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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 07:13:05 1990"
| default
| |
| 99%
| file
| data
| default
| |
| 100%
| TrID
| E-Mail message (Var. 2)
| default
| |
| 100%
| perlTextCheck
| Likely Text (Perl)
| default
| |
| 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 37 |DU Thu M|ar 22 07|
|00000030| 3a 31 33 3a 30 35 20 31 | 39 39 30 0a 46 6c 61 67 |:13:05 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 32 36 38 3b 20 | 54 68 75 2c 20 32 32 20 |A28268; |Thu, 22 |
|000000e0| 4d 61 72 20 39 30 20 30 | 37 3a 31 32 3a 32 33 20 |Mar 90 0|7:12:23 |
|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 33 31 37 3b |34)..id |AA14317;|
|00000130| 20 54 68 75 2c 20 32 32 | 20 4d 61 72 20 39 30 20 | Thu, 22| Mar 90 |
|00000140| 30 38 3a 31 32 3a 35 33 | 20 2d 30 35 30 30 0a 4d |08:12:53| -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 33 31 32 2e 41 | 41 31 34 33 31 37 40 52 |221312.A|A14317@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 32 20 | scsiDoc|s-Part2 |
|000001c0| 6f 66 20 37 2e 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 38 3a 31 32 | 22 Mar |90 08:12|
|000001e0| 3a 34 35 20 2d 30 35 30 | 30 0a 46 72 6f 6d 3a 20 |:45 -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 53 65 63 | 74 69 6f 6e 20 35 20 20 |..fo Sec|tion 5 |
|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 02 35 2e 20 | | #..5. |
|00000240| 4c 6f 67 69 63 61 6c 20 | 43 68 61 72 61 63 74 65 |Logical |Characte|
|00000250| 72 69 73 74 69 63 73 02 | 0a 0a 02 35 2e 31 20 53 |ristics.|...5.1 S|
|00000260| 43 53 49 20 42 75 73 20 | 50 68 61 73 65 73 2e 02 |CSI Bus |Phases..|
|00000270| 20 20 54 68 65 20 53 43 | 53 49 20 61 72 63 68 69 | The SC|SI archi|
|00000280| 74 65 63 74 75 72 65 20 | 69 6e 63 6c 75 64 65 73 |tecture |includes|
|00000290| 20 65 69 67 68 74 20 64 | 69 73 74 69 6e 63 74 20 | eight d|istinct |
|000002a0| 70 68 61 73 65 73 3a 0a | 0a 20 20 42 55 53 20 46 |phases:.|. BUS F|
|000002b0| 52 45 45 20 70 68 61 73 | 65 0a 20 20 41 52 42 49 |REE phas|e. ARBI|
|000002c0| 54 52 41 54 49 4f 4e 20 | 70 68 61 73 65 0a 20 20 |TRATION |phase. |
|000002d0| 53 45 4c 45 43 54 49 4f | 4e 20 70 68 61 73 65 0a |SELECTIO|N phase.|
|000002e0| 20 20 52 45 53 45 4c 45 | 43 54 49 4f 4e 20 70 68 | RESELE|CTION ph|
|000002f0| 61 73 65 0a 20 20 43 4f | 4d 4d 41 4e 44 20 70 68 |ase. CO|MMAND ph|
|00000300| 61 73 65 20 20 5c 0a 20 | 20 44 41 54 41 20 70 68 |ase \. | DATA ph|
|00000310| 61 73 65 20 20 20 20 20 | 20 5c 20 20 20 54 68 65 |ase | \ The|
|00000320| 73 65 20 70 68 61 73 65 | 73 20 61 72 65 20 63 6f |se phase|s are co|
|00000330| 6c 6c 65 63 74 69 76 65 | 6c 79 20 74 65 72 6d 65 |llective|ly terme|
|00000340| 64 20 74 68 65 0a 20 20 | 53 54 41 54 55 53 20 70 |d the. |STATUS p|
|00000350| 68 61 73 65 20 20 20 20 | 2f 20 20 20 69 6e 66 6f |hase |/ info|
|00000360| 72 6d 61 74 69 6f 6e 20 | 74 72 61 6e 73 66 65 72 |rmation |transfer|
|00000370| 20 70 68 61 73 65 73 2e | 0a 20 20 4d 45 53 53 41 | phases.|. MESSA|
|00000380| 47 45 20 70 68 61 73 65 | 20 20 2f 0a 0a 20 20 54 |GE phase| /.. T|
|00000390| 68 65 20 53 43 53 49 20 | 62 75 73 20 63 61 6e 20 |he SCSI |bus can |
|000003a0| 6e 65 76 65 72 20 62 65 | 20 69 6e 20 6d 6f 72 65 |never be| in more|
|000003b0| 20 74 68 61 6e 20 6f 6e | 65 20 70 68 61 73 65 20 | than on|e phase |
|000003c0| 61 74 20 61 6e 79 20 67 | 69 76 65 6e 20 74 69 6d |at any g|iven tim|
|000003d0| 65 2e 20 20 55 6e 6c 65 | 73 73 20 0a 6f 74 68 65 |e. Unle|ss .othe|
