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FPGA motherboard for 80386 CPU

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The 80386DX CPU had 132 pins:

    80386DX and 80386SX pinouts:
    http://www.rfwireless-world.com/images/80386-pin-diagram.jpg
    https://image.slidesharecdn.com/salientfeatursof80386-140822084001-phpapp02/95/salient-featurs-of-80386-14-638.jpg?cb=1408709884

    General architecture:
    http://www.nptel.ac.in/courses/Webcourse-contents/IISc-BANG/Microprocessors%20and%20Microcontrollers/pdf/Teacher_Slides/mod8/M8L1.pdf

Of these pins on the DX variant:

    32 pins -- data
    30 pins -- address
     4 pins -- byte enables in 32-bit writes
     1 pin  -- Read/write
     1 pin  -- Data/Control
     1 pin  -- Memory/IO
     1 pin  -- Bus mastering lock issued by CPU
     1 pin  -- Bus16 size (16-bit when asserted, normally 32-bit)
     1 pin  -- Next address (for pipelining)
     1 pin  -- Address valid signal
    --
    73 pins -- For basic I/O

     3 pins -- Math-coprocessor support
     1 pin  -- Ready (or Wait, for bus cycles to complete)
     2 pins -- Hold and Hold Acknowledge (for bus mastering)
     2 pins -- Interrupt and Non-masktable Interrupt
    --
     8 pins -- General coordination with external peripherals

     1 pin  -- Reset
     1 pin  -- Double-pumped clock
    --
     2 pins -- System input

The rest of the pins are unused, go to VSS or VCC.  This means that for a
full 80386 "motherboard" only 83 pins are required to fully support its
operation, 67 of which are address, data, and data type, leaving really
only 15 pins of complex operation for a state machine.

-----
Would anybody be able to help me create this 80386 motherboard using an
AMD Am386 CPU, which is a static CPU operating from 0 to 40 MHz?  I would
like to get it working with a single-step operation for design validation,
and then to begin ramping it up.

I figure I'll have an area of ROM which the CPU boots to load, which is a
tiny real mode program, which begins computing something that can be exam-
ined by the FPGA to test successful operation.  And then move on to more
complex operations, including a custom microkernel.

--
Rick C. Hodgin

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Thread

FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 07:35 -0800
  Re: FPGA motherboard for 80386 CPU rickman <gnuarm@gmail.com> - 2017-11-10 14:46 -0500
    Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 12:19 -0800
      Re: FPGA motherboard for 80386 CPU rickman <gnuarm@gmail.com> - 2017-11-10 16:11 -0500
        Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 14:14 -0800
          Re: FPGA motherboard for 80386 CPU rickman <gnuarm@gmail.com> - 2017-11-10 18:31 -0500
            Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 15:59 -0800
              Re: FPGA motherboard for 80386 CPU rickman <gnuarm@gmail.com> - 2017-11-10 22:15 -0500
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 20:16 -0800
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-11 10:43 -0800
      Re: FPGA motherboard for 80386 CPU lasselangwadtchristensen@gmail.com - 2017-11-10 13:15 -0800
        Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-10 14:02 -0800
          Re: FPGA motherboard for 80386 CPU lasselangwadtchristensen@gmail.com - 2017-11-13 08:28 -0800
            Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-13 08:49 -0800
              Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-13 09:33 -0800
              Re: FPGA motherboard for 80386 CPU lasselangwadtchristensen@gmail.com - 2017-11-13 11:47 -0800
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-13 11:54 -0800
                Re: FPGA motherboard for 80386 CPU lasselangwadtchristensen@gmail.com - 2017-11-13 12:06 -0800
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-11-13 12:15 -0800
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-21 01:33 -0800
                Re: FPGA motherboard for 80386 CPU Richard Damon <Richard@Damon-Family.org> - 2017-12-22 19:23 -0500
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-24 14:04 -0800
                Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-20 05:49 -0800
  Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-12 12:10 -0800
    Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-14 06:29 -0800
  Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-28 07:32 -0800
    Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-30 09:54 -0800
      Re: FPGA motherboard for 80386 CPU Richard Damon <Richard@Damon-Family.org> - 2017-12-30 15:18 -0500
        Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-31 00:20 -0800
          Re: FPGA motherboard for 80386 CPU Emilian Miron <emilian.miron@gmail.com> - 2017-12-31 07:20 -0800
            Re: FPGA motherboard for 80386 CPU "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-12-31 13:52 -0800

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