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MacOS 8.1
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Win98
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DOS
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This file was processed as: Mailbox/MIME Entity
(archive/mbox).
| Confidence | Program | Detection | Match Type | Support
|
|---|
| 100%
| dexvert
| Mailbox/MIME Entity (archive/mbox)
| magic
| Supported |
| 100%
| dexvert
| Internet Message Format (text/imf)
| magic
| Supported |
| 1%
| dexvert
| Text File (text/txt)
| fallback
| Supported |
| 100%
| file
| Mailbox text, 1st line "From coffin@ROCKY2.ROCKEFELLER.EDU Thu Mar 22 08:13:03 1990"
| default
| |
| 99%
| file
| data
| default
| |
| 100%
| TrID
| E-Mail message (Var. 2)
| default
| |
| 100%
| perlTextCheck
| Likely Text (Perl)
| default
| |
| 100%
| gt2
| Kopftext: 'From coffin'
| default (weak)
| |
| 100%
| detectItEasy
| Format: plain text[LF]
| default (weak)
| |
| 100%
| xdgMime
| application/mbox
| default
|
|
hex view+--------+-------------------------+-------------------------+--------+--------+
|00000000| 46 72 6f 6d 20 63 6f 66 | 66 69 6e 40 52 4f 43 4b |From cof|fin@ROCK|
|00000010| 59 32 2e 52 4f 43 4b 45 | 46 45 4c 4c 45 52 2e 45 |Y2.ROCKE|FELLER.E|
|00000020| 44 55 20 54 68 75 20 4d | 61 72 20 32 32 20 30 38 |DU Thu M|ar 22 08|
|00000030| 3a 31 33 3a 30 33 20 31 | 39 39 30 0a 46 6c 61 67 |:13:03 1|990.Flag|
|00000040| 73 3a 20 30 30 30 30 30 | 30 30 30 30 30 30 31 0a |s: 00000|0000001.|
|00000050| 52 65 74 75 72 6e 2d 50 | 61 74 68 3a 20 3c 63 6f |Return-P|ath: <co|
|00000060| 66 66 69 6e 40 52 4f 43 | 4b 59 32 2e 52 4f 43 4b |ffin@ROC|KY2.ROCK|
|00000070| 45 46 45 4c 4c 45 52 2e | 45 44 55 3e 0a 52 65 63 |EFELLER.|EDU>.Rec|
|00000080| 65 69 76 65 64 3a 20 66 | 72 6f 6d 20 52 4f 43 4b |eived: f|rom ROCK|
|00000090| 59 32 2e 52 4f 43 4b 45 | 46 45 4c 4c 45 52 2e 45 |Y2.ROCKE|FELLER.E|
|000000a0| 44 55 20 62 79 20 72 61 | 73 63 61 6c 2e 69 63 73 |DU by ra|scal.ics|
|000000b0| 2e 75 74 65 78 61 73 2e | 65 64 75 2e 20 28 34 2e |.utexas.|edu. (4.|
|000000c0| 30 2f 53 4d 49 2d 34 2e | 30 29 0a 09 69 64 20 41 |0/SMI-4.|0)..id A|
|000000d0| 41 32 38 34 33 32 3b 20 | 54 68 75 2c 20 32 32 20 |A28432; |Thu, 22 |
|000000e0| 4d 61 72 20 39 30 20 30 | 38 3a 31 32 3a 35 32 20 |Mar 90 0|8:12:52 |
|000000f0| 43 53 54 0a 52 65 63 65 | 69 76 65 64 3a 20 62 79 |CST.Rece|ived: by|
|00000100| 20 52 4f 43 4b 59 32 2e | 52 4f 43 4b 45 46 45 4c | ROCKY2.|ROCKEFEL|
|00000110| 4c 45 52 2e 45 44 55 20 | 28 35 2e 36 31 2f 31 2e |LER.EDU |(5.61/1.|
|00000120| 33 34 29 0a 09 69 64 20 | 41 41 31 34 37 39 37 3b |34)..id |AA14797;|
|00000130| 20 54 68 75 2c 20 32 32 | 20 4d 61 72 20 39 30 20 | Thu, 22| Mar 90 |
|00000140| 30 39 3a 31 33 3a 30 34 | 20 2d 30 35 30 30 0a 4d |09:13:04| -0500.M|
|00000150| 65 73 73 61 67 65 2d 49 | 64 3a 20 3c 39 30 30 33 |essage-I|d: <9003|
|00000160| 32 32 31 34 31 33 2e 41 | 41 31 34 37 39 37 40 52 |221413.A|A14797@R|
|00000170| 4f 43 4b 59 32 2e 52 4f | 43 4b 45 46 45 4c 4c 45 |OCKY2.RO|CKEFELLE|
|00000180| 52 2e 45 44 55 3e 0a 54 | 6f 3a 20 77 65 72 6e 65 |R.EDU>.T|o: werne|
|00000190| 72 40 72 61 73 63 61 6c | 2e 69 63 73 2e 75 74 65 |r@rascal|.ics.ute|
|000001a0| 78 61 73 2e 65 64 75 0a | 53 75 62 6a 65 63 74 3a |xas.edu.|Subject:|
|000001b0| 20 73 63 73 69 44 6f 63 | 73 2d 50 61 72 74 20 37 | scsiDoc|s-Part 7|
|000001c0| 20 6f 66 20 37 0a 44 61 | 74 65 3a 20 54 68 75 2c | of 7.Da|te: Thu,|
|000001d0| 20 32 32 20 4d 61 72 20 | 39 30 20 30 39 3a 31 32 | 22 Mar |90 09:12|
|000001e0| 3a 35 32 20 2d 30 35 30 | 30 0a 46 72 6f 6d 3a 20 |:52 -050|0.From: |
|000001f0| 63 6f 66 66 69 6e 40 52 | 4f 43 4b 59 32 2e 52 4f |coffin@R|OCKY2.RO|
|00000200| 43 4b 45 46 45 4c 4c 45 | 52 2e 45 44 55 0a 0a 0a |CKEFELLE|R.EDU...|
|00000210| 0a 2e 66 6f 20 41 70 70 | 65 6e 64 69 78 20 41 20 |..fo App|endix A |
|00000220| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00000230| 20 20 20 20 20 20 20 20 | 20 20 23 0a 2e 70 6e 20 | | #..pn |
|00000240| 31 37 34 0a 41 70 70 65 | 6e 64 69 78 65 73 20 20 |174.Appe|ndixes |
|00000250| 20 20 28 54 68 65 73 65 | 20 41 70 70 65 6e 64 69 | (These| Appendi|
|00000260| 78 65 73 20 61 72 65 20 | 6e 6f 74 20 70 61 72 74 |xes are |not part|
|00000270| 20 6f 66 20 41 6d 65 72 | 69 63 61 6e 20 4e 61 74 | of Amer|ican Nat|
|00000280| 69 6f 6e 61 6c 20 53 74 | 61 6e 64 61 72 64 20 0a |ional St|andard .|
|00000290| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 53 6d | | Sm|
|000002a0| 61 6c 6c 20 43 6f 6d 70 | 75 74 65 72 20 53 79 73 |all Comp|uter Sys|
|000002b0| 74 65 6d 20 49 6e 74 65 | 72 66 61 63 65 2c 20 58 |tem Inte|rface, X|
|000002c0| 33 2e 31 33 31 2e 31 39 | 38 5f 2c 20 62 75 74 20 |3.131.19|8_, but |
|000002d0| 61 72 65 20 69 6e 63 6c | 75 64 65 64 20 0a 20 20 |are incl|uded . |
|000002e0| 20 20 20 20 20 20 20 20 | 20 20 20 20 66 6f 72 20 | | for |
|000002f0| 69 6e 66 6f 72 6d 61 74 | 69 6f 6e 20 6f 6e 6c 79 |informat|ion only|
|00000300| 2e 29 0a 0a 02 41 70 70 | 65 6e 64 69 78 20 41 02 |.)...App|endix A.|
|00000310| 0a 0a 02 53 43 53 49 20 | 53 69 67 6e 61 6c 20 53 |...SCSI |Signal S|
|00000320| 65 71 75 65 6e 63 65 20 | 45 78 61 6d 70 6c 65 02 |equence |Example.|
|00000330| 0a 0a 54 68 69 73 20 61 | 70 70 65 6e 64 69 78 20 |..This a|ppendix |
|00000340| 69 73 20 69 6e 63 6c 75 | 64 65 64 20 74 6f 20 70 |is inclu|ded to p|
|00000350| 72 6f 76 69 64 65 20 61 | 6e 20 65 78 61 6d 70 6c |rovide a|n exampl|
|00000360| 65 20 6f 66 20 74 68 65 | 20 74 69 6d 69 6e 67 20 |e of the| timing |
|00000370| 6f 66 20 61 6e 20 53 43 | 53 49 20 0a 63 6f 6d 6d |of an SC|SI .comm|
|00000380| 61 6e 64 20 74 68 61 74 | 20 69 6e 63 6c 75 64 65 |and that| include|
|00000390| 73 20 6d 6f 73 74 20 6f | 66 20 74 68 65 20 53 43 |s most o|f the SC|
|000003a0| 53 49 20 62 75 73 20 70 | 68 61 73 65 73 20 28 46 |SI bus p|hases (F|
|000003b0| 69 67 75 72 65 20 41 31 | 29 2e 20 20 49 6e 20 74 |igure A1|). In t|
|000003c0| 68 69 73 20 0a 65 78 61 | 6d 70 6c 65 2c 20 74 68 |his .exa|mple, th|
|000003d0| 65 20 74 61 72 67 65 74 | 20 64 6f 65 73 20 6e 6f |e target| does no|
|000003e0| 74 20 64 69 73 63 6f 6e | 6e 65 63 74 20 66 72 6f |t discon|nect fro|
|000003f0| 6d 20 74 68 65 20 53 43 | 53 49 20 62 75 73 20 70 |m the SC|SI bus p|
|00000400| 72 69 6f 72 20 74 6f 20 | 63 6f 6d 70 6c 65 74 69 |rior to |completi|