|000003e0| 72 77 69 73 65 20 6e 6f | 74 65 64 20 69 6e 20 74 |rwise no|ted in t|
|000003f0| 68 65 20 66 6f 6c 6c 6f | 77 69 6e 67 20 64 65 73 |he follo|wing des|
|00000400| 63 72 69 70 74 69 6f 6e | 73 2c 20 73 69 67 6e 61 |cription|s, signa|
|00000410| 6c 73 20 74 68 61 74 20 | 61 72 65 20 6e 6f 74 20 |ls that |are not |
|00000420| 6d 65 6e 74 69 6f 6e 65 | 64 20 0a 73 68 61 6c 6c |mentione|d .shall|
|00000430| 20 6e 6f 74 20 62 65 20 | 61 73 73 65 72 74 65 64 | not be |asserted|
|00000440| 2e 0a 0a 20 20 02 35 2e | 31 2e 31 20 42 55 53 20 |... .5.|1.1 BUS |
|00000450| 46 52 45 45 20 50 68 61 | 73 65 2e 02 20 20 54 68 |FREE Pha|se.. Th|
|00000460| 65 20 42 55 53 20 46 52 | 45 45 20 70 68 61 73 65 |e BUS FR|EE phase|
|00000470| 20 69 73 20 75 73 65 64 | 20 74 6f 20 69 6e 64 69 | is used| to indi|
|00000480| 63 61 74 65 20 74 68 61 | 74 20 6e 6f 20 53 43 53 |cate tha|t no SCS|
|00000490| 49 20 0a 64 65 76 69 63 | 65 20 69 73 20 61 63 74 |I .devic|e is act|
|000004a0| 69 76 65 6c 79 20 75 73 | 69 6e 67 20 74 68 65 20 |ively us|ing the |
|000004b0| 53 43 53 49 20 62 75 73 | 20 61 6e 64 20 74 68 61 |SCSI bus| and tha|
|000004c0| 74 20 69 74 20 69 73 20 | 61 76 61 69 6c 61 62 6c |t it is |availabl|
|000004d0| 65 20 66 6f 72 20 73 75 | 62 73 65 71 75 65 6e 74 |e for su|bsequent|
|000004e0| 20 0a 75 73 65 72 73 2e | 0a 0a 20 20 53 43 53 49 | .users.|.. SCSI|
|000004f0| 20 64 65 76 69 63 65 73 | 20 73 68 61 6c 6c 20 64 | devices| shall d|
|00000500| 65 74 65 63 74 20 74 68 | 65 20 42 55 53 20 46 52 |etect th|e BUS FR|
|00000510| 45 45 20 70 68 61 73 65 | 20 61 66 74 65 72 20 53 |EE phase| after S|
|00000520| 45 4c 20 61 6e 64 20 42 | 53 59 20 61 72 65 20 62 |EL and B|SY are b|
|00000530| 6f 74 68 20 0a 66 61 6c | 73 65 20 66 6f 72 20 61 |oth .fal|se for a|
|00000540| 74 20 6c 65 61 73 74 20 | 61 20 62 75 73 20 73 65 |t least |a bus se|
|00000550| 74 74 6c 65 20 64 65 6c | 61 79 2e 0a 0a 20 20 53 |ttle del|ay... S|
|00000560| 43 53 49 20 64 65 76 69 | 63 65 73 20 73 68 61 6c |CSI devi|ces shal|
|00000570| 6c 20 72 65 6c 65 61 73 | 65 20 61 6c 6c 20 53 43 |l releas|e all SC|
|00000580| 53 49 20 62 75 73 20 73 | 69 67 6e 61 6c 73 20 77 |SI bus s|ignals w|
|00000590| 69 74 68 69 6e 20 61 20 | 62 75 73 20 63 6c 65 61 |ithin a |bus clea|
|000005a0| 72 20 64 65 6c 61 79 20 | 0a 61 66 74 65 72 20 42 |r delay |.after B|
|000005b0| 53 59 20 61 6e 64 20 53 | 45 4c 20 62 65 63 6f 6d |SY and S|EL becom|
|000005c0| 65 20 63 6f 6e 74 69 6e | 75 6f 75 73 6c 79 20 66 |e contin|uously f|
|000005d0| 61 6c 73 65 20 66 6f 72 | 20 61 20 62 75 73 20 73 |alse for| a bus s|
|000005e0| 65 74 74 6c 65 20 64 65 | 6c 61 79 2e 20 20 49 66 |ettle de|lay. If|
|000005f0| 20 61 6e 20 0a 53 43 53 | 49 20 64 65 76 69 63 65 | an .SCS|I device|
|00000600| 20 72 65 71 75 69 72 65 | 73 20 6d 6f 72 65 20 74 | require|s more t|
|00000610| 68 61 6e 20 61 20 62 75 | 73 20 73 65 74 74 6c 65 |han a bu|s settle|
|00000620| 20 64 65 6c 61 79 20 74 | 6f 20 64 65 74 65 63 74 | delay t|o detect|
|00000630| 20 74 68 65 20 42 55 53 | 20 46 52 45 45 20 70 68 | the BUS| FREE ph|
|00000640| 61 73 65 20 0a 74 68 65 | 6e 20 69 74 20 73 68 61 |ase .the|n it sha|
|00000650| 6c 6c 20 72 65 6c 65 61 | 73 65 20 61 6c 6c 20 53 |ll relea|se all S|
|00000660| 43 53 49 20 62 75 73 20 | 73 69 67 6e 61 6c 73 20 |CSI bus |signals |
|00000670| 77 69 74 68 69 6e 20 61 | 20 62 75 73 20 63 6c 65 |within a| bus cle|
|00000680| 61 72 20 64 65 6c 61 79 | 20 6d 69 6e 75 73 20 74 |ar delay| minus t|
|00000690| 68 65 20 0a 65 78 63 65 | 73 73 20 74 69 6d 65 20 |he .exce|ss time |
