Section 3 Memory Management Unit (MMU)
SH7751 Group, SH7751R Group
Page 80 of 1128
R01UH0457EJ0301 Rev. 3.01
Sep 24, 2013
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SH: Share status bit
When 0, pages are not shared by processes.
When 1, pages are shared by processes.
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SZ: Page size bits
Specify the page size.
00: 1-Kbyte page
01: 4-Kbyte page
10: 64-Kbyte page
11: 1-Mbyte page
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V: Validity bit
Indicates whether the entry is valid.
0: Invalid
1: Valid
Cleared to 0 by a power-on reset.
Not affected by a manual reset.
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PPN: Physical page number
Upper 22 bits of the physical address.
With a 1-Kbyte page, PPN bits [28:10] are valid.
With a 4-Kbyte page, PPN bits [28:12] are valid.
With a 64-Kbyte page, PPN bits [28:16] are valid.
With a 1-Mbyte page, PPN bits [28:20] are valid.
The synonym problem must be taken into account when setting the PPN (see section 3.5.5,
Avoiding Synonym Problems).
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PR: Protection key data
2-bit data expressing the page access right as a code.
00: Can be read only, in privileged mode
01: Can be read and written in privileged mode
10: Can be read only, in privileged or user mode
11: Can be read and written in privileged mode or user mode