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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.