|000006a0| 74 6f 20 64 65 74 65 63 | 74 20 74 68 65 20 42 55 |to detec|t the BU|
|000006b0| 53 20 46 52 45 45 20 70 | 68 61 73 65 2e 20 20 54 |S FREE p|hase. T|
|000006c0| 68 65 20 74 6f 74 61 6c | 20 74 69 6d 65 20 74 6f |he total| time to|
|000006d0| 20 63 6c 65 61 72 20 74 | 68 65 20 53 43 53 49 20 | clear t|he SCSI |
|000006e0| 0a 62 75 73 20 73 68 61 | 6c 6c 20 6e 6f 74 20 65 |.bus sha|ll not e|
|000006f0| 78 63 65 65 64 20 61 20 | 62 75 73 20 73 65 74 74 |xceed a |bus sett|
|00000700| 6c 65 20 64 65 6c 61 79 | 20 70 6c 75 73 20 61 20 |le delay| plus a |
|00000710| 62 75 73 20 63 6c 65 61 | 72 20 64 65 6c 61 79 2e |bus clea|r delay.|
|00000720| 0a 0a 20 20 02 35 2e 31 | 2e 32 20 41 52 42 49 54 |.. .5.1|.2 ARBIT|
|00000730| 52 41 54 49 4f 4e 20 50 | 68 61 73 65 2e 02 20 20 |RATION P|hase.. |
|00000740| 54 68 65 20 41 52 42 49 | 54 52 41 54 49 4f 4e 20 |The ARBI|TRATION |
|00000750| 70 68 61 73 65 20 61 6c | 6c 6f 77 73 20 6f 6e 65 |phase al|lows one|
|00000760| 20 53 43 53 49 20 64 65 | 76 69 63 65 20 74 6f 20 | SCSI de|vice to |
|00000770| 0a 67 61 69 6e 20 63 6f | 6e 74 72 6f 6c 20 6f 66 |.gain co|ntrol of|
|00000780| 20 74 68 65 20 53 43 53 | 49 20 62 75 73 20 73 6f | the SCS|I bus so|
|00000790| 20 74 68 61 74 20 69 74 | 20 63 61 6e 20 61 73 73 | that it| can ass|
|000007a0| 75 6d 65 20 74 68 65 20 | 72 6f 6c 65 20 6f 66 20 |ume the |role of |
|000007b0| 61 6e 20 69 6e 69 74 69 | 61 74 6f 72 20 6f 72 20 |an initi|ator or |
|000007c0| 0a 74 61 72 67 65 74 2e | 0a 0a 4e 4f 54 45 3a 20 |.target.|..NOTE: |
|000007d0| 20 49 6d 70 6c 65 6d 65 | 6e 74 61 74 69 6f 6e 20 | Impleme|ntation |
|000007e0| 6f 66 20 74 68 65 20 41 | 52 42 49 54 52 41 54 49 |of the A|RBITRATI|
|000007f0| 4f 4e 20 70 68 61 73 65 | 20 69 73 20 61 20 73 79 |ON phase| is a sy|
|00000800| 73 74 65 6d 20 6f 70 74 | 69 6f 6e 2e 20 20 53 79 |stem opt|ion. Sy|
|00000810| 73 74 65 6d 73 20 0a 74 | 68 61 74 20 64 6f 20 6e |stems .t|hat do n|
|00000820| 6f 74 20 69 6d 70 6c 65 | 6d 65 6e 74 20 74 68 69 |ot imple|ment thi|
|00000830| 73 20 6f 70 74 69 6f 6e | 20 63 61 6e 20 68 61 76 |s option| can hav|
|00000840| 65 20 6f 6e 6c 79 20 6f | 6e 65 20 69 6e 69 74 69 |e only o|ne initi|
|00000850| 61 74 6f 72 2e 20 20 54 | 68 65 20 0a 41 52 42 49 |ator. T|he .ARBI|
|00000860| 54 52 41 54 49 4f 4e 20 | 70 68 61 73 65 20 69 73 |TRATION |phase is|
|00000870| 20 72 65 71 75 69 72 65 | 64 20 66 6f 72 20 73 79 | require|d for sy|
|00000880| 73 74 65 6d 73 20 74 68 | 61 74 20 75 73 65 20 74 |stems th|at use t|
|00000890| 68 65 20 52 45 53 45 4c | 45 43 54 49 4f 4e 20 70 |he RESEL|ECTION p|
|000008a0| 68 61 73 65 2e 0a 0a 20 | 20 54 68 65 20 70 72 6f |hase... | The pro|
|000008b0| 63 65 64 75 72 65 20 66 | 6f 72 20 61 6e 20 53 43 |cedure f|or an SC|
|000008c0| 53 49 20 64 65 76 69 63 | 65 20 74 6f 20 6f 62 74 |SI devic|e to obt|
|000008d0| 61 69 6e 20 63 6f 6e 74 | 72 6f 6c 20 6f 66 20 74 |ain cont|rol of t|
|000008e0| 68 65 20 53 43 53 49 20 | 62 75 73 20 69 73 20 61 |he SCSI |bus is a|
|000008f0| 73 20 0a 66 6f 6c 6c 6f | 77 73 3a 0a 0a 20 20 28 |s .follo|ws:.. (|
|00000900| 31 29 20 20 54 68 65 20 | 53 43 53 49 20 64 65 76 |1) The |SCSI dev|
|00000910| 69 63 65 20 73 68 61 6c | 6c 20 66 69 72 73 74 20 |ice shal|l first |
|00000920| 77 61 69 74 20 66 6f 72 | 20 74 68 65 20 42 55 53 |wait for| the BUS|
|00000930| 20 46 52 45 45 20 70 68 | 61 73 65 20 74 6f 20 6f | FREE ph|ase to o|
|00000940| 63 63 75 72 2e 20 20 54 | 68 65 20 0a 42 55 53 20 |ccur. T|he .BUS |