|00000410| 6e 67 20 0a 74 68 65 20 | 63 6f 6d 6d 61 6e 64 2e |ng .the |command.|
|00000420| 0a 0a 20 20 54 68 65 20 | 66 6f 6c 6c 6f 77 69 6e |.. The |followin|
|00000430| 67 20 6e 6f 74 65 73 20 | 61 70 70 6c 79 20 74 6f |g notes |apply to|
|00000440| 20 46 69 67 75 72 65 20 | 41 31 3a 0a 0a 47 45 4e | Figure |A1:..GEN|
|00000450| 45 52 41 4c 20 4e 4f 54 | 45 3a 0a 0a 20 20 49 6e |ERAL NOT|E:.. In|
|00000460| 20 61 20 74 79 70 69 63 | 61 6c 20 73 79 73 74 65 | a typic|al syste|
|00000470| 6d 2c 20 74 68 65 20 63 | 6f 6d 70 75 74 65 72 27 |m, the c|omputer'|
|00000480| 73 20 68 6f 73 74 20 61 | 64 61 70 74 65 72 20 61 |s host a|dapter a|
|00000490| 63 74 73 20 61 73 20 74 | 68 65 20 22 69 6e 69 74 |cts as t|he "init|
|000004a0| 69 61 74 6f 72 22 20 61 | 6e 64 20 0a 74 68 65 20 |iator" a|nd .the |
|000004b0| 70 65 72 69 70 68 65 72 | 61 6c 20 64 65 76 69 63 |peripher|al devic|
|000004c0| 65 27 73 20 63 6f 6e 74 | 72 6f 6c 6c 65 72 20 61 |e's cont|roller a|
|000004d0| 63 74 73 20 61 73 20 74 | 68 65 20 22 74 61 72 67 |cts as t|he "targ|
|000004e0| 65 74 22 2e 20 20 49 6e | 20 67 65 6e 65 72 61 6c |et". In| general|
|000004f0| 2c 20 74 68 69 73 20 0a | 73 74 61 6e 64 61 72 64 |, this .|standard|
|00000500| 20 64 6f 65 73 20 6e 6f | 74 20 61 74 74 65 6d 70 | does no|t attemp|
|00000510| 74 20 74 6f 20 64 69 73 | 74 69 6e 67 75 69 73 68 |t to dis|tinguish|
|00000520| 20 62 65 74 77 65 65 6e | 20 61 20 63 6f 6d 70 75 | between| a compu|
|00000530| 74 65 72 20 61 6e 64 20 | 69 74 73 20 68 6f 73 74 |ter and |its host|
|00000540| 20 0a 61 64 61 70 74 65 | 72 2e 20 20 54 68 65 73 | .adapte|r. Thes|
|00000550| 65 20 66 75 6e 63 74 69 | 6f 6e 73 20 6d 61 79 20 |e functi|ons may |
|00000560| 62 65 20 73 65 70 61 72 | 61 74 65 20 6f 72 20 6d |be separ|ate or m|
|00000570| 65 72 67 65 64 2e 20 20 | 54 68 65 20 74 65 72 6d |erged. |The term|
|00000580| 20 22 69 6e 69 74 69 61 | 74 6f 72 22 20 0a 65 6e | "initia|tor" .en|
|00000590| 63 6f 6d 70 61 73 73 65 | 73 20 62 6f 74 68 2e 20 |compasse|s both. |
|000005a0| 20 53 69 6d 69 6c 61 72 | 6c 79 2c 20 74 68 65 20 | Similar|ly, the |
|000005b0| 74 65 72 6d 20 22 74 61 | 72 67 65 74 22 20 64 6f |term "ta|rget" do|
|000005c0| 65 73 20 6e 6f 74 20 64 | 69 73 74 69 6e 67 75 69 |es not d|istingui|
|000005d0| 73 68 20 62 65 74 77 65 | 65 6e 20 0a 74 68 65 20 |sh betwe|en .the |
|000005e0| 70 65 72 69 70 68 65 72 | 61 6c 20 64 65 76 69 63 |peripher|al devic|
|000005f0| 65 20 61 6e 64 20 69 74 | 73 20 63 6f 6e 74 72 6f |e and it|s contro|
|00000600| 6c 6c 65 72 2c 20 77 68 | 69 63 68 20 6d 61 79 20 |ller, wh|ich may |
|00000610| 62 65 20 73 65 70 61 72 | 61 74 65 20 6f 72 20 6d |be separ|ate or m|
|00000620| 65 72 67 65 64 2e 20 20 | 0a 54 68 65 20 74 65 72 |erged. |.The ter|
|00000630| 6d 20 22 53 43 53 49 20 | 64 65 76 69 63 65 22 20 |m "SCSI |device" |
|00000640| 72 65 66 65 72 73 20 74 | 6f 20 61 20 64 65 76 69 |refers t|o a devi|
|00000650| 63 65 20 74 68 61 74 20 | 6d 61 79 20 62 65 20 63 |ce that |may be c|
|00000660| 6f 6e 6e 65 63 74 65 64 | 20 74 6f 20 74 68 65 20 |onnected| to the |
|00000670| 53 43 53 49 20 0a 62 75 | 73 2e 20 20 41 6e 20 53 |SCSI .bu|s. An S|
|00000680| 43 53 49 20 64 65 76 69 | 63 65 20 6d 61 79 20 61 |CSI devi|ce may a|
|00000690| 63 74 20 61 73 20 69 6e | 20 74 68 65 20 69 6e 69 |ct as in| the ini|
|000006a0| 74 69 61 74 6f 72 20 72 | 6f 6c 65 2c 20 74 68 65 |tiator r|ole, the|
|000006b0| 20 74 61 72 67 65 74 20 | 72 6f 6c 65 2c 20 6f 72 | target |role, or|
|000006c0| 20 0a 62 6f 74 68 20 72 | 6f 6c 65 73 2e 0a 0a 54 | .both r|oles...T|
|000006d0| 49 4d 49 4e 47 20 4e 4f | 54 45 53 3a 0a 0a 02 42 |IMING NO|TES:...B|
|000006e0| 75 73 20 53 65 74 74 6c | 65 20 44 65 6c 61 79 2e |us Settl|e Delay.|
|000006f0| 02 20 20 54 68 65 20 6d | 69 6e 69 6d 75 6d 20 74 |. The m|inimum t|
|00000700| 69 6d 65 20 74 6f 20 77 | 61 69 74 20 66 6f 72 20 |ime to w|ait for |
|00000710| 74 68 65 20 53 43 53 49 | 20 62 75 73 20 74 6f 20 |the SCSI| bus to |
|00000720| 73 65 74 74 6c 65 20 61 | 66 74 65 72 20 0a 63 68 |settle a|fter .ch|
|00000730| 61 6e 67 69 6e 67 20 63 | 65 72 74 61 69 6e 20 63 |anging c|ertain c|
|00000740| 6f 6e 74 72 6f 6c 20 73 | 69 67 6e 61 6c 73 2e 0a |ontrol s|ignals..|
|00000750| 0a 02 42 75 73 20 46 72 | 65 65 20 44 65 6c 61 79 |..Bus Fr|ee Delay|
|00000760| 2e 02 20 20 54 68 65 20 | 6d 69 6e 69 6d 75 6d 20 |.. The |minimum |
|00000770| 74 69 6d 65 20 74 68 61 | 74 20 61 6e 20 53 43 53 |time tha|t an SCS|
|00000780| 49 20 64 65 76 69 63 65 | 20 6d 75 73 74 20 77 61 |I device| must wa|
|00000790| 69 74 20 66 72 6f 6d 20 | 69 74 73 20 0a 64 65 74 |it from |its .det|
|000007a0| 65 63 74 69 6f 6e 20 6f | 66 20 42 55 53 20 46 52 |ection o|f BUS FR|
|000007b0| 45 45 20 70 68 61 73 65 | 20 75 6e 74 69 6c 20 69 |EE phase| until i|
|000007c0| 74 20 6d 61 79 20 61 73 | 73 65 72 74 20 42 53 59 |t may as|sert BSY|
|000007d0| 20 61 6e 64 20 69 74 73 | 20 49 44 20 62 69 74 2e | and its| ID bit.|
|000007e0| 0a 0a 02 42 75 73 20 53 | 65 74 20 44 65 6c 61 79 |...Bus S|et Delay|
|000007f0| 2e 02 20 20 54 68 65 20 | 6d 61 78 69 6d 75 6d 20 |.. The |maximum |
|00000800| 74 69 6d 65 20 74 68 61 | 74 20 61 6e 20 53 43 53 |time tha|t an SCS|
|00000810| 49 20 64 65 76 69 63 65 | 20 6d 61 79 20 77 61 69 |I device| may wai|
|00000820| 74 20 74 6f 20 61 73 73 | 65 72 74 20 42 53 59 20 |t to ass|ert BSY |
|00000830| 0a 61 6e 64 20 69 74 73 | 20 49 44 20 62 69 74 20 |.and its| ID bit |
|00000840| 61 66 74 65 72 20 42 55 | 53 20 46 52 45 45 20 70 |after BU|S FREE p|
|00000850| 68 61 73 65 20 77 61 73 | 20 6c 61 73 74 20 64 65 |hase was| last de|
|00000860| 74 65 63 74 65 64 20 69 | 66 20 69 74 20 69 6e 74 |tected i|f it int|
|00000870| 65 6e 64 73 20 74 6f 20 | 0a 70 61 72 74 69 63 69 |ends to |.partici|
|00000880| 70 61 74 65 20 69 6e 20 | 74 68 65 20 41 52 42 49 |pate in |the ARBI|
|00000890| 54 52 41 54 49 4f 4e 20 | 70 68 61 73 65 2e 0a 0a |TRATION |phase...|
|000008a0| 02 42 75 73 20 43 6c 65 | 61 72 20 44 65 6c 61 79 |.Bus Cle|ar Delay|
|000008b0| 2e 02 20 20 54 68 65 20 | 6d 61 78 69 6d 75 6d 20 |.. The |maximum |
|000008c0| 74 69 6d 65 20 66 6f 72 | 20 61 6e 20 53 43 53 49 |time for| an SCSI|
|000008d0| 20 64 65 76 69 63 65 20 | 74 6f 20 73 74 6f 70 20 | device |to stop |
|000008e0| 64 72 69 76 69 6e 67 20 | 61 6c 6c 20 0a 73 69 67 |driving |all .sig|
