EPROM (Erasable PROM ),
UV-EPROM (Ultra-Violet EPROM, ); EEPROM (ElectricalErasable PROM, ), -.
( ) (BIOS), (, ), (ESCD, EEPROM ).
PC ( BIOS ).
, . , , NVRAM (NonVolatileRandomAccessMemory).
5.5. ROM, FROM, EPROM
(ROM) ( 570 ). - .
(PROM) ( ) BIOS. , . , ( ), (, ).
(EPROM) BIOS , , .
EPROM , ( , ). . . . , ( ).
PC EPROM.
EPROM:
. .
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, , .
(5 ) Vpp ( ).
.
5.6. EEPROM -
. . EEPROM , . , , . EEPROM . EEPROM , . , , ( ) .
-, , EEPROM, . - : . (). - ( 30 % DRAM), , , ,
(. 1.15).
- . 1.16, , .
. 1.15. -
. 1.16. -
8- DIP PLCC: DIP-32, PLCC-32
- , . , , EPROM EEPROM. EPROM,
- (CacheMemory) (), ( ) . (cache) (). . - , , , . , . (cachedirectory) . , , : (, , ) ( Pentium 64 ).
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( )- :
, L1 Cache (Level I Cache), 1- , (Internal, Integrated) I486 , I386.
, L2 Cache (Level 2 Cache), 2- .
(External) , . PentiumPro Pentium II . . , I386, , ( ).
- , . , - (cachehit), -. , - (cachemiss), .
- (coherency) - , ( ), (busmaster) , (PCI, VLB, ISA...).
(cacheline) . , , , . . (valid) , (). , (. . ), (tag), (tag RAM).
(sectored) , , . , , . , .
- , , (WritePolicy). : WT (WriteThrough) WB (WriteBack).
WT ( ), , , .
WB . , , , (dirty), , . . . ( ) (clean) .
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-: (direct-mappedcache), (fullyassociativecache) - (set-associativecache).
- , , , .
- , (set). , , .
, . , () , . - , .