|00000950| 46 52 45 45 20 70 68 61 | 73 65 20 69 73 20 64 65 |FREE pha|se is de|
|00000960| 74 65 63 74 65 64 20 77 | 68 65 6e 65 76 65 72 20 |tected w|henever |
|00000970| 62 6f 74 68 20 42 53 59 | 20 61 6e 64 20 53 45 4c |both BSY| and SEL|
|00000980| 20 61 72 65 20 73 69 6d | 75 6c 74 61 6e 65 6f 75 | are sim|ultaneou|
|00000990| 73 6c 79 20 61 6e 64 20 | 0a 63 6f 6e 74 69 6e 75 |sly and |.continu|
|000009a0| 6f 75 73 6c 79 20 66 61 | 6c 73 65 20 66 6f 72 20 |ously fa|lse for |
|000009b0| 61 20 6d 69 6e 69 6d 75 | 6d 20 6f 66 20 61 20 62 |a minimu|m of a b|
|000009c0| 75 73 20 73 65 74 74 6c | 65 20 64 65 6c 61 79 2e |us settl|e delay.|
|000009d0| 20 20 28 49 6d 70 6c 65 | 6d 65 6e 74 6f 72 73 20 | (Imple|mentors |
|000009e0| 4e 6f 74 65 3a 20 20 0a | 54 68 69 73 20 62 75 73 |Note: .|This bus|
|000009f0| 20 73 65 74 74 6c 65 20 | 64 65 6c 61 79 20 69 73 | settle |delay is|
|00000a00| 20 6e 65 63 65 73 73 61 | 72 79 20 62 65 63 61 75 | necessa|ry becau|
|00000a10| 73 65 20 61 20 74 72 61 | 6e 73 6d 69 73 73 69 6f |se a tra|nsmissio|
|00000a20| 6e 20 6c 69 6e 65 20 70 | 68 65 6e 6f 6d 65 6e 6f |n line p|henomeno|
|00000a30| 6e 20 0a 6b 6e 6f 77 6e | 20 61 73 20 61 20 22 77 |n .known| as a "w|
|00000a40| 69 72 65 2d 4f 52 20 67 | 6c 69 74 63 68 22 20 6d |ire-OR g|litch" m|
|00000a50| 61 79 20 63 61 75 73 65 | 20 42 53 59 20 74 6f 20 |ay cause| BSY to |
|00000a60| 62 72 69 65 66 6c 79 20 | 61 70 70 65 61 72 20 66 |briefly |appear f|
|00000a70| 61 6c 73 65 2c 20 65 76 | 65 6e 20 74 68 6f 75 67 |alse, ev|en thoug|
|00000a80| 68 20 0a 69 74 20 69 73 | 20 62 65 69 6e 67 20 64 |h .it is| being d|
|00000a90| 72 69 76 65 6e 20 74 72 | 75 65 2e 29 0a 0a 20 20 |riven tr|ue.).. |
|00000aa0| 28 32 29 20 20 54 68 65 | 20 53 43 53 49 20 64 65 |(2) The| SCSI de|
|00000ab0| 76 69 63 65 20 73 68 61 | 6c 6c 20 77 61 69 74 20 |vice sha|ll wait |
|00000ac0| 61 20 6d 69 6e 69 6d 75 | 6d 20 6f 66 20 61 20 62 |a minimu|m of a b|
|00000ad0| 75 73 20 66 72 65 65 20 | 64 65 6c 61 79 20 61 66 |us free |delay af|
|00000ae0| 74 65 72 20 0a 64 65 74 | 65 63 74 69 6f 6e 20 6f |ter .det|ection o|
|00000af0| 66 20 74 68 65 20 42 55 | 53 20 46 52 45 45 20 70 |f the BU|S FREE p|
|00000b00| 68 61 73 65 20 28 69 2e | 65 2e 20 61 66 74 65 72 |hase (i.|e. after|
|00000b10| 20 42 53 59 20 61 6e 64 | 20 53 45 4c 20 61 72 65 | BSY and| SEL are|
|00000b20| 20 62 6f 74 68 20 66 61 | 6c 73 65 20 66 6f 72 20 | both fa|lse for |
|00000b30| 61 20 0a 62 75 73 20 73 | 65 74 74 6c 65 20 64 65 |a .bus s|ettle de|
|00000b40| 6c 61 79 29 20 62 65 66 | 6f 72 65 20 64 72 69 76 |lay) bef|ore driv|
|00000b50| 69 6e 67 20 61 6e 79 20 | 73 69 67 6e 61 6c 2e 0a |ing any |signal..|
|00000b60| 0a 20 20 28 33 29 20 20 | 46 6f 6c 6c 6f 77 69 6e |. (3) |Followin|
|00000b70| 67 20 74 68 65 20 62 75 | 73 20 66 72 65 65 20 64 |g the bu|s free d|
|00000b80| 65 6c 61 79 20 69 6e 20 | 53 74 65 70 20 28 32 29 |elay in |Step (2)|
|00000b90| 2c 20 74 68 65 20 53 43 | 53 49 20 64 65 76 69 63 |, the SC|SI devic|
|00000ba0| 65 20 6d 61 79 20 61 72 | 62 69 74 72 61 74 65 20 |e may ar|bitrate |
|00000bb0| 0a 66 6f 72 20 74 68 65 | 20 53 43 53 49 20 62 75 |.for the| SCSI bu|
|00000bc0| 73 20 62 79 20 61 73 73 | 65 72 74 69 6e 67 20 62 |s by ass|erting b|
|00000bd0| 6f 74 68 20 42 53 59 20 | 61 6e 64 20 69 74 73 20 |oth BSY |and its |
|00000be0| 6f 77 6e 20 53 43 53 49 | 20 49 44 2c 20 68 6f 77 |own SCSI| ID, how|
|00000bf0| 65 76 65 72 20 74 68 65 | 20 53 43 53 49 20 0a 64 |ever the| SCSI .d|
|00000c00| 65 76 69 63 65 20 73 68 | 61 6c 6c 20 6e 6f 74 20 |evice sh|all not |
