Author: Ragstaff (203-219-118-170-vic.tpgi.com.au)
Date: 06-20-2003 14:52
The 030 should be able to address 4gb of ram, seeing as it has a 32bit address bus
The 68000 has a 24bit address bus and should be able to access 16meg.
The ST and falcon had the upper two meg taken for a few things.... ROM, memory-mapped peripherals, etc. I think the falcon only had the peripherals in the same place to maintain some backwards compatibility with the the ST, otherwise, it could have been a lot different architecturally....
Only using 24bits of the address bus also made the falcon more compatible - an address points to the same piece of memory on an ST as it does on a Falcon. If the falcon used all 32 bits, then ST memory addresses would actually be "mirrored" in every 16meg chunk of Falcon memory = mess if compatibility is a priority.
I think that's right? anyone know better?
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