|000008f0| 6e 61 6c 73 20 61 66 74 | 65 72 20 42 55 53 20 46 |nals aft|er BUS F|
|00000900| 52 45 45 20 70 68 61 73 | 65 20 69 73 20 64 65 74 |REE phas|e is det|
|00000910| 65 63 74 65 64 2c 20 61 | 66 74 65 72 20 53 45 4c |ected, a|fter SEL|
|00000920| 20 69 73 20 72 65 63 65 | 69 76 65 64 20 64 75 72 | is rece|ived dur|
|00000930| 69 6e 67 20 0a 41 52 42 | 49 54 52 41 54 49 4f 4e |ing .ARB|ITRATION|
|00000940| 20 70 68 61 73 65 2c 20 | 6f 72 20 61 66 74 65 72 | phase, |or after|
|00000950| 20 52 53 54 20 62 65 63 | 6f 6d 65 73 20 74 72 75 | RST bec|omes tru|
|00000960| 65 2e 0a 0a 02 41 72 62 | 69 74 72 61 74 69 6f 6e |e....Arb|itration|
|00000970| 20 44 65 6c 61 79 2e 02 | 20 20 54 68 65 20 6d 69 | Delay..| The mi|
|00000980| 6e 69 6d 75 6d 20 74 69 | 6d 65 20 74 68 61 74 20 |nimum ti|me that |
|00000990| 61 6e 20 53 43 53 49 20 | 64 65 76 69 63 65 20 6d |an SCSI |device m|
|000009a0| 75 73 74 20 77 61 69 74 | 20 61 66 74 65 72 20 0a |ust wait| after .|
|000009b0| 61 73 73 65 72 74 69 6e | 67 20 42 53 59 20 66 6f |assertin|g BSY fo|
|000009c0| 72 20 61 72 62 69 74 72 | 61 74 69 6f 6e 20 75 6e |r arbitr|ation un|
|000009d0| 74 69 6c 20 69 74 20 6d | 61 79 20 65 78 61 6d 69 |til it m|ay exami|
|000009e0| 6e 65 20 74 68 65 20 44 | 41 54 41 20 42 55 53 20 |ne the D|ATA BUS |
|000009f0| 74 6f 20 64 65 74 65 72 | 6d 69 6e 65 20 0a 77 68 |to deter|mine .wh|
|00000a00| 65 74 68 65 72 20 69 74 | 20 77 6f 6e 2e 20 20 54 |ether it| won. T|
|00000a10| 68 65 72 65 20 69 73 20 | 6e 6f 20 6d 61 78 69 6d |here is |no maxim|
|00000a20| 75 6d 20 74 69 6d 65 2e | 0a 2e 70 61 0a 0a 2e 2e |um time.|..pa....|
|00000a30| 20 46 69 67 75 72 65 20 | 41 31 20 67 6f 65 73 20 | Figure |A1 goes |
|00000a40| 68 65 72 65 2e 0a 2e 70 | 61 0a 0a 44 41 54 41 20 |here...p|a..DATA |
|00000a50| 42 55 53 20 4e 4f 54 45 | 53 3a 0a 0a 20 20 28 31 |BUS NOTE|S:.. (1|
|00000a60| 29 20 20 44 42 28 37 29 | 20 69 73 20 74 68 65 20 |) DB(7)| is the |
|00000a70| 6d 6f 73 74 20 73 69 67 | 6e 69 66 69 63 61 6e 74 |most sig|nificant|
|00000a80| 20 62 69 74 2e 0a 0a 20 | 20 28 32 29 20 20 44 42 | bit... | (2) DB|
|00000a90| 28 37 29 20 69 73 20 74 | 68 65 20 68 69 67 68 65 |(7) is t|he highe|
|00000aa0| 73 74 20 70 72 69 6f 72 | 69 74 79 20 61 72 62 69 |st prior|ity arbi|
|00000ab0| 74 72 61 74 69 6f 6e 20 | 62 69 74 2e 0a 0a 20 20 |tration |bit... |
|00000ac0| 28 33 29 20 20 44 42 28 | 50 29 20 69 73 20 74 68 |(3) DB(|P) is th|
|00000ad0| 65 20 64 61 74 61 20 70 | 61 72 69 74 79 20 62 69 |e data p|arity bi|
|00000ae0| 74 20 28 6f 64 64 29 2e | 20 20 50 61 72 69 74 79 |t (odd).| Parity|
|00000af0| 20 69 73 20 6e 6f 74 20 | 76 61 6c 69 64 20 64 75 | is not |valid du|
|00000b00| 72 69 6e 67 20 74 68 65 | 20 0a 41 52 42 49 54 52 |ring the| .ARBITR|
|00000b10| 41 54 49 4f 4e 20 70 68 | 61 73 65 2e 20 20 55 73 |ATION ph|ase. Us|
|00000b20| 65 20 6f 66 20 70 61 72 | 69 74 79 20 69 73 20 61 |e of par|ity is a|
|00000b30| 20 73 79 73 74 65 6d 20 | 6f 70 74 69 6f 6e 20 28 | system |option (|
|00000b40| 69 2e 65 2e 2c 20 61 20 | 73 79 73 74 65 6d 20 69 |i.e., a |system i|
|00000b50| 73 20 0a 63 6f 6e 66 69 | 67 75 72 65 64 20 73 6f |s .confi|gured so|
|00000b60| 20 74 68 61 74 20 61 6c | 6c 20 53 43 53 49 20 64 | that al|l SCSI d|
|00000b70| 65 76 69 63 65 73 20 6f | 6e 20 61 20 62 75 73 20 |evices o|n a bus |
|00000b80| 67 65 6e 65 72 61 74 65 | 20 70 61 72 69 74 79 20 |generate| parity |
|00000b90| 61 6e 64 20 68 61 76 65 | 20 70 61 72 69 74 79 20 |and have| parity |
|00000ba0| 0a 64 65 74 65 63 74 69 | 6f 6e 20 65 6e 61 62 6c |.detecti|on enabl|
|00000bb0| 65 64 2c 20 6f 72 20 61 | 6c 6c 20 53 43 53 49 20 |ed, or a|ll SCSI |
|00000bc0| 64 65 76 69 63 65 73 20 | 68 61 76 65 20 70 61 72 |devices |have par|
|00000bd0| 69 74 79 20 64 65 74 65 | 63 74 69 6f 6e 20 64 69 |ity dete|ction di|
|00000be0| 73 61 62 6c 65 64 20 6f | 72 20 6e 6f 74 20 0a 69 |sabled o|r not .i|
|00000bf0| 6d 70 6c 65 6d 65 6e 74 | 65 64 29 2e 0a 0a 42 55 |mplement|ed)...BU|
|00000c00| 53 20 50 48 41 53 45 20 | 4e 4f 54 45 53 3a 0a 0a |S PHASE |NOTES:..|
|00000c10| 02 42 55 53 20 46 52 45 | 45 20 70 68 61 73 65 2e |.BUS FRE|E phase.|
|00000c20| 02 20 20 42 55 53 20 46 | 52 45 45 20 70 68 61 73 |. BUS F|REE phas|
|00000c30| 65 20 62 65 67 69 6e 73 | 20 77 68 65 6e 20 53 45 |e begins| when SE|
|00000c40| 4c 20 61 6e 64 20 42 53 | 59 20 61 72 65 20 62 6f |L and BS|Y are bo|
|00000c50| 74 68 20 63 6f 6e 74 69 | 6e 75 6f 75 73 6c 79 20 |th conti|nuously |
|00000c60| 0a 66 61 6c 73 65 20 66 | 6f 72 20 61 20 62 75 73 |.false f|or a bus|
|00000c70| 20 73 65 74 74 6c 65 20 | 64 65 6c 61 79 2e 20 20 | settle |delay. |
|00000c80| 49 74 20 65 6e 64 73 20 | 77 68 65 6e 20 53 45 4c |It ends |when SEL|
|00000c90| 20 6f 72 20 42 53 59 20 | 62 65 63 6f 6d 65 73 20 | or BSY |becomes |
|00000ca0| 74 72 75 65 2e 0a 0a 02 | 41 52 42 49 54 52 41 54 |true....|ARBITRAT|
|00000cb0| 49 4f 4e 20 70 68 61 73 | 65 2e 02 20 20 49 6d 70 |ION phas|e.. Imp|
|00000cc0| 6c 65 6d 65 6e 74 61 74 | 69 6f 6e 20 6f 66 20 74 |lementat|ion of t|
|00000cd0| 68 69 73 20 70 68 61 73 | 65 20 69 73 20 6f 70 74 |his phas|e is opt|
|00000ce0| 69 6f 6e 61 6c 2e 20 20 | 49 66 20 74 68 65 72 65 |ional. |If there|
|00000cf0| 20 69 73 20 0a 6d 6f 72 | 65 20 74 68 61 6e 20 6f | is .mor|e than o|
|00000d00| 6e 65 20 69 6e 69 74 69 | 61 74 6f 72 2c 20 74 68 |ne initi|ator, th|
|00000d10| 65 6e 20 61 6c 6c 20 69 | 6e 69 74 69 61 74 6f 72 |en all i|nitiator|
|00000d20| 73 20 6d 75 73 74 20 69 | 6d 70 6c 65 6d 65 6e 74 |s must i|mplement|
|00000d30| 20 74 68 69 73 20 70 68 | 61 73 65 2e 20 20 0a 54 | this ph|ase. .T|
|00000d40| 61 72 67 65 74 73 20 74 | 68 61 74 20 64 6f 20 6e |argets t|hat do n|
|00000d50| 6f 74 20 69 6d 70 6c 65 | 6d 65 6e 74 20 74 68 69 |ot imple|ment thi|
|00000d60| 73 20 70 68 61 73 65 20 | 63 61 6e 6e 6f 74 20 64 |s phase |cannot d|
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|00001c10| 20 69 73 20 66 61 6c 73 | 65 20 61 74 20 74 68 65 | is fals|e at the|
|00001c20| 20 69 6e 69 74 69 61 74 | 6f 72 2c 20 74 68 65 20 | initiat|or, the |
|00001c30| 69 6e 69 74 69 61 74 6f | 72 20 6e 65 67 61 74 65 |initiato|r negate|
|00001c40| 73 20 41 43 4b 2e 20 20 | 41 66 74 65 72 20 41 43 |s ACK. |After AC|
|00001c50| 4b 20 69 73 20 0a 66 61 | 6c 73 65 2c 20 74 68 65 |K is .fa|lse, the|
|00001c60| 20 74 61 72 67 65 74 20 | 6d 61 79 20 63 6f 6e 74 | target |may cont|