|00000c10| 61 72 62 69 74 72 61 74 | 65 20 28 69 2e 65 2e 20 |arbitrat|e (i.e. |
|00000c20| 61 73 73 65 72 74 20 42 | 53 59 20 61 6e 64 20 69 |assert B|SY and i|
|00000c30| 74 73 20 53 43 53 49 20 | 49 44 29 20 69 66 20 6d |ts SCSI |ID) if m|
|00000c40| 6f 72 65 20 74 68 61 6e | 20 61 20 0a 0a 62 75 73 |ore than| a ..bus|
|00000c50| 20 73 65 74 20 64 65 6c | 61 79 20 68 61 73 20 70 | set del|ay has p|
|00000c60| 61 73 73 65 64 20 73 69 | 6e 63 65 20 74 68 65 20 |assed si|nce the |
|00000c70| 42 55 53 20 46 52 45 45 | 20 70 68 61 73 65 20 77 |BUS FREE| phase w|
|00000c80| 61 73 20 6c 61 73 74 20 | 6f 62 73 65 72 76 65 64 |as last |observed|
|00000c90| 2e 20 20 0a 28 49 6d 70 | 6c 65 6d 65 6e 74 6f 72 |. .(Imp|lementor|
|00000ca0| 73 20 4e 6f 74 65 3a 20 | 20 54 68 65 72 65 20 69 |s Note: | There i|
|00000cb0| 73 20 6e 6f 20 6d 61 78 | 69 6d 75 6d 20 64 65 6c |s no max|imum del|
|00000cc0| 61 79 20 62 65 66 6f 72 | 65 20 61 73 73 65 72 74 |ay befor|e assert|
|00000cd0| 69 6e 67 20 42 53 59 20 | 61 6e 64 20 74 68 65 20 |ing BSY |and the |
|00000ce0| 0a 53 43 53 49 20 49 44 | 20 66 6f 6c 6c 6f 77 69 |.SCSI ID| followi|
|00000cf0| 6e 67 20 74 68 65 20 62 | 75 73 20 66 72 65 65 20 |ng the b|us free |
|00000d00| 64 65 6c 61 79 20 69 6e | 20 53 74 65 70 20 28 32 |delay in| Step (2|
|00000d10| 29 20 61 73 20 6c 6f 6e | 67 20 61 73 20 74 68 65 |) as lon|g as the|
|00000d20| 20 62 75 73 20 72 65 6d | 61 69 6e 73 20 69 6e 20 | bus rem|ains in |
|00000d30| 0a 74 68 65 20 42 55 53 | 20 46 52 45 45 20 70 68 |.the BUS| FREE ph|
|00000d40| 61 73 65 2e 20 20 48 6f | 77 65 76 65 72 2c 20 53 |ase. Ho|wever, S|
|00000d50| 43 53 49 20 64 65 76 69 | 63 65 73 20 74 68 61 74 |CSI devi|ces that|
|00000d60| 20 64 65 6c 61 79 20 6c | 6f 6e 67 65 72 20 74 68 | delay l|onger th|
|00000d70| 61 6e 20 61 20 62 75 73 | 20 73 65 74 74 6c 65 20 |an a bus| settle |
|00000d80| 0a 64 65 6c 61 79 20 70 | 6c 75 73 20 61 20 62 75 |.delay p|lus a bu|
|00000d90| 73 20 73 65 74 20 64 65 | 6c 61 79 20 66 72 6f 6d |s set de|lay from|
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|00001d10| 20 69 6e 69 74 69 61 74 | 6f 72 20 65 6e 76 69 72 | initiat|or envir|
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|00002930| 20 20 54 68 65 20 74 61 | 72 67 65 74 20 73 68 61 | The ta|rget sha|
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|00002950| 72 74 69 6e 67 20 42 53 | 59 20 75 6e 74 69 6c 20 |rting BS|Y until |
|00002960| 74 68 65 20 74 61 72 67 | 65 74 20 69 73 20 0a 72 |the targ|et is .r|
|00002970| 65 61 64 79 20 74 6f 20 | 72 65 6c 69 6e 71 75 69 |eady to |relinqui|
|00002980| 73 68 20 74 68 65 20 53 | 43 53 49 20 62 75 73 2e |sh the S|CSI bus.|
|00002990| 0a 0a 4e 4f 54 45 3a 20 | 20 57 68 65 6e 20 74 68 |..NOTE: | When th|
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|00003280| 49 2f 4f 2c 20 61 6e 64 | 20 42 53 59 2e 0a 0a 0a |I/O, and| BSY....|
|00003290| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000032a0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000032b0| 20 20 02 54 61 62 6c 65 | 20 35 2d 31 02 0a 20 20 | .Table| 5-1.. |
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|000032f0| 73 65 73 02 0a 0a 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |ses...==|========|
|00003300| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003310| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003320| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003330| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003340| 3d 3d 3d 3d 0a 20 20 20 | 53 69 67 6e 61 6c 0a 2d |====. |Signal.-|
