Quote:
Originally Posted by xanderbeanz
2. Why can the Amiga only address 2MB Chip RAM, not enough traces on the motherboard?
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As has already been said, no chips have been made with pins to control more than 2M.
Next up is the layout of the Amiga memory map: The original design only has a 16M address space. The first 512K was marked for chipram and then nothing before Zorro II starts at the 2M mark. The Zorro II space takes up 8M before you get into "Ranger"(slow - well not really, AFAIK the first A1000 expansions using this was actually proper Fastmem) memory space that is nearly another 2M in size. Assorted chips and ROM space then fills the rest.
So where do you put chipmem past 2M? You can eat out of the Zorro II space - that would max you out at near 12M chipmem.
However, the memory lists in an Amiga should support more than one region marked as chipmem so it should be possible to simply add another memory area (somewhere in 32-bit space) and the system would simply work except with more chipmem. This would need a way to detect and add this memory (a custom Kickstart preferably), and from a hw standpoint I would guess that you would design it as a single chipmem range but with the first 2M showing up twice in the address space.
You can already try having more chipmem with Minimig units and WinUAE AFAIK.