bit compatible cards. The Equity 386SX PWS
     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 PLUS have a built-in 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 
     IRQ12 mouse or other device.


                                                               
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Q9.  Can any other Equity keyboards be used on this machine?

A.   Only the Equity Ie. Both the Equity Ie and the Equity 386SX
     PLUS use the PS/2-type mini-DIN connector. All other Equity 
     keyboards use the AT-type full-size DIN connector.

Q10. What is the logical assignment of Diskette Drives?

A.   When the Equity 386SX PLUS is configured with two diskette
     drives, it will boot from either diskette drive. If you boot 
     the system from a diskette in the second diskette drive, 
     normally the B drive, that drive becomes drive A and the 
     first diskette drive, normally drive A, becomes drive B. This
     assignment remains in affect until the system is reset with
     the reset switch, turned off, or is rebooted from the drive 
     currently designated as drive B or the AFDD.EXE utility on the 
     Reference Diskette is run (the use of AFDD is described later). 
     Therefore, the drive assignments can be controlled in two ways:

      1. Boot the computer from a diskette in the drive you want
         assigned as drive A.

      2. Run the AFDD program to reverse the current drive
         letter assignment.

     The current logical drive assignments remain in effect when
     the system is rebooted from the hard disk by pressing CTRL-ALT-DEL.
     The drive assignments are lost if the system is turned off or reset
     with the reset button.

     To use the AFDD utility, type AFDD at the command prompt and
     the following message appears on the screen:

                Reassign FDD utility Version X.XX
                Copyright (c) SEIKO EPSON CORP. 1989

                     New Assign         Present

                     Drive A: 1.2MB <== 1.44MB
                     Drive B: 1.44MB <== 1.2MB

                (S)et and Reboot, Any other key to Abort ?

     If you press S, the drive letters are switched and the system 
     reboots with the new assignments in effect. Pressing any other 
     key aborts the operation and returns to the command prompt.


                                                               
   
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     NOTE: The diskette drive types shown in AFDD message vary
           with the types of drives installed. If another type 
           of diskette drive is installed (360KB or 720KB), the 
           message is adjusted accordingly.

Q11. What terminal emulation boards are compatible with the 386SX
     PLUS?

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 386SX PLUS have a battery for the Real Time Clock?

A.   The 386SX PLUS uses the Dallas DS1287 RTC which incorporates
     an HD146818 compatible real-time clock with an internal battery.

Q13. What video adapter comes with the 386SX PLUS?

A.   The 386SX PLUS has built in VGA support that offers
     resolutions up to 800x600 when used with a multi-frequency 
     monitor.

Q14. Can the serial and parallel ports be disabled?

A.   Yes, the parallel and serial ports can be disabled by
     running the setup program on the reference diskette and 
     choosing DISABLE.

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

A.   The 386SX PLUS has 3 haH-height bays to support up to 3 
     half-height devices.
     There is no capability for a full-height device.

016. How many wait states does the 386SX PLUS have?

A.   At 16MHz, the system utilities 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 l/O 
     channel hold the READY signal low, thus wait states are 
     generated until the device can respond to the CPU.


                                                               
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Q17. Are the wait states user selectable?

A.   No, the 386SX PLUS 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 six (6) jumpers on the system board:

     System Board:

        Jumper 1: Password security enable/disable.
                        A: Disabled
                        B: Enabled

        Jumper 2: Onboard HDD interface enable/disable.
                        A: Enabled
                        B: Disabled

        Jumper 3: Internal Mouse port IRQ12.
                        A: Assigned to on board mouse port
                        B: IRQ12 assigned to bus expansion slot

        Jumper 4: Monitor type color/monochrome.
                        A: Color monitor
                        B: Mono monitor

        Jumper 5: Auto IOCHRDY enable/disable.
                        A: Disabled
                        B: Enabled

        Jumper 6: Onboard video enable/disable.
                        A: Enabled
                        B: Disabled
        NOTE: J6 is not present on early production units.


HARD DISK DRIVES:

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

A.   As a factory configuration, the 386SX PLUS is available with
     a 40MB, 3.5" hard disk (Conner CP-3044, 27ms access time). 
     This HDD offers a 1:1 interleave and uses an embedded controller
     with an IDE interface. When installing the 40MB drive, use 
     type 17. A 100MB option kit is also available.