|00003350| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 0a 0a 4d 53 47 20 |--------|--..MSG |
|00003360| 43 2f 44 20 49 2f 4f 20 | 20 20 50 68 61 73 65 20 |C/D I/O | Phase |
|00003370| 4e 61 6d 65 20 20 20 20 | 20 20 20 20 20 20 44 69 |Name | Di|
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|000033a0| 65 6e 74 0a 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |ent.----|--------|
|000033b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
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|000035a0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000035b0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000035c0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000035d0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000035e0| 3d 3d 3d 3d 3d 3d 3d 3d | 0a 0a 4b 65 79 3a 20 20 |========|..Key: |
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|000037a0| 68 65 20 52 45 51 2f 41 | 43 4b 20 0a 68 61 6e 64 |he REQ/A|CK .hand|
|000037b0| 73 68 61 6b 65 28 73 29 | 20 77 69 74 68 20 43 2f |shake(s)| with C/|
|000037c0| 44 2c 20 49 2f 4f 2c 20 | 61 6e 64 20 4d 53 47 20 |D, I/O, |and MSG |
|000037d0| 69 6e 20 73 75 63 68 20 | 61 20 6d 61 6e 6e 65 72 |in such |a manner|
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|00003800| 20 76 61 6c 69 64 20 66 | 6f 72 20 61 20 62 75 73 | valid f|or a bus|
|00003810| 20 73 65 74 74 6c 65 20 | 64 65 6c 61 79 20 62 65 | settle |delay be|
|00003820| 66 6f 72 65 20 74 68 65 | 20 61 73 73 65 72 74 69 |fore the| asserti|
|00003830| 6f 6e 20 6f 66 20 52 45 | 51 20 6f 66 20 74 68 65 |on of RE|Q of the|
|00003840| 20 0a 66 69 72 73 74 20 | 68 61 6e 64 73 68 61 6b | .first |handshak|
|00003850| 65 20 61 6e 64 20 72 65 | 6d 61 69 6e 20 76 61 6c |e and re|main val|
|00003860| 69 64 20 75 6e 74 69 6c | 20 74 68 65 20 6e 65 67 |id until| the neg|
|00003870| 61 74 69 6f 6e 20 6f 66 | 20 41 43 4b 20 61 74 20 |ation of| ACK at |
|00003880| 74 68 65 20 65 6e 64 20 | 6f 66 20 74 68 65 20 0a |the end |of the .|
|00003890| 6c 61 73 74 20 68 61 6e | 64 73 68 61 6b 65 2e 0a |last han|dshake..|
|000038a0| 0a 20 20 20 20 20 02 35 | 2e 31 2e 35 2e 31 20 41 |. .5|.1.5.1 A|
|000038b0| 73 79 6e 63 68 72 6f 6e | 6f 75 73 20 49 6e 66 6f |synchron|ous Info|
|000038c0| 72 6d 61 74 69 6f 6e 20 | 54 72 61 6e 73 66 65 72 |rmation |Transfer|
|000038d0| 2e 02 20 20 54 68 65 20 | 74 61 72 67 65 74 20 73 |.. The |target s|
|000038e0| 68 61 6c 6c 20 63 6f 6e | 74 72 6f 6c 20 74 68 65 |hall con|trol the|
|000038f0| 20 0a 64 69 72 65 63 74 | 69 6f 6e 20 6f 66 20 69 | .direct|ion of i|
|00003900| 6e 66 6f 72 6d 61 74 69 | 6f 6e 20 74 72 61 6e 73 |nformati|on trans|
|00003910| 66 65 72 20 62 79 20 6d | 65 61 6e 73 20 6f 66 20 |fer by m|eans of |
|00003920| 74 68 65 20 49 2f 4f 20 | 73 69 67 6e 61 6c 2e 20 |the I/O |signal. |
|00003930| 20 57 68 65 6e 20 49 2f | 4f 20 69 73 20 0a 74 72 | When I/|O is .tr|
|00003940| 75 65 2c 20 69 6e 66 6f | 72 6d 61 74 69 6f 6e 20 |ue, info|rmation |
|00003950| 73 68 61 6c 6c 20 62 65 | 20 74 72 61 6e 73 66 65 |shall be| transfe|
|00003960| 72 72 65 64 20 66 72 6f | 6d 20 74 68 65 20 74 61 |rred fro|m the ta|
|00003970| 72 67 65 74 20 74 6f 20 | 74 68 65 20 69 6e 69 74 |rget to |the init|
|00003980| 69 61 74 6f 72 2e 20 20 | 57 68 65 6e 20 0a 49 2f |iator. |When .I/|
|00003990| 4f 20 69 73 20 66 61 6c | 73 65 2c 20 69 6e 66 6f |O is fal|se, info|
|000039a0| 72 6d 61 74 69 6f 6e 20 | 73 68 61 6c 6c 20 62 65 |rmation |shall be|