|00001c70| 69 6e 75 65 20 74 68 65 | 20 74 72 61 6e 73 66 65 |inue the| transfe|
|00001c80| 72 20 62 79 20 64 72 69 | 76 69 6e 67 20 74 68 65 |r by dri|ving the|
|00001c90| 20 44 41 54 41 20 42 55 | 53 20 61 6e 64 20 0a 61 | DATA BU|S and .a|
|00001ca0| 73 73 65 72 74 69 6e 67 | 20 52 45 51 20 61 73 20 |sserting| REQ as |
|00001cb0| 64 65 73 63 72 69 62 65 | 64 20 61 62 6f 76 65 2e |describe|d above.|
|00001cc0| 0a 0a 02 44 41 54 41 20 | 4f 55 54 20 70 68 61 73 |...DATA |OUT phas|
|00001cd0| 65 20 28 6e 6f 74 20 73 | 68 6f 77 6e 20 69 6e 20 |e (not s|hown in |
|00001ce0| 74 68 65 20 66 69 67 75 | 72 65 29 2e 02 20 20 54 |the figu|re).. T|
|00001cf0| 68 65 20 74 61 72 67 65 | 74 20 6e 65 67 61 74 65 |he targe|t negate|
|00001d00| 73 20 43 2f 44 2c 20 49 | 2f 4f 2c 20 61 6e 64 20 |s C/D, I|/O, and |
|00001d10| 0a 4d 53 47 20 66 6f 72 | 20 61 6c 6c 20 6f 66 20 |.MSG for| all of |
|00001d20| 74 68 65 20 62 79 74 65 | 73 20 74 72 61 6e 73 66 |the byte|s transf|
|00001d30| 65 72 72 65 64 20 64 75 | 72 69 6e 67 20 74 68 69 |erred du|ring thi|
|00001d40| 73 20 70 68 61 73 65 2e | 20 20 54 68 65 20 64 69 |s phase.| The di|
|00001d50| 72 65 63 74 69 6f 6e 20 | 6f 66 20 0a 74 72 61 6e |rection |of .tran|
|00001d60| 73 66 65 72 20 69 73 20 | 66 72 6f 6d 20 74 68 65 |sfer is |from the|
|00001d70| 20 69 6e 69 74 69 61 74 | 6f 72 20 74 6f 20 74 68 | initiat|or to th|
|00001d80| 65 20 74 61 72 67 65 74 | 2e 20 20 28 52 65 66 65 |e target|. (Refe|
|00001d90| 72 20 74 6f 20 74 68 65 | 20 68 61 6e 64 73 68 61 |r to the| handsha|
|00001da0| 6b 65 20 0a 70 72 6f 63 | 65 64 75 72 65 20 61 6e |ke .proc|edure an|
|00001db0| 64 20 74 68 65 20 74 69 | 6d 69 6e 67 20 63 68 61 |d the ti|ming cha|
|00001dc0| 72 74 20 66 6f 72 20 74 | 68 65 20 43 4f 4d 4d 41 |rt for t|he COMMA|
|00001dd0| 4e 44 20 70 68 61 73 65 | 2e 29 0a 0a 02 53 54 41 |ND phase|.)...STA|
|00001de0| 54 55 53 20 70 68 61 73 | 65 2e 02 20 20 54 68 65 |TUS phas|e.. The|
|00001df0| 20 74 61 72 67 65 74 20 | 61 73 73 65 72 74 73 20 | target |asserts |
|00001e00| 43 2f 44 20 61 6e 64 20 | 49 2f 4f 20 61 6e 64 20 |C/D and |I/O and |
|00001e10| 6e 65 67 61 74 65 73 20 | 4d 53 47 20 66 6f 72 20 |negates |MSG for |
|00001e20| 74 68 65 20 62 79 74 65 | 20 0a 74 72 61 6e 73 66 |the byte| .transf|
|00001e30| 65 72 72 65 64 20 64 75 | 72 69 6e 67 20 74 68 69 |erred du|ring thi|
|00001e40| 73 20 70 68 61 73 65 2e | 20 20 54 68 65 20 64 69 |s phase.| The di|
|00001e50| 72 65 63 74 69 6f 6e 20 | 6f 66 20 74 72 61 6e 73 |rection |of trans|
|00001e60| 66 65 72 20 69 73 20 66 | 72 6f 6d 20 74 68 65 20 |fer is f|rom the |
|00001e70| 74 61 72 67 65 74 20 0a | 74 6f 20 74 68 65 20 69 |target .|to the i|
|00001e80| 6e 69 74 69 61 74 6f 72 | 2e 20 20 28 52 65 66 65 |nitiator|. (Refe|
|00001e90| 72 20 74 6f 20 74 68 65 | 20 68 61 6e 64 73 68 61 |r to the| handsha|
|00001ea0| 6b 65 20 70 72 6f 63 65 | 64 75 72 65 20 61 6e 64 |ke proce|dure and|
|00001eb0| 20 74 68 65 20 74 69 6d | 69 6e 67 20 63 68 61 72 | the tim|ing char|
|00001ec0| 74 20 66 6f 72 20 0a 74 | 68 65 20 44 41 54 41 20 |t for .t|he DATA |
|00001ed0| 49 4e 20 70 68 61 73 65 | 2e 29 0a 0a 02 4d 45 53 |IN phase|.)...MES|
|00001ee0| 53 41 47 45 20 70 68 61 | 73 65 2e 02 20 20 54 68 |SAGE pha|se.. Th|
|00001ef0| 65 20 74 61 72 67 65 74 | 20 43 2f 44 2c 20 49 2f |e target| C/D, I/|
|00001f00| 4f 2c 20 61 6e 64 20 4d | 53 47 20 64 75 72 69 6e |O, and M|SG durin|
|00001f10| 67 20 74 68 65 20 62 79 | 74 65 20 74 72 61 6e 73 |g the by|te trans|
|00001f20| 66 65 72 72 65 64 20 0a | 64 75 72 69 6e 67 20 74 |ferred .|during t|
|00001f30| 68 69 73 20 70 68 61 73 | 65 2e 20 20 54 79 70 69 |his phas|e. Typi|
|00001f40| 63 61 6c 6c 79 2c 20 61 | 20 43 4f 4d 4d 41 4e 44 |cally, a| COMMAND|
|00001f50| 20 43 4f 4d 50 4c 45 54 | 45 20 6d 65 73 73 61 67 | COMPLET|E messag|
|00001f60| 65 20 77 6f 75 6c 64 20 | 62 65 20 73 65 6e 74 20 |e would |be sent |
|00001f70| 61 74 20 0a 74 68 69 73 | 20 70 6f 69 6e 74 2e 20 |at .this| point. |
|00001f80| 20 54 68 65 20 64 69 72 | 65 63 74 69 6f 6e 20 6f | The dir|ection o|
|00001f90| 66 20 74 72 61 6e 73 66 | 65 72 20 69 73 20 66 72 |f transf|er is fr|
|00001fa0| 6f 6d 20 74 68 65 20 74 | 61 72 67 65 74 20 74 6f |om the t|arget to|
|00001fb0| 20 74 68 65 20 69 6e 69 | 74 69 61 74 6f 72 2e 20 | the ini|tiator. |
|00001fc0| 20 0a 28 52 65 66 65 72 | 20 74 6f 20 74 68 65 20 | .(Refer| to the |
|00001fd0| 68 61 6e 64 73 68 61 6b | 65 20 70 72 6f 63 65 64 |handshak|e proced|
|00001fe0| 75 72 65 20 61 6e 64 20 | 74 68 65 20 74 69 6d 69 |ure and |the timi|
|00001ff0| 6e 67 20 63 68 61 72 74 | 20 66 6f 72 20 74 68 65 |ng chart| for the|
|00002000| 20 44 41 54 41 20 49 4e | 20 70 68 61 73 65 2e 29 | DATA IN| phase.)|
|00002010| 0a 0a 02 42 55 53 20 46 | 52 45 45 20 70 68 61 73 |...BUS F|REE phas|
|00002020| 65 2e 02 20 20 54 68 65 | 20 74 61 72 67 65 74 20 |e.. The| target |
|00002030| 72 65 74 75 72 6e 73 20 | 74 6f 20 42 55 53 20 46 |returns |to BUS F|
|00002040| 52 45 45 20 70 68 61 73 | 65 20 62 79 20 72 65 6c |REE phas|e by rel|
|00002050| 65 61 73 69 6e 67 20 42 | 53 59 2e 20 20 42 6f 74 |easing B|SY. Bot|
|00002060| 68 20 0a 0a 74 68 65 20 | 74 61 72 67 65 74 20 61 |h ..the |target a|
|00002070| 6e 64 20 74 68 65 20 69 | 6e 69 74 69 61 74 6f 72 |nd the i|nitiator|
|00002080| 20 72 65 6c 65 61 73 65 | 20 61 6c 6c 20 62 75 73 | release| all bus|
|00002090| 20 73 69 67 6e 61 6c 73 | 20 77 69 74 68 69 6e 20 | signals| within |
|000020a0| 61 20 62 75 73 20 63 6c | 65 61 72 20 64 65 6c 61 |a bus cl|ear dela|
|000020b0| 79 20 0a 61 66 74 65 72 | 20 42 53 59 20 69 73 20 |y .after| BSY is |
|000020c0| 63 6f 6e 74 69 6e 75 6f | 75 73 6c 79 20 66 61 6c |continuo|usly fal|
|000020d0| 73 65 20 66 6f 72 20 61 | 20 62 75 73 20 73 65 74 |se for a| bus set|
|000020e0| 74 6c 65 20 64 65 6c 61 | 79 2e 0a 2e 66 6f 20 41 |tle dela|y...fo A|
|000020f0| 70 70 65 6e 64 69 78 20 | 41 20 20 20 20 20 20 20 |ppendix |A |
|00002100| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002110| 20 20 31 37 36 2e 32 0a | 2e 70 61 0a 0a 1a 1a 1a | 176.2.|.pa.....|
|00002120| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00002130| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00002140| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00002150| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 0a 2e 70 6e 20 |........|.....pn |
