I/O Interfacing :: x86, ISA Bus

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I/O Interfacing x86, ISA Bus
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Topics

• Basic Interfacing
• Diagram
• ISA Bus
• Timing Diagram

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Basic Diagram
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8088 Demultiplexed Bus Configuration
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?????????????????????

• ????? I/O Map ??? Microprocessor ??? ?.??????????
  I/O ???? ????????????????????
• ????? Address ??? I/O ??????????????????
  ?????????? Decode
• ?????????????????????????????? Microprocessor
  ????????????????????????? ?
• ????????????????

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????? Address ????????? Logic expression
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(No Transcript)
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?????? I/O Write ??? Read
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Interfacing Example Basic I/O
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Basic System Timing
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RAM 6116
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TTLs 138, 139, 245, 374
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Interfacing Example RAM
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ISA Bus (A-B)
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ISA Bus (C-D)
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ISA Bus
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PC Ports
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Memory Map I/O

• ?????????????????????? I/O ????????
  ????????????????????????????? ????????????????????
  ? ???????? I/O
• ????????????????????? System Data Bus ??????????
  ?????????? I/O ?????????????????? ????????? 16
  bits
• ??????????????????????? ??????????????????????????
  ???????? ??? MREQ, WR, RD

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WireWrap
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WireWrap
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WireWrap Wrapping
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WireWrap