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, "" : , . , 8 1 . , , . . 16- , , 216 = 64 . , , MS DOS 640 . 32-64 , .. (, , 1 = 1024 ).
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, , , . ( ), . , . , (, , !) . , , . , . , , . , . , ( ). , . , , .. , . , ( , , ), . . : -.
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. , , 486 , - . " cache ", ( , , , , , ). "" , , , . , , . , - . , ( ) , , : , . , - , , .
. , . , .
Chip Set - . , , "" . , , - , IBM PC . CMOS- - , . .
Chipset' , , . - OPTi495SLC, SiS471, UMC491, i82C437VX .. : , SiS471 - SiS85C471. ; - - (Neptun, Mercury, Triton, Viper), (ExpertChip, PC Chips).
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: , / , , , .. , , , ..
Basic Input/Output System - /, ( ROM BIOS). , DOS . BIOS , - , , /, Chipset . DOS/Windows BIOS , OS/2, UNIX, WinNT BIOS , .
(Main, System) BIOS, FDD, HDD, ; BIOS System Setup - . HDD ST-506 (MFM) SCSI BIOS ; - , ..
BIOS - Award Software, American Megatrends Inc. (AMI), - Phoenix Technology, Microid Research; Award BIOS 4.51G. (, IBM, Intel, Acer) BIOS' . BIOS - ; BIOS .
BIOS ; (Flash ROM), BIOS . BIOS, , ..
: 27xxxx - , 28xxxx 29xxxx - flash. 27xxxx - , "" ; - , .
Bus Mastering - , , ( , ). , (master) . / . Bus Mastering DMA, ; PC DMA, . Bus Mastering- , DMA- DMA- (16-, 16 , ..).
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. (RAM - Random Access Memory, ) : (SRAM - Static RAM) (DRAM - Dynamic RAM).
() - . - . , . (- ), ( ) . (-).
, , , . , ; - . ( - ) ; , RAS (Row Address Strobe - ), , - , CAS (Column Address Strobe - ). , . (- ), ( ) . .
SRAM DRAM - , , / - . , , . , , ; , .
FPM DRAM (Fast Page Mode DRAM - ) . , RAS , CAS, "CAS RAS". , , , - .
EDO (Extended Data Out - ) FPM, - . : , . 15% FPM . .
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BEDO (Burst EDO - EDO ) - EDO, , /. , , . BEDO - .
SDRAM (Synchronous DRAM - ) - , (FPM/EDO/BEDO). , SDRAM , . SDRAM . SDRAM , . SDRAM , FPM/EDO.
PB SRAM (Pipelined Burst SRAM - ) - SRAM , .
- , , . , , - . , 28/32- DIP- SRAM (8k*8, 16k*8, 32k*8, 64k*8, 128k*8), 486 256 32k*8 64k*8 ( - (tag) ). 128k*8 , 32- , . PB SRAM 100- PQFP 32- 32k*32 64k*32 Pentuim.
, 30- SIMM 8- 286, 386SX 486SLC , 386DX, 486DLC 486 - . 72- SIMM 32- 486 , Pentium Pentium Pro - . 168- DIMM 64- Pentium Pentium Pro . , (Interleave - ).
. (-7 -70, -15 -150), "-15" "-20" . - , 70 EDO DRAM, 50, 60 - 45, , - 70 60 . PB SRAM: 6 12, 7 - 15. SDRAM (10 12 ).
; ( ) / ( ).
:
61256 - 32k*8 (256 , 32 )
62512 - 64k*8 (512 , 64 )
32C32 - 32k*32 (1 , 128 )
32C64 - 64k*32 (2 , 256 )
:
41256 - 256k*1 (256 , 32 )
44256, 81C4256 - 256k*4 (1 , 128 )
411000, 81C1000 - 1M*1 (1 , 128 )
441000, 814400 - 1M*4 (4 , 512 )
41C4000 - 4M*4, (16 , 2 )
MT4C16257 - 256k*16 (4 , 512 )
MT4LC16M4A7 - 16M*8 (128 , 16 )
MT4LC2M8E7 - 2M*8 (16 , 2 , EDO)
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MT4C16270 - 256k*16 (4 , 512 , EDO)
EDO ( ) "" : , 53C400 - DRAM, 53C408 - EDO DRAM.
DIP, SIP, SIPP, SIMM, DIMM, CELP, COAST.
DIP (Dual In line Package - ) - , XT AT, - -. SIP (Single In line Package - ) - , . SIPP (Single In line Pinned Package - ) - , DIP/SIP; AT.
SIMM (Single In line Memory Module - ) - , ; , , . SIMM , , .
DIMM (Dual In line Memory Module - ) - , SIMM, ( 2 x 84), . Apple P5 P6.
SIMM FPM/EDO/BEDO, DIMM - EDO/BEDO/SDRAM.
CELP (Card Egde Low Profile - ) - -, SRAM () PB SRAM (). 72- SIMM, 256 512 . - COAST (Cache On A STick - " ").
, , (Parity) - SIMM 9- 36- ( ). , ( ). , - , , .
: , 30- SIMM - , ( - ), - ( ). 72- SIMM , - . 2, 4 8 .
- -, . , ; , , "" - .
72- SIMM PD (Presence Detect - ), 16 . PD "Brand name"- ( ). " ", SIMM, PD.
DIMM, JEDEC, PD (Serial EEPROM) Serial Presence Detect (SPD). 8- , DIMM, . chiset' 440LX/BX SPD . SPD, - DIMM , JEDEC.
Cache () . - . , , . , ( Write Through - ), ( Write Back - ). , , , (Delayed Write) - ; . , .
Write Back , .
, (), , (tag), (, , ..). : (direct mapped), ( ), n- (n-way associative), . , ; 4- .
Shadow Memory. . 640 1 (A0000-FFFFF) "", . , F0000-FFFFF , BIOS, C0000-C7FFF - (-BIOS), .. - Shadow , , "" ; . / . , ( BIOS ). -BIOS ..
Chiset , ( ). UMB- MS DOS -BIOS (, S_FONT).
Memory Relocation. (640 - 1 ) (Extended) . IBM PC 640 - , 384 . , , 384 . Chiset' Shadow Memory, (Neat, OPTi495, SiS471 ..) p , p p . Chipset' Shadow , - 384 ( Shadow).
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3. . (SIMM, DIMM, ), .
4. . (ISA, VLB, PCI, AGP, ..), . . 3.
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SIMM | DIMM | ISA | PCI | AGP |
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15. IntelTM.
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20. Memory Relocation?
21. Shadow Memory?
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23. DIP, SIP, SIPP, SIMM, DIMM, CELP, COAST?
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25. BIOS ?