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

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

Q21. Can the 386SX PLUS 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 J2 
     to position A. Other embedded controller AT-type drives can 
     also be used with the Host Interface.

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

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 as well as several ESDI drives. By providing 
     this support for 3rd party hard disk drives, the Equity SX PLUS
     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 386SX PLUS also has a User Definable setting that allows
     you to set up hard disk drives that are not supported by the 
     386SX PWS 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. This allows you to use hard
     drives much larger than 153MB.


FLOPPY DRIVES:

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

A.   The 386SX PLUS comes standard with either a 5.25" 1.2MB or
     3.5" 1.44MB floppy disk drive. There is built-in BIOS support 
     for industry standard 360KB and 1 .44MB, 3.5' haH-height floppy 
     disk drives as well as the 720KB, 3.5' floppy drive. All four drive
     sizes are available from Epson.

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

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

                                                               
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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.


MEMORY:

Q26. How much memory is standard on the 386SX PLUS?

A.   Currently there are two configurations 1 MB on the single
     FDD units and 2MB on factory-installed HDD units.

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

A.   You can add SIMMs (single in-line memory modules) for
     increased on-board memory by installing them onto the main 
     system board in the 386SX PLUS.
     With added SIMMs, the total amount of on-board memory in the
     computer must be one of the following: 2, 4, 6, 8, or 10 MB 
     (1 MB base) or 4, 6, 8, 10, 12 or 14MB (2MB base).

     There are 12 SIMM sockets inside the 386SX PLUS and 256KB
     and 1 MB 70ns SlMM's are used to upgrade memory in 2 MB 
     increments:

     SIMM Location: 386SX PLUS 2MB Base Unit


                6H 6L 5H 5L 4H 4L 3H 3L 2H 2L 1H 1L Total Memory
                ------------------------------------------------
                                   #  #  b  b  b  b 4MB
                             #  #  #  #  b  b  b  b 6MB
                       #  #  #  #  #  #  b  b  b  b 8MB
                 #  #  #  #  #  #  #  #  b  b  b  b 10MB
                 #  #  #  #  #  #  #  #  b  b  #  # 12MB
                 #  #  #  #  #  #  #  #  #  #  #  # 14MB

                Legend:
                b = Empty
                # = lMb x 1 x 9 SIMM's
                L = LOW Byte.
                H =HIGH Byte.

                Total includes the standard 2MB of System Memory


                                                               
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                SIMM Location: 386SX PLUS 1 FDD System

                6H 6L 5H 5L 4H 4L 3H 3L 2H 2L 1H 1L Total Memory
                ------------------------------------------------
                                        *  *  *  *  2MB
                                  #  #  *  *  *  *  4MB
                            #  #  #  #  *  *  *  *  6MB
                      #  #  #  #  #  #  *  *  *  *  8MB
                #  #  #  #  #  #  #  #  *  *  *  *  10MB

                Legend:
                * = 256 KB SIMM
                # = 1 MB SIMM

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

Q28. What SlMMs should be used when adding memory to the 386SX
     PLUS?

A.   Use the Epson lMB kit (A808231) or the 2MB kit (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
                Matsushita              1 MBit x 9 70 nSec
                CDC Enterprises         1 MBit x 9 70 nSec
                Samsung                 1 MBit x 9 70 nSec
                Acculogic               1 MBit x 9 70 nSec

       **NOTE**

        The following SIMM chips do not work in the 386SX PLUS:

                IBM             Panasonic
                Compaq          NMBS


SOFTWARE:

Q29. What version of MS-DOS is provided with the 386SX PLUS?

A.   MS-DOS is optional and the customer can choose between
     versions 3.30 and 4.01.


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

A.   Yes, Epson OS/2 1.0 and IBM OS/2 1.2 have been tested on the
     386SX PLUS.

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

A.   The Equity SX PLUS has been tested with Santa Cruz
     Operations Xenix 386 Rel. 2.3.2 and IBM PC Xenix Vers. 1.