|00002160| 31 37 37 0a 2e 66 6f 20 | 41 70 70 65 6e 64 69 78 |177..fo |Appendix|
|00002170| 20 42 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | B | |
|00002180| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 23 0a 02 | | #..|
|00002190| 41 70 70 65 6e 64 69 78 | 20 42 02 0a 0a 02 54 79 |Appendix| B....Ty|
|000021a0| 70 69 63 61 6c 20 42 75 | 73 20 50 68 61 73 65 20 |pical Bu|s Phase |
|000021b0| 53 65 71 75 65 6e 63 65 | 02 0a 0a 54 68 69 73 20 |Sequence|...This |
|000021c0| 61 70 70 65 6e 64 69 78 | 20 69 73 20 69 6e 63 6c |appendix| is incl|
|000021d0| 75 64 65 64 20 74 6f 20 | 70 72 6f 76 69 64 65 20 |uded to |provide |
|000021e0| 61 6e 20 65 78 61 6d 70 | 6c 65 20 6f 66 20 74 68 |an examp|le of th|
|000021f0| 65 20 53 43 53 49 20 62 | 75 73 20 70 68 61 73 65 |e SCSI b|us phase|
|00002200| 20 73 65 71 75 65 6e 63 | 65 20 0a 66 6f 72 20 61 | sequenc|e .for a|
|00002210| 20 74 79 70 69 63 61 6c | 20 52 45 41 44 20 63 6f | typical| READ co|
|00002220| 6d 6d 61 6e 64 20 28 54 | 61 62 6c 65 73 20 42 31 |mmand (T|ables B1|
|00002230| 20 61 6e 64 20 42 32 29 | 2e 20 20 49 6e 20 74 68 | and B2)|. In th|
|00002240| 69 73 20 65 78 61 6d 70 | 6c 65 2c 20 74 68 65 20 |is examp|le, the |
|00002250| 74 61 72 67 65 74 20 0a | 64 6f 65 73 20 6e 6f 74 |target .|does not|
|00002260| 20 64 69 73 63 6f 6e 6e | 65 63 74 20 66 72 6f 6d | disconn|ect from|
|00002270| 20 74 68 65 20 53 43 53 | 49 20 62 75 73 20 70 72 | the SCS|I bus pr|
|00002280| 69 6f 72 20 74 6f 20 63 | 6f 6d 70 6c 65 74 69 6e |ior to c|ompletin|
|00002290| 67 20 74 68 65 20 63 6f | 6d 6d 61 6e 64 2e 0a 0a |g the co|mmand...|
|000022a0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000022b0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000022c0| 20 20 20 02 54 61 62 6c | 65 20 42 31 02 0a 20 20 | .Tabl|e B1.. |
|000022d0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000022e0| 20 20 20 02 54 79 70 69 | 63 61 6c 20 52 45 41 44 | .Typi|cal READ|
|000022f0| 20 43 6f 6d 6d 61 6e 64 | 20 50 68 61 73 65 20 53 | Command| Phase S|
|00002300| 65 71 75 65 6e 63 65 02 | 0a 0a 3d 3d 3d 3d 3d 3d |equence.|..======|
|00002310| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002320| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002330| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002340| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002350| 3d 3d 3d 3d 3d 3d 3d 3d | 0a 20 20 20 20 20 20 20 |========|. |
|00002360| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002370| 20 20 20 20 20 20 20 20 | 20 20 20 20 53 69 67 6e | | Sign|
|00002380| 61 6c 73 0a 20 20 20 20 | 20 20 20 20 20 20 20 20 |als. | |
|00002390| 20 20 20 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d | -----|--------|
|000023a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000023b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000023c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000023d0| 2d 2d 0a 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |--. | |
|000023e0| 20 20 42 20 20 53 20 20 | 41 20 20 4d 20 20 43 20 | B S |A M C |
|000023f0| 20 49 20 20 52 20 20 41 | 20 20 52 20 20 20 20 44 | I R A| R D|
|00002400| 20 20 20 20 44 0a 20 20 | 20 20 20 20 20 20 20 20 | D. | |
|00002410| 20 20 20 20 20 53 20 20 | 45 20 20 54 20 20 53 20 | S |E T S |
|00002420| 20 2f 20 20 2f 20 20 45 | 20 20 43 20 20 53 20 20 | / / E| C S |
|00002430| 20 20 42 20 20 20 20 42 | 0a 42 75 73 20 50 68 61 | B B|.Bus Pha|
|00002440| 73 65 20 20 20 20 20 20 | 59 20 20 4c 20 20 4e 20 |se |Y L N |
|00002450| 20 47 20 20 44 20 20 4f | 20 20 51 20 20 4b 20 20 | G D O| Q K |
|00002460| 54 20 20 28 37 2d 30 29 | 20 28 50 29 20 20 20 20 |T (7-0)| (P) |
|00002470| 43 6f 6d 6d 65 6e 74 0a | 2d 2d 2d 2d 2d 2d 2d 2d |Comment.|--------|
|00002480| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00002490| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000024a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000024b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000024c0| 2d 2d 2d 2d 2d 2d 0a 42 | 55 53 20 46 52 45 45 20 |------.B|US FREE |
|000024d0| 20 20 20 20 20 20 2d 20 | 20 2d 20 20 2d 20 20 2d | - | - - -|
|000024e0| 20 20 2d 20 20 2d 20 20 | 2d 20 20 2d 20 20 2d 20 | - - |- - - |
|000024f0| 20 20 20 2d 20 20 20 20 | 2d 20 20 20 20 20 53 43 | - |- SC|
|00002500| 53 49 20 62 75 73 20 69 | 73 20 61 76 61 69 6c 61 |SI bus i|s availa|
|00002510| 62 6c 65 2e 20 0a 0a 41 | 52 42 49 54 52 41 54 49 |ble. ..A|RBITRATI|
|00002520| 4f 4e 20 20 20 20 31 20 | 20 2d 20 20 2d 20 20 2d |ON 1 | - - -|
|00002530| 20 20 2d 20 20 2d 20 20 | 2d 20 20 2d 20 20 2d 20 | - - |- - - |
|00002540| 20 20 20 49 44 20 20 20 | 58 20 20 20 20 20 49 6e | ID |X In|
|00002550| 69 74 69 61 74 6f 72 20 | 74 72 69 65 73 20 74 6f |itiator |tries to|
|00002560| 20 67 65 74 20 0a 20 20 | 20 20 20 22 20 20 20 20 | get . | " |
|00002570| 20 20 20 20 20 20 20 20 | 31 20 20 20 20 20 20 20 | |1 |
|00002580| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002590| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 74 68 65 | | the|
|000025a0| 20 53 43 53 49 20 62 75 | 73 2e 0a 0a 53 45 4c 45 | SCSI bu|s...SELE|
|000025b0| 43 54 49 4f 4e 20 20 20 | 20 20 20 31 20 20 31 20 |CTION | 1 1 |
|000025c0| 20 31 20 20 2d 20 20 2d | 20 20 2d 20 20 2d 20 20 | 1 - -| - - |
|000025d0| 30 20 20 2d 20 20 49 44 | 20 49 2c 54 20 56 20 20 |0 - ID| I,T V |
|000025e0| 20 20 20 49 6e 69 74 69 | 61 74 6f 72 20 68 61 73 | Initi|ator has|
|000025f0| 20 53 43 53 49 20 62 75 | 73 20 0a 20 20 20 20 20 | SCSI bu|s . |
|00002600| 22 20 20 20 20 20 20 20 | 20 20 2d 20 20 31 20 20 |" | - 1 |
|00002610| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002620| 20 20 20 20 20 49 44 20 | 49 2c 54 20 56 20 20 20 | ID |I,T V |
|00002630| 20 20 61 6e 64 20 73 65 | 6c 65 63 74 73 20 61 20 | and se|lects a |
|00002640| 74 61 72 67 65 74 2e 0a | 20 20 20 20 20 22 20 20 |target..| " |
|00002650| 20 20 20 20 20 20 20 31 | 20 20 31 20 20 20 20 20 | 1| 1 |
|00002660| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002670| 20 20 49 44 20 49 2c 54 | 20 56 20 20 20 20 20 41 | ID I,T| V A|
|00002680| 54 4e 20 69 73 20 6f 6e | 2e 20 0a 20 20 20 20 20 |TN is on|. . |
|00002690| 22 20 20 20 20 20 20 20 | 20 20 31 20 20 2d 20 20 |" | 1 - |
|000026a0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000026b0| 20 20 20 20 20 20 20 58 | 20 20 20 20 58 0a 0a 4d | X| X..M|
