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[MiNT] AB040 memory layout
Hi,
perhaps you would be interested in a memory layout of an Afterburner040
- it could help people that are writting 68040/60 MMU support for
FreeMiNT:
~# /c/f/source/ass/log2phys.prg
$0E00000 => $1000000
$1000000 => $1094000
$1400000 => $1494000
$1800000 => $1894000
$1C00000 => $1C94000
$2000000 => $3094000
$2400000 => $3494000
$2800000 => $3894000
$2C00000 => $3C94000
$3000000 => $4094000
$3400000 => $4494000
$3800000 => $4894000
$3C00000 => $4C94000
The left column are logical and the right one are physical addresses.
First line shows that ROM has been copied into FastRAM (so called
FastROM). Then you can see there are two SIMMs in my machine - a 16 MB
SIMM in the first slot (physical memory window $1000000-$2FFFFFF) and a
32 MB SIMM in the second slot (physical memory window
$3000000-$4FFFFFF). The Doug's MC68040 Toolkit concatenated the two
physical blocks of memory into one contiguous block of memory that
begins at standard $1000000 (even if the actual physical addresses are
somewhere else). The MMU tree itself is hidden in FastRAM at $1082000.
Petr
--
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