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Author Topic: Are you buying an FPGA Amiga?  (Read 15002 times)

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Offline alexh

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Re: Are you buying an FPGA Amiga?
« on: March 28, 2011, 01:51:19 PM »
I never bought one, but I was loaned a MiniMig from ACube to help develop new cores. However they sent me one with a PIC without TinyBootloader and so I couldn't reprogram it. They said they would send a replacement PIC but never did and it has sat on the shelf in the office ever since.
 

Offline alexh

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Re: Are you buying an FPGA Amiga?
« Reply #1 on: March 28, 2011, 03:41:33 PM »
Quote from: mikej;625285
In theory, the FPGA clones are "identical" at a hardware level from the originals - they function at a gate level in exactly the same way as the original chips.
In theory yes. In practice no. But you know this ;)

Because the original schematics & netlists of the CBM chips have been lost over time. The FPGA contents are all re-interpretations by their various authors of how the Amiga hardware worked taken from the various specifications and from observations using logic analysers etc. Lots of information was undocumented and slowly comes out over time in the form of incompatabilities.

The guts of the original MiniMig especially does not work (buses etc.) how the original Amiga worked.
« Last Edit: March 28, 2011, 03:44:12 PM by alexh »