|000026c0| 45 53 53 41 47 45 20 4f | 55 54 20 20 20 20 31 20 |ESSAGE O|UT 1 |
|000026d0| 20 2d 20 20 31 20 20 31 | 20 20 31 20 20 30 20 20 | - 1 1| 1 0 |
|000026e0| 30 20 20 30 20 20 2d 20 | 20 20 20 58 20 20 20 20 |0 0 - | X |
|000026f0| 58 20 20 20 20 20 54 61 | 72 67 65 74 20 68 61 73 |X Ta|rget has|
|00002700| 20 63 6f 6e 74 72 6f 6c | 20 6f 66 0a 20 20 20 20 | control| of. |
|00002710| 20 22 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | " | |
|00002720| 20 31 20 20 20 20 20 20 | 20 20 20 20 20 31 20 20 | 1 | 1 |
|00002730| 30 20 20 20 20 20 20 20 | 58 20 20 20 20 58 20 20 |0 |X X |
|00002740| 20 20 20 74 68 65 20 62 | 75 73 20 61 6e 64 20 67 | the b|us and g|
|00002750| 65 74 73 20 74 68 65 20 | 0a 20 20 20 20 20 22 20 |ets the |. " |
|00002760| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 31 20 | | 1 |
|00002770| 20 20 20 20 20 20 20 20 | 20 20 31 20 20 30 20 20 | | 1 0 |
|00002780| 20 20 20 20 20 58 20 20 | 20 20 58 20 20 20 20 20 | X | X |
|00002790| 49 44 45 4e 54 49 46 59 | 20 6d 65 73 73 61 67 65 |IDENTIFY| message|
|000027a0| 20 66 72 6f 6d 0a 20 20 | 20 20 20 22 20 20 20 20 | from. | " |
|000027b0| 20 20 20 20 20 20 20 20 | 20 20 20 31 20 20 20 20 | | 1 |
|000027c0| 20 20 20 20 20 20 20 31 | 20 20 31 20 20 20 20 4d | 1| 1 M|
|000027d0| 65 73 73 61 67 65 20 56 | 20 20 20 20 20 74 68 65 |essage V| the|
|000027e0| 20 69 6e 69 74 69 61 74 | 6f 72 2e 20 0a 20 20 20 | initiat|or. . |
|000027f0| 20 20 22 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | " | |
|00002800| 20 20 31 20 20 20 20 20 | 20 20 20 20 20 20 30 20 | 1 | 0 |
|00002810| 20 31 20 20 20 20 20 20 | 20 58 20 20 20 20 58 0a | 1 | X X.|
|00002820| 20 20 20 20 20 22 20 20 | 20 20 20 20 20 20 20 20 | " | |
|00002830| 20 20 20 20 20 30 20 20 | 20 20 20 20 20 20 20 20 | 0 | |
|00002840| 20 30 20 20 30 20 20 20 | 20 20 20 20 58 20 20 20 | 0 0 | X |
|00002850| 20 58 0a 0a 43 4f 4d 4d | 41 4e 44 20 20 20 20 20 | X..COMM|AND |
|00002860| 20 20 20 31 20 20 2d 20 | 20 30 20 20 30 20 20 31 | 1 - | 0 0 1|
|00002870| 20 20 30 20 20 30 20 20 | 30 20 20 2d 20 20 20 20 | 0 0 |0 - |
|00002880| 58 20 20 20 20 58 20 20 | 20 20 20 54 61 72 67 65 |X X | Targe|
|00002890| 74 20 67 65 74 73 20 61 | 20 63 6f 6d 6d 61 6e 64 |t gets a| command|
|000028a0| 20 0a 20 20 20 20 20 22 | 20 20 20 20 20 20 20 20 | . "| |
|000028b0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000028c0| 20 20 20 31 20 20 30 20 | 20 20 20 20 20 20 58 20 | 1 0 | X |
|000028d0| 20 20 20 58 20 20 20 20 | 20 66 72 6f 6d 20 74 68 | X | from th|
|000028e0| 65 20 69 6e 69 74 69 61 | 74 6f 72 2e 20 0a 20 20 |e initia|tor. . |
|000028f0| 20 20 20 22 20 20 20 20 | 20 20 20 20 20 20 20 20 | " | |
|00002900| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 31 | | 1|
|00002910| 20 20 31 20 20 20 20 43 | 6f 6d 6d 61 6e 64 20 56 | 1 C|ommand V|
|00002920| 20 20 20 20 20 28 54 68 | 69 73 20 70 68 61 73 65 | (Th|is phase|
|00002930| 20 69 73 20 72 65 70 65 | 61 74 65 64 20 0a 20 20 | is repe|ated . |
|00002940| 20 20 20 22 20 20 20 20 | 20 20 20 20 20 20 20 20 | " | |
|00002950| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 30 | | 0|
|00002960| 20 20 31 20 20 20 20 20 | 20 20 58 20 20 20 20 58 | 1 | X X|
|00002970| 20 20 20 20 20 66 6f 72 | 20 65 61 63 68 20 62 79 | for| each by|
|00002980| 74 65 2e 29 0a 20 20 20 | 20 20 22 20 20 20 20 20 |te.). | " |
|00002990| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000029a0| 20 20 20 20 20 20 30 20 | 20 30 20 20 20 20 20 20 | 0 | 0 |
|000029b0| 20 58 20 20 20 20 58 0a | 3d 3d 3d 3d 3d 3d 3d 3d | X X.|========|
|000029c0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000029d0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000029e0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000029f0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002a00| 3d 3d 3d 3d 3d 3d 0a 2e | 70 61 0a 0a 20 20 20 20 |======..|pa.. |
|00002a10| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00002a20| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 02 | | .|
|00002a30| 54 61 62 6c 65 20 42 32 | 02 0a 20 20 20 20 20 20 |Table B2|.. |
|00002a40| 20 20 20 20 20 20 20 20 | 20 02 54 79 70 69 63 61 | | .Typica|
|00002a50| 6c 20 52 45 41 44 20 43 | 6f 6d 6d 61 6e 64 20 50 |l READ C|ommand P|
|00002a60| 68 61 73 65 20 53 65 71 | 75 65 6e 63 65 20 28 43 |hase Seq|uence (C|
|00002a70| 6f 6e 74 69 6e 75 65 64 | 29 02 0a 0a 3d 3d 3d 3d |ontinued|)...====|
|00002a80| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002a90| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002aa0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00002ab0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
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|00003080| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003090| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
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|00005520| 20 74 68 65 20 6f 70 65 | 72 61 74 69 6f 6e 20 69 | the ope|ration i|
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|00005550| 20 74 6f 20 75 74 69 6c | 69 7a 65 20 74 68 65 20 | to util|ize the |
|00005560| 64 61 74 61 20 74 72 61 | 6e 73 66 65 72 72 65 64 |data tra|nsferred|
|00005570| 20 69 6e 74 6f 20 74 68 | 65 20 64 61 74 61 20 0a | into th|e data .|
|00005580| 62 6c 6f 63 6b 2e 0a 0a | 02 43 33 2e 20 49 2f 4f |block...|.C3. I/O|
|00005590| 20 43 68 61 6e 6e 65 6c | 20 43 6f 6e 63 65 70 74 | Channel| Concept|
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|000055c0| 20 75 74 69 6c 69 7a 65 | 73 20 74 68 65 20 68 69 | utilize|s the hi|
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|00005620| 20 53 43 53 49 20 68 6f | 73 74 20 61 64 61 70 74 | SCSI ho|st adapt|
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|00005670| 20 6d 65 6d 6f 72 79 20 | 49 2f 4f 20 62 6c 6f 63 | memory |I/O bloc|
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|000056a0| 0a 0a 20 20 54 68 65 20 | 49 2f 4f 20 63 68 61 6e |.. The |I/O chan|
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|00005920| 61 73 20 74 68 65 20 73 | 61 76 69 6e 67 20 69 6e |as the s|aving in|
|00005930| 20 62 61 63 6b 70 6c 61 | 6e 65 20 63 61 72 64 20 | backpla|ne card |
|00005940| 73 6c 6f 74 73 2e 0a 0a | 20 20 49 6e 20 74 68 65 |slots...| In the|
