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B.1.5 Memory Protection
The ability to inhibit writes to physical memory was added. The sixteen 64 KB physical
memory blocks can be individually protected, and two of those blocks can additionally be
subdivided and protected at a granularity of 4 KB. When a write is attempted, a new
Priority 3 write-protection interrupt request is generated.
The write-protection can be enabled for the User mode only or for all modes (see
Figure B-1. Sample Memory Protection Layout
0x00000
0xFFFFF
0x40000
0x4FFFF
0x48000
WPHR = 0x0085
WPLR = 0x006C
WPSAR = 0x0004
WPSAHR = 0x0007
WPSALR = 0x00CC