4 :
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( , , );
( , , ). (FDD Floppy Disk Drive) 3,5 12000 , IDE (Integrative Drive Electronics) 300000-500000 , SCSI 1 . . , , , 500000 (56 ), 1000 0,5%.
(, , ).
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1) . , , .
C (), ; n , .
C , ; n () ; m .
, (FDD Floppy Disk Drive) 3,5: CFDD = (18×512)×80×2 = 1474560 = 1,44 . 18 , 512 . , Boot- ( ) FAT ( ), 1457664 =1,39 .
. 5.1. .
LS-120 - 120 , JAZ JAZ2 1 2 . SyQuest 0,23 (EZFlyer) 1,5 (SyJet) , ORB 2,16 .
(HDD Hard Disk Drive) IDE 80 ( 5 ), SCSI , 10.
. IDE ATA (Advanced Technology Attachment AT) .
MLR - 25 , DDS 24 , DLT 20-40 , Mamonth - 120 .
CD-ROM: 650-700, DVD-ROM (Digital versatile disc ): 4,7-17 , 5,25 2´2,6 , 3,5 1,3 .
2) ( , -, internal transfer rate).
, . - , , . , , .. . , .
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dl , /; v , / ( 0,864 - 2,5 /); nk - (15-144).
F MLR 2 /, DDS 0,4-3 /, DLT 1,5-10 /.
t= 60/n , ; n , / (rpm rotation per minutes).
FDD FFDD ≈ 80 / (n = 300 rpm), LS-120 FLS-120 = 600 /, ZIP FZIP = 1,4 /, JAZ2 FJAZ2 = 8,7 /. SyQuest 2,4 (EZFlyer) 7 (SyJet) /, ORB 5 /.
HDD IDE FHDD = 15-60 / ( Ultra ATA-100 Ultra DMA-100 (Direct Memory Access), n = 5400-7200 rpm), SCSI 66 / (n = 7200-15000 rpm).
(CD-ROM Compact Disk ROM DVD-ROM) , 150 /. CD-ROM 40´ FCD-ROM 6 /. CD-ROM n = 7400-10400 ( 50´) rpm.
3,5 3,8 /, - 1,3 /.
3) (average seek time).
. : , , , .
l , (60-360 ); 1/3 , , .
t () ( - track to track seek), ; t () , . .. - .
FDD TFDD= 100 (t < 90 ), LS-120 TLS-120 = 70 , JAZ2 TJAZ2 = 16 , SyQuest 13,5 (EZFlyer) 11 (SyJet) , ORB 10 (), 12 ().
HDD IDE THDD = 8,5-12 (n = 5400-7200 rpm), SCSI 4-8 (n = 7200-15000 rpm).
CD-ROM TCD-ROM= 60-90 . DVD-ROM TDVD-ROM= 110-180 . 3,5 25 7 .
SLR TSLR= 45 .
4) . , .
d , . dl (/ bpi bit per inch). dq (1/ tpi tracks per inch). d = dl ´ dq.
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5.1.
QIC dl 96000 bpi (3800 /), dq 576 tpi (23 1/, FDD dl =17500 bpi (690 /) dq = 135 tpi (5,3 1/)
5.1.
, Gbpi2(/2) | , Gbpi2 (/2) | |
10 (16) | 20-50 (30-75) | |
30 (46) | 150-200 (230-300) |
() . ( ), - . : 0 1. () . , . .
: , , , -. - 3,5" (89 ) - 5,25" (133 ).
- (tracks). , , .
. 128, 256, 512 1024 , 512 . . - , .
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