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Section 7 Cache
Rev. 4.00 Sep. 14, 2005 Page 181 of 982
REJ09B0023-0400
Data Array: Holds a 16-byte instruction or data. Entries are registered in the cache in line units
(16 bytes). The data array is not initialized by a power-on or manual reset, standby mode, module
standby mode, and sleep mode.
LRU: With the 4-way set associative system, up to four instructions or data with the same entry
address (address bits 11 to 4) can be registered in the cache. When an entry is registered, LRU
shows which of the four ways it is recorded in. There are six LRU bits, controlled by hardware. A
least-recently-used (LRU) algorithm is used to select the way that has been least recently accessed.
Six LRU bits indicate the way to be replaced in case of a cache miss.
The relationship between LRU and way replacement is shown is table 7.3 when the cache lock
function is not used 1 concerning the case where the cache lock function is used, see section 7.2.2,
Cache Control Register 2 (CCR2). If a bit pattern other than those listed in table 7.3 is set in the
LRU bits by software, the cache will not function correctly. When modifying the LRU bits by
software, set one of the patterns listed in table 7.3.
The LRU bits are initialized to 000000 by a power-on reset and retaining the previous value by a
manual reset, standby mode, module standby mode, and sleep mode.
Table 7.3
LRU and Way Replacement
LRU (Bits 5 to 0)
Way to be Replaced
000000, 000100, 010100, 100000, 110000, 110100
3
000001, 000011, 001011, 100001, 101001, 101011
2
000110, 000111, 001111, 010110, 011110, 011111
1
111000, 111001, 111011, 111100, 111110, 111111
0
Содержание HD6417641
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Страница 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
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Страница 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Страница 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Страница 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Страница 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Страница 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Страница 500: ...Section 13 Direct Memory Access Controller DMAC Rev 4 00 Sep 14 2005 Page 450 of 982 REJ09B0023 0400...
Страница 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Страница 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Страница 734: ...Section 18 Multi Function Timer Pulse Unit MTU Rev 4 00 Sep 14 2005 Page 684 of 982 REJ09B0023 0400...
Страница 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Страница 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Страница 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Страница 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Страница 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
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