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    AST RESEARCH, INC.          TECHNICAL BULLETIN # 1007                  11-2-94

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                           PREMMIA LX AND CHINON FLOPPY DRIVES

    PROBLEM:        Chinon floppy drive FR506 fails in the Premmia LX system.  The
                    following error message appears on the screen, when the drive
                    is not recognized by the system BIOS during power on:

                        "A: Drive Error" or "B: Drive error"

                    depending on the drive accessed.

    CAUSE:          For FCC compliance, the Premmia LX has 33 Ohm series resistors
                    on most floppy signal lines.  Chinon drives use TTL-compatible
                    150 Ohm pullups on some of the signal lines.  This combination
                    prevents active low signals from going below one volt.

    SYSTEMS
    AFFECTED:           AST
                    PART NUMBER      DESCRIPTION

                    501288-XXX      PREMMIA LX P/60
                    501289-XXX      PREMMIA LX P/66

    SOLUTION:       At this time AST does not support floppy disk drives requiring
                    150 Ohm pullups on the Premmia LX systems.  Use newer drive
                    types that use 1000 Ohm pullups, such as TEAC.