|00005950| 20 52 45 41 44 20 63 6f | 6d 6d 61 6e 64 20 65 78 | READ co|mmand ex|
|00005960| 61 6d 70 6c 65 20 64 69 | 73 63 75 73 73 65 64 20 |ample di|scussed |
|00005970| 69 6e 20 53 65 63 74 69 | 6f 6e 20 43 32 2c 20 74 |in Secti|on C2, t|
|00005980| 68 65 20 49 2f 4f 20 63 | 68 61 6e 6e 65 6c 20 69 |he I/O c|hannel i|
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|000059c0| 4f 20 63 68 61 6e 6e 65 | 6c 20 61 20 63 6f 6d 6d |O channe|l a comm|
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|00005a00| 6d 6f 72 79 20 62 6c 6f | 63 6b 73 20 61 6e 64 20 |mory blo|cks and |
|00005a10| 74 68 65 20 53 43 53 49 | 20 70 65 72 69 70 68 65 |the SCSI| periphe|
|00005a20| 72 61 6c 20 61 64 64 72 | 65 73 73 2e 20 20 54 68 |ral addr|ess. Th|
|00005a30| 69 73 20 0a 65 73 74 61 | 62 6c 69 73 68 65 73 20 |is .esta|blishes |
|00005a40| 61 20 74 68 72 65 61 64 | 20 62 65 74 77 65 65 6e |a thread| between|
|00005a50| 20 74 68 65 20 68 6f 73 | 74 20 61 64 61 70 74 65 | the hos|t adapte|
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|00005a70| 2f 4f 20 6d 65 6d 6f 72 | 79 20 62 6c 6f 63 6b 73 |/O memor|y blocks|
|00005a80| 2e 20 20 0a 54 68 65 20 | 49 2f 4f 20 63 68 61 6e |. .The |I/O chan|
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|00005aa0| 20 73 75 62 63 68 61 6e | 6e 65 6c 20 74 68 61 74 | subchan|nel that|
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|00005ac0| 20 74 61 73 6b 20 6f 66 | 20 6d 61 6e 61 67 69 6e | task of| managin|
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|00005ae0| 6c 69 6e 6b 20 61 6e 64 | 20 6c 6f 67 69 63 61 6c |link and| logical|
|00005af0| 20 74 68 72 65 61 64 20 | 62 65 74 77 65 65 6e 20 | thread |between |
|00005b00| 74 68 65 20 68 6f 73 74 | 20 61 64 61 70 74 65 72 |the host| adapter|
|00005b10| 20 61 6e 64 20 74 68 65 | 20 74 61 72 67 65 74 20 | and the| target |
|00005b20| 0a 63 6f 6e 74 72 6f 6c | 6c 65 72 2e 20 20 41 6c |.control|ler. Al|
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|00005b60| 68 6f 73 74 20 61 64 61 | 70 74 65 72 20 0a 61 72 |host ada|pter .ar|
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|00005bc0| 63 68 61 6e 6e 65 6c 20 | 63 61 6e 20 73 75 70 70 |channel |can supp|
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|00005be0| 65 70 65 6e 64 65 6e 74 | 20 75 70 6f 6e 20 69 74 |ependent| upon it|
|00005bf0| 73 20 64 65 73 69 67 6e | 2e 20 20 54 68 65 20 53 |s design|. The S|
|00005c00| 43 53 49 20 0a 0a 64 65 | 66 69 6e 69 74 69 6f 6e |CSI ..de|finition|
|00005c10| 20 63 6f 75 6c 64 2c 20 | 69 6e 20 74 68 65 6f 72 | could, |in theor|
|00005c20| 79 2c 20 73 75 70 70 6f | 72 74 20 61 6e 20 49 2f |y, suppo|rt an I/|
|00005c30| 4f 20 63 68 61 6e 6e 65 | 6c 20 77 69 74 68 20 75 |O channe|l with u|
|00005c40| 70 20 74 6f 20 35 36 20 | 73 75 62 63 68 61 6e 6e |p to 56 |subchann|
|00005c50| 65 6c 73 20 0a 28 31 34 | 2c 33 33 36 20 73 75 62 |els .(14|,336 sub|
|00005c60| 63 68 61 6e 6e 65 6c 73 | 2c 20 69 66 20 74 68 65 |channels|, if the|
|00005c70| 20 45 58 54 45 4e 44 45 | 44 20 49 44 45 4e 54 49 | EXTENDE|D IDENTI|
|00005c80| 46 59 20 6d 65 73 73 61 | 67 65 20 69 73 20 69 6d |FY messa|ge is im|
|00005c90| 70 6c 65 6d 65 6e 74 65 | 64 29 2e 0a 0a 0a 0a 0a |plemente|d)......|
|00005ca0| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005cb0| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005cc0| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005cd0| 0a 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |. | |
|00005ce0| 20 02 46 69 67 75 72 65 | 20 43 31 2e 20 53 6e 61 | .Figure| C1. Sna|
|00005cf0| 70 73 68 6f 74 20 50 72 | 69 6f 72 20 74 6f 20 49 |pshot Pr|ior to I|
|00005d00| 6e 69 74 69 61 6c 20 53 | 65 6c 65 63 74 69 6f 6e |nitial S|election|
|00005d10| 02 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005d20| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005d30| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 0a 0a 0a 0a 0a 0a |........|........|
|00005d40| 0a 0a 0a 0a 0a 0a 0a 0a | 0a 0a 20 20 20 20 20 20 |........|.. |
|00005d50| 20 20 20 20 20 20 20 20 | 20 20 20 20 02 46 69 67 | | .Fig|
|00005d60| 75 72 65 20 43 32 2e 20 | 53 6e 61 70 73 68 6f 74 |ure C2. |Snapshot|
|00005d70| 20 50 72 69 6f 72 20 74 | 6f 20 44 61 74 61 20 54 | Prior t|o Data T|
|00005d80| 72 61 6e 73 66 65 72 02 | 0a 0a 1a 1a 1a 1a 1a 1a |ransfer.|........|
|00005d90| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00005da0| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00005db0| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 1a 1a 1a |........|........|
|00005dc0| 1a 1a 1a 1a 1a 1a 1a 1a | 1a 1a 1a 1a 1a 0a 2e 70 |........|.......p|
|00005dd0| 6e 20 31 38 34 0a 2e 66 | 6f 20 41 70 70 65 6e 64 |n 184..f|o Append|
|00005de0| 69 78 20 44 20 20 20 20 | 20 20 20 20 20 20 20 20 |ix D | |
|00005df0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 23 | | #|
|00005e00| 0a 02 41 70 70 65 6e 64 | 69 78 20 44 20 20 02 0a |..Append|ix D ..|
|00005e10| 0a 02 52 65 63 6f 6d 6d | 65 6e 64 65 64 20 53 68 |..Recomm|ended Sh|
|00005e20| 69 65 6c 64 65 64 20 43 | 6f 6e 6e 65 63 74 6f 72 |ielded C|onnector|
|00005e30| 73 02 0a 0a 0a 54 68 72 | 65 65 20 61 6c 74 65 72 |s....Thr|ee alter|
|00005e40| 6e 61 74 69 76 65 20 73 | 68 69 65 6c 64 65 64 20 |native s|hielded |
|00005e50| 63 6f 6e 6e 65 63 74 6f | 72 20 73 79 73 74 65 6d |connecto|r system|
|00005e60| 73 20 61 72 65 20 64 65 | 66 69 6e 65 64 20 62 79 |s are de|fined by|
|00005e70| 20 74 68 69 73 20 61 70 | 70 65 6e 64 69 78 2e 20 | this ap|pendix. |
|00005e80| 20 0a 46 6f 72 20 65 61 | 63 68 20 61 6c 74 65 72 | .For ea|ch alter|
|00005e90| 6e 61 74 69 76 65 2c 20 | 74 68 65 20 63 6f 6e 6e |native, |the conn|
|00005ea0| 65 63 74 6f 72 20 73 68 | 69 65 6c 64 69 6e 67 20 |ector sh|ielding |
|00005eb0| 73 79 73 74 65 6d 20 73 | 68 61 6c 6c 20 70 72 6f |system s|hall pro|
|00005ec0| 76 69 64 65 20 61 20 64 | 63 20 0a 72 65 73 69 73 |vide a d|c .resis|
|00005ed0| 74 61 6e 63 65 20 6f 66 | 20 6c 65 73 73 20 74 68 |tance of| less th|
|00005ee0| 61 6e 20 31 30 0f 6d 69 | 6c 6c 69 6f 68 6d 73 20 |an 10.mi|lliohms |
|00005ef0| 66 72 6f 6d 20 74 68 65 | 20 63 61 62 6c 65 20 73 |from the| cable s|
|00005f00| 68 69 65 6c 64 20 61 74 | 20 69 74 73 20 74 65 72 |hield at| its ter|
|00005f10| 6d 69 6e 61 74 69 6f 6e | 20 0a 70 6f 69 6e 74 20 |mination| .point |