|000039b0| 20 74 72 61 6e 73 66 65 | 72 72 65 64 20 66 72 6f | transfe|rred fro|
|000039c0| 6d 20 74 68 65 20 69 6e | 69 74 69 61 74 6f 72 20 |m the in|itiator |
|000039d0| 74 6f 20 74 68 65 20 0a | 74 61 72 67 65 74 2e 0a |to the .|target..|
|000039e0| 0a 20 20 49 66 20 49 2f | 4f 20 69 73 20 74 72 75 |. If I/|O is tru|
|000039f0| 65 20 28 74 72 61 6e 73 | 66 65 72 20 74 6f 20 74 |e (trans|fer to t|
|00003a00| 68 65 20 69 6e 69 74 69 | 61 74 6f 72 29 2c 20 74 |he initi|ator), t|
|00003a10| 68 65 20 74 61 72 67 65 | 74 20 73 68 61 6c 6c 20 |he targe|t shall |
|00003a20| 66 69 72 73 74 20 64 72 | 69 76 65 20 0a 44 42 28 |first dr|ive .DB(|
|00003a30| 37 2d 30 2c 50 29 20 74 | 6f 20 74 68 65 69 72 20 |7-0,P) t|o their |
|00003a40| 64 65 73 69 72 65 64 20 | 76 61 6c 75 65 73 2c 20 |desired |values, |
|00003a50| 64 65 6c 61 79 20 61 74 | 20 6c 65 61 73 74 20 6f |delay at| least o|
|00003a60| 6e 65 20 64 65 73 6b 65 | 77 20 64 65 6c 61 79 20 |ne deske|w delay |
|00003a70| 70 6c 75 73 20 61 20 0a | 63 61 62 6c 65 20 73 6b |plus a .|cable sk|
|00003a80| 65 77 20 64 65 6c 61 79 | 2c 20 74 68 65 6e 20 61 |ew delay|, then a|
|00003a90| 73 73 65 72 74 20 52 45 | 51 2e 20 20 44 42 28 37 |ssert RE|Q. DB(7|
|00003aa0| 2d 30 2c 50 29 20 73 68 | 61 6c 6c 20 72 65 6d 61 |-0,P) sh|all rema|
|00003ab0| 69 6e 20 76 61 6c 69 64 | 20 75 6e 74 69 6c 20 41 |in valid| until A|
|00003ac0| 43 4b 20 69 73 20 0a 74 | 72 75 65 20 61 74 20 74 |CK is .t|rue at t|
|00003ad0| 68 65 20 74 61 72 67 65 | 74 2e 20 20 54 68 65 20 |he targe|t. The |
|00003ae0| 69 6e 69 74 69 61 74 6f | 72 20 73 68 61 6c 6c 20 |initiato|r shall |
|00003af0| 72 65 61 64 20 44 42 28 | 37 2d 30 2c 50 29 20 61 |read DB(|7-0,P) a|
|00003b00| 66 74 65 72 20 52 45 51 | 20 69 73 20 74 72 75 65 |fter REQ| is true|
|00003b10| 2c 20 0a 74 68 65 6e 20 | 73 69 67 6e 61 6c 20 69 |, .then |signal i|
|00003b20| 74 73 20 61 63 63 65 70 | 74 61 6e 63 65 20 6f 66 |ts accep|tance of|
|00003b30| 20 74 68 65 20 64 61 74 | 61 20 62 79 20 61 73 73 | the dat|a by ass|
|00003b40| 65 72 74 69 6e 67 20 41 | 43 4b 2e 20 20 57 68 65 |erting A|CK. Whe|
|00003b50| 6e 20 41 43 4b 20 62 65 | 63 6f 6d 65 73 20 0a 74 |n ACK be|comes .t|
|00003b60| 72 75 65 20 61 74 20 74 | 68 65 20 74 61 72 67 65 |rue at t|he targe|
|00003b70| 74 2c 20 74 68 65 20 74 | 61 72 67 65 74 20 6d 61 |t, the t|arget ma|
|00003b80| 79 20 63 68 61 6e 67 65 | 20 6f 72 20 72 65 6c 65 |y change| or rele|
|00003b90| 61 73 65 20 44 42 28 37 | 2d 30 2c 50 29 20 61 6e |ase DB(7|-0,P) an|
|00003ba0| 64 20 73 68 61 6c 6c 20 | 0a 6e 65 67 61 74 65 20 |d shall |.negate |
|00003bb0| 52 45 51 2e 20 20 41 66 | 74 65 72 20 52 45 51 20 |REQ. Af|ter REQ |
|00003bc0| 69 73 20 66 61 6c 73 65 | 20 74 68 65 20 69 6e 69 |is false| the ini|
|00003bd0| 74 69 61 74 6f 72 20 73 | 68 61 6c 6c 20 74 68 65 |tiator s|hall the|
|00003be0| 6e 20 6e 65 67 61 74 65 | 20 41 43 4b 2e 20 20 41 |n negate| ACK. A|
|00003bf0| 66 74 65 72 20 0a 41 43 | 4b 20 69 73 20 66 61 6c |fter .AC|K is fal|
|00003c00| 73 65 20 74 68 65 20 74 | 61 72 67 65 74 20 6d 61 |se the t|arget ma|
|00003c10| 79 20 63 6f 6e 74 69 6e | 75 65 20 74 68 65 20 74 |y contin|ue the t|
|00003c20| 72 61 6e 73 66 65 72 20 | 62 79 20 64 72 69 76 69 |ransfer |by drivi|
|00003c30| 6e 67 20 44 42 28 37 2d | 30 2c 50 29 20 61 6e 64 |ng DB(7-|0,P) and|
|00003c40| 20 0a 61 73 73 65 72 74 | 69 6e 67 20 52 45 51 2c | .assert|ing REQ,|
|00003c50| 20 61 73 20 64 65 73 63 | 72 69 62 65 64 20 61 62 | as desc|ribed ab|
|00003c60| 6f 76 65 2e 0a 0a 20 20 | 49 66 20 49 2f 4f 20 69 |ove... |If I/O i|
