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Old 01 July 2014, 07:39   #133
FPGAmiga rulez!
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Join Date: Dec 2007
Location: South of France
Age: 45
Posts: 155
Originally Posted by JimDrew View Post
Yes, Mike is a bit nutty when it comes to direct comparisons to the hardware, shaving chips, x-raying dies, etc.

There are a LOT of details that I discovered about Paula that are well beyond the patent descriptions, and the code above will not emulate Paula fully. You are missing several key elements, and will be missing more when you add the writing support. The DMA integration is one of the biggest problems, and there is of course the GCR module that everyone misses.
Right, the PRECOMP is tricky in the write support.
GCR is not really used (maybe on some write protected games ? and if you want to read C64 disks ?).
For the DMA, I have a 3-word FIFO and the famous DMAL one-wire protocol between Paula and Agnus.
There is also the early read cycle for DMA Disk write and Blitter destination.
I guess you were refferring to that part ? The Minimig totally missed this point with its one-clock DMA cycle.



Last edited by FrenchShark; 01 July 2014 at 08:10.
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