|00005f20| 74 6f 20 74 68 65 20 53 | 43 53 49 20 64 65 76 69 |to the S|CSI devi|
|00005f30| 63 65 20 65 6e 63 6c 6f | 73 75 72 65 2e 0a 0a 20 |ce enclo|sure... |
|00005f40| 20 49 6e 20 6f 72 64 65 | 72 20 74 6f 20 73 75 70 | In orde|r to sup|
|00005f50| 70 6f 72 74 20 64 61 69 | 73 79 2d 63 68 61 69 6e |port dai|sy-chain|
|00005f60| 20 63 6f 6e 6e 65 63 74 | 69 6f 6e 73 2c 20 53 43 | connect|ions, SC|
|00005f70| 53 49 20 64 65 76 69 63 | 65 73 20 74 68 61 74 20 |SI devic|es that |
|00005f80| 75 73 65 20 73 68 69 65 | 6c 64 65 64 20 0a 63 6f |use shie|lded .co|
|00005f90| 6e 6e 65 63 74 6f 72 73 | 20 73 68 6f 75 6c 64 20 |nnectors| should |
|00005fa0| 70 72 6f 76 69 64 65 20 | 74 77 6f 20 73 68 69 65 |provide |two shie|
|00005fb0| 6c 64 65 64 20 64 65 76 | 69 63 65 20 63 6f 6e 6e |lded dev|ice conn|
|00005fc0| 65 63 74 6f 72 73 20 6f | 6e 20 74 68 65 20 64 65 |ectors o|n the de|
|00005fd0| 76 69 63 65 20 0a 65 6e | 63 6c 6f 73 75 72 65 2e |vice .en|closure.|
|00005fe0| 20 20 54 68 65 73 65 20 | 74 77 6f 20 63 6f 6e 6e | These |two conn|
|00005ff0| 65 63 74 6f 72 73 20 6d | 61 79 20 62 65 20 77 69 |ectors m|ay be wi|
|00006000| 72 65 64 20 22 6f 6e 65 | 2d 74 6f 2d 6f 6e 65 22 |red "one|-to-one"|
|00006010| 20 77 69 74 68 20 61 20 | 73 74 75 62 20 74 6f 20 | with a |stub to |
|00006020| 74 68 65 20 0a 53 43 53 | 49 20 64 65 76 69 63 65 |the .SCS|I device|
|00006030| 27 73 20 64 72 69 76 65 | 72 73 20 61 6e 64 20 72 |'s drive|rs and r|
|00006040| 65 63 65 69 76 65 72 73 | 20 70 72 6f 76 69 64 65 |eceivers| provide|
|00006050| 64 20 74 68 65 20 6d 61 | 78 69 6d 75 6d 20 73 74 |d the ma|ximum st|
|00006060| 75 62 20 6c 65 6e 67 74 | 68 20 69 73 20 6e 6f 74 |ub lengt|h is not|
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|00006080| 65 72 6e 61 74 69 76 65 | 6c 79 2c 20 74 77 6f 20 |ernative|ly, two |
|00006090| 63 61 62 6c 65 73 20 6d | 61 79 20 62 65 20 72 75 |cables m|ay be ru|
|000060a0| 6e 20 66 72 6f 6d 20 74 | 68 65 20 74 77 6f 20 73 |n from t|he two s|
|000060b0| 68 69 65 6c 64 65 64 20 | 0a 63 6f 6e 6e 65 63 74 |hielded |.connect|
|000060c0| 6f 72 73 20 74 6f 20 74 | 68 65 20 64 72 69 76 65 |ors to t|he drive|
|000060d0| 72 73 20 61 6e 64 20 72 | 65 63 65 69 76 65 72 73 |rs and r|eceivers|
|000060e0| 20 73 6f 20 74 68 61 74 | 20 74 68 65 20 6d 61 78 | so that| the max|
|000060f0| 69 6d 75 6d 20 73 74 75 | 62 20 6c 65 6e 67 74 68 |imum stu|b length|
|00006100| 20 69 73 20 6e 6f 74 20 | 0a 76 69 6f 6c 61 74 65 | is not |.violate|
|00006110| 64 2e 20 20 54 68 65 20 | 6c 65 6e 67 74 68 20 6f |d. The |length o|
|00006120| 66 20 74 68 65 20 63 61 | 62 6c 65 20 77 69 74 68 |f the ca|ble with|
|00006130| 69 6e 20 74 68 65 20 64 | 65 76 69 63 65 20 65 6e |in the d|evice en|
|00006140| 63 6c 6f 73 75 72 65 20 | 69 73 20 69 6e 63 6c 75 |closure |is inclu|
|00006150| 64 65 64 20 0a 77 68 65 | 6e 20 63 61 6c 63 75 6c |ded .whe|n calcul|
|00006160| 61 74 69 6e 67 20 74 68 | 65 20 74 6f 74 61 6c 20 |ating th|e total |
|00006170| 63 61 62 6c 65 20 6c 65 | 6e 67 74 68 20 6f 66 20 |cable le|ngth of |
|00006180| 74 68 65 20 53 43 53 49 | 20 62 75 73 2e 0a 0a 20 |the SCSI| bus... |
|00006190| 20 02 44 31 20 53 68 69 | 65 6c 64 65 64 20 43 6f | .D1 Shi|elded Co|
|000061a0| 6e 6e 65 63 74 6f 72 2c | 20 41 6c 74 65 72 6e 61 |nnector,| Alterna|
|000061b0| 74 69 76 65 20 31 2e 02 | 20 20 54 68 65 20 73 68 |tive 1..| The sh|
|000061c0| 69 65 6c 64 65 64 20 63 | 61 62 6c 65 20 63 6f 6e |ielded c|able con|
|000061d0| 6e 65 63 74 6f 72 20 0a | 28 46 69 67 75 72 65 20 |nector .|(Figure |
|000061e0| 44 31 29 20 73 68 61 6c | 6c 20 62 65 20 61 20 35 |D1) shal|l be a 5|
|000061f0| 30 2d 63 6f 6e 64 75 63 | 74 6f 72 20 63 6f 6e 6e |0-conduc|tor conn|
|00006200| 65 63 74 6f 72 20 63 6f | 6e 73 69 73 74 69 6e 67 |ector co|nsisting|
|00006210| 20 6f 66 20 74 77 6f 20 | 72 6f 77 73 20 6f 66 20 | of two |rows of |
|00006220| 32 35 20 0a 66 65 6d 61 | 6c 65 20 63 6f 6e 74 61 |25 .fema|le conta|
|00006230| 63 74 73 20 77 69 74 68 | 20 61 64 6a 61 63 65 6e |cts with| adjacen|
|00006240| 74 20 63 6f 6e 74 61 63 | 74 73 20 32 2e 35 34 20 |t contac|ts 2.54 |
|00006250| 6d 6d 20 28 30 2e 31 20 | 69 6e 29 20 61 70 61 72 |mm (0.1 |in) apar|
|00006260| 74 2e 20 20 54 68 65 20 | 6e 6f 6e 6d 61 74 69 6e |t. The |nonmatin|
|00006270| 67 20 0a 70 6f 72 74 69 | 6f 6e 20 6f 66 20 74 68 |g .porti|on of th|
|00006280| 65 20 63 6f 6e 6e 65 63 | 74 6f 72 20 69 73 20 73 |e connec|tor is s|
|00006290| 68 6f 77 6e 20 66 6f 72 | 20 72 65 66 65 72 65 6e |hown for| referen|
|000062a0| 63 65 20 6f 6e 6c 79 2e | 0a 0a 20 20 54 68 65 20 |ce only.|.. The |
|000062b0| 73 68 69 65 6c 64 65 64 | 20 53 43 53 49 20 64 65 |shielded| SCSI de|
|000062c0| 76 69 63 65 20 63 6f 6e | 6e 65 63 74 6f 72 20 28 |vice con|nector (|
|000062d0| 46 69 67 75 72 65 20 44 | 32 29 20 73 68 61 6c 6c |Figure D|2) shall|
|000062e0| 20 62 65 20 61 20 35 30 | 2d 63 6f 6e 64 75 63 74 | be a 50|-conduct|
|000062f0| 6f 72 20 0a 63 6f 6e 6e | 65 63 74 6f 72 20 63 6f |or .conn|ector co|
|00006300| 6e 73 69 73 74 69 6e 67 | 20 6f 66 20 74 77 6f 20 |nsisting| of two |
|00006310| 72 6f 77 73 20 6f 66 20 | 32 35 20 6d 61 6c 65 20 |rows of |25 male |
|00006320| 70 69 6e 73 20 77 69 74 | 68 20 61 64 6a 61 63 65 |pins wit|h adjace|
|00006330| 6e 74 20 70 69 6e 73 20 | 32 2e 35 34 20 6d 6d 20 |nt pins |2.54 mm |
|00006340| 0a 28 30 2e 31 20 69 6e | 29 20 61 70 61 72 74 2e |.(0.1 in|) apart.|
|00006350| 20 20 54 68 65 20 6e 6f | 6e 6d 61 74 69 6e 67 20 | The no|nmating |
|00006360| 70 6f 72 74 69 6f 6e 20 | 6f 66 20 74 68 65 20 63 |portion |of the c|
|00006370| 6f 6e 6e 65 63 74 6f 72 | 20 69 73 20 73 68 6f 77 |onnector| is show|
|00006380| 6e 20 66 6f 72 20 72 65 | 66 65 72 65 6e 63 65 20 |n for re|ference |
|00006390| 0a 6f 6e 6c 79 2e 0a 0a | 20 20 54 68 65 20 63 6f |.only...| The co|
|000063a0| 6e 6e 65 63 74 6f 72 20 | 70 69 6e 20 61 73 73 69 |nnector |pin assi|
|000063b0| 67 6e 6d 65 6e 74 73 20 | 73 68 61 6c 6c 20 62 65 |gnments |shall be|
|000063c0| 20 61 73 20 73 68 6f 77 | 6e 20 69 6e 20 54 61 62 | as show|n in Tab|
|000063d0| 6c 65 20 34 2d 31 20 66 | 6f 72 20 73 69 6e 67 6c |le 4-1 f|or singl|
|000063e0| 65 2d 0a 65 6e 64 65 64 | 20 64 72 69 76 65 72 73 |e-.ended| drivers|
|000063f0| 20 61 6e 64 20 61 73 20 | 73 68 6f 77 6e 20 69 6e | and as |shown in|
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