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Amigo - Amiga 1000, in Verilog 2001, from schematic

Copyright 2010, Jason S. McMullan

The aim of the Amigo is to create a schematic-level
capture of the digital components of the 
Commodore Amiga 1000.

My personal reason for this project is to have a
functional Verilog simulation that can be used to:

* Validate emulators
* Convert into FPGA (a la Minimig)
* Assist in debugging old Amiga hardware
* Regenerate the Amiga 1000 schematic from Verilog

The last point seems to be the most important for me.
All of the Amiga 1000 schematics I have been able
to obtain online are very blurry, almost to the point
of unreadability. 

My hope is that the 'Amigo' will be able to be used
to generate a faithful and readable schematic one day.

- Jason S. McMullan

====

Progress so far:

* Selectable Wishbone cores for emulating the Motorola 68000

  - ao68000 (from OpenCores)
  	- True Motorola 68000 emulation, but
  	  Icarus Verilog 0.9 appears to hate it.

  - ucore (from OpenCores)
  	- MIPS32 core, which I am using for debugging
  	  under Icarus.

  - Any other Wishbone complaint 32-bit CPU core should be
    pluggable, via the 'Motorola_16_to_w32.v' module and
    a small amount of glue logic for interrupts.

* Amiga 1000 Daughterboard logic appears to be complete
  - $E00000 mirror of $F80000 does not exist, could be
    due to erroneous PAL logic. Will verify against my
    reference hardware.

Things to do:

* Create wrappers for Minimig's OCS cores (Paula, Agnus, Denise),
  to leverage the Minimig work for Amigo.

* Decide upon (for REAL!) whether to make the first pass of the
  Amigo 1000 a Rev A or a Rev C machine.
  - This affects mostly the part numbering (ie U6U or U6S for the
    M68000, etc).
  - It is most likely I will be doing a Rev A, as that appears to
    be what I have as my reference hardware.

* Finish out the Amigo capture, including pullup resistors, ferrite
  beads, etc.

* Decide what to do about the analog components (ie RGB to NTSC
  conversion circuity). Icarus Verlog doesn't (as of 0.9.x)
  support Verilog-AMS, so I may have to put that off.