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    AST RESEARCH, INC.            TECHNICAL BULLETIN # 1029                12-7-94

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                PREMMIA GX / MAYNARD ELECTRONICS MODEL 525Q SCSI TAPE UNIT

    PROBLEM:        With Premmia GX powered on and external SCSI tape drive
                    powered off, the drive's power and activity LEDs are lit.
                    There are no functional issues involved.

    CAUSE:          The Maynard Electronics (owned by Conner Peripherals, INC.)
                    Model 525Q SCSI tape unit draws a small amount of power from
                    pin 26 on the SCSI-2 connector while the tape unit is turned
                    off.  This causes the unit's power and drive activity LEDs to
                    light.  The power is supplied by the Premmia GX because it is
                    a requirement of the SCSI-2 specification.  This pin normally
                    provides power for terminators, even when the external device
                    at the end of the SCSI cable is powered off.  The SCSI bus
                    must be terminated at all times to ensure proper operation and
                    data integrity.

    SYSTEMS
    AFFECTED:           AST
                    PART NUMBER      DESCRIPTION

                    501457-XXX      PREMMIA GX P/90
                    501522-XXX      PREMMIA GX P/100

    SOLUTION:       To avoid drive LEDs misleading illumination, power on the
                    drive whenever the Premmia GX is powered on.