31 lines
1.2 KiB
Plaintext
31 lines
1.2 KiB
Plaintext
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AST RESEARCH, INC. TECHNICAL BULLETIN #0788 11-17-92
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=============================================================================
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AST 486 SYSTEMS WITH IBM'S 5250 EMULATION CARD
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If an IBM 5250 adapter is installed in an AST 80486-based system, errors may
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occur while accessing a high-density floppy drive. The DOS error generated
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is "FAILURE READING DRIVE X: ABORT, RETRY, IGNORE, FAIL", where "X" is the
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drive to which access is being attempted.
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The problem occurs because the IBM 5250 emulation card, which defaults to
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using IRQ 5, interferes with the operation of the floppy controller (at IRQ
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6), causing DMA overruns.
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To resolve this problem the following change needs to be made to the
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configuration of the PC Support program.
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In the STARTPCS batch file, at the line "E5250AH.COM" add the switch
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"/L7". The command line should read "E5250AH /L7". A capital "L" must
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be used.
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This effectively changes the IRQ used by the IBM5250 adapter board
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to 7. Note that no other device in the system should be using this
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interrupt.
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