|00003c70| 73 20 66 61 6c 73 65 20 | 28 74 72 61 6e 73 66 65 |s false |(transfe|
|00003c80| 72 20 74 6f 20 74 68 65 | 20 74 61 72 67 65 74 29 |r to the| target)|
|00003c90| 20 74 68 65 20 74 61 72 | 67 65 74 20 73 68 61 6c | the tar|get shal|
|00003ca0| 6c 20 72 65 71 75 65 73 | 74 20 0a 69 6e 66 6f 72 |l reques|t .infor|
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|00003cc0| 69 6e 67 20 52 45 51 2e | 20 20 54 68 65 20 69 6e |ing REQ.| The in|
|00003cd0| 69 74 69 61 74 6f 72 20 | 73 68 61 6c 6c 20 64 72 |itiator |shall dr|
|00003ce0| 69 76 65 20 44 42 28 37 | 2d 30 2c 50 29 20 74 6f |ive DB(7|-0,P) to|
|00003cf0| 20 74 68 65 69 72 20 0a | 64 65 73 69 72 65 64 20 | their .|desired |
|00003d00| 76 61 6c 75 65 73 2c 20 | 64 65 6c 61 79 20 61 74 |values, |delay at|
|00003d10| 20 6c 65 61 73 74 20 6f | 6e 65 20 64 65 73 6b 65 | least o|ne deske|
|00003d20| 77 20 64 65 6c 61 79 20 | 70 6c 75 73 20 61 20 63 |w delay |plus a c|
|00003d30| 61 62 6c 65 20 73 6b 65 | 77 20 64 65 6c 61 79 20 |able ske|w delay |
|00003d40| 61 6e 64 20 0a 61 73 73 | 65 72 74 20 41 43 4b 2e |and .ass|ert ACK.|
|00003d50| 20 20 54 68 65 20 69 6e | 69 74 69 61 74 6f 72 20 | The in|itiator |
|00003d60| 73 68 61 6c 6c 20 63 6f | 6e 74 69 6e 75 65 20 74 |shall co|ntinue t|
|00003d70| 6f 20 64 72 69 76 65 20 | 44 42 28 37 2d 30 2c 50 |o drive |DB(7-0,P|
|00003d80| 29 20 75 6e 74 69 6c 20 | 52 45 51 20 69 73 20 0a |) until |REQ is .|
|00003d90| 66 61 6c 73 65 2e 20 20 | 57 68 65 6e 20 41 43 4b |false. |When ACK|
|00003da0| 20 62 65 63 6f 6d 65 73 | 20 74 72 75 65 20 61 74 | becomes| true at|
|00003db0| 20 74 68 65 20 74 61 72 | 67 65 74 2c 20 74 68 65 | the tar|get, the|
|00003dc0| 20 74 61 72 67 65 74 20 | 73 68 61 6c 6c 20 72 65 | target |shall re|
|00003dd0| 61 64 20 44 42 28 37 2d | 30 2c 50 29 2c 20 0a 74 |ad DB(7-|0,P), .t|
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|00003df0| 20 57 68 65 6e 20 52 45 | 51 20 62 65 63 6f 6d 65 | When RE|Q become|
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|00003e10| 6e 69 74 69 61 74 6f 72 | 2c 20 74 68 65 20 69 6e |nitiator|, the in|
|00003e20| 69 74 69 61 74 6f 72 20 | 6d 61 79 20 0a 63 68 61 |itiator |may .cha|
|00003e30| 6e 67 65 20 6f 72 20 72 | 65 6c 65 61 73 65 20 44 |nge or r|elease D|
|00003e40| 42 28 37 2d 30 2c 50 29 | 20 61 6e 64 20 73 68 61 |B(7-0,P)| and sha|
|00003e50| 6c 6c 20 6e 65 67 61 74 | 65 20 41 43 4b 2e 20 20 |ll negat|e ACK. |
|00003e60| 54 68 65 20 74 61 72 67 | 65 74 20 6d 61 79 20 63 |The targ|et may c|
|00003e70| 6f 6e 74 69 6e 75 65 20 | 74 68 65 20 0a 74 72 61 |ontinue |the .tra|
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|00003ea0| 69 62 65 64 20 61 62 6f | 76 65 2e 0a 0a 20 20 20 |ibed abo|ve... |
|00003eb0| 20 20 02 35 2e 31 2e 35 | 2e 32 20 53 79 6e 63 68 | .5.1.5|.2 Synch|
|00003ec0| 72 6f 6e 6f 75 73 20 44 | 61 74 61 20 54 72 61 6e |ronous D|ata Tran|
|00003ed0| 73 66 65 72 20 28 4f 70 | 74 69 6f 6e 61 6c 29 2e |sfer (Op|tional).|
|00003ee0| 02 20 20 53 79 6e 63 68 | 72 6f 6e 6f 75 73 20 64 |. Synch|ronous d|
|00003ef0| 61 74 61 20 74 72 61 6e | 73 66 65 72 20 0a 69 73 |ata tran|sfer .is|
|00003f00| 20 6f 70 74 69 6f 6e 61 | 6c 2c 20 61 6e 64 20 6d | optiona|l, and m|
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|00003f20| 69 6e 20 74 68 65 20 64 | 61 74 61 20 70 68 61 73 |in the d|ata phas|
|00003f30| 65 20 69 66 20 70 72 65 | 76 69 6f 75 73 6c 79 20 |e if pre|viously |
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|00003f60| 74 61 72 67 65 74 20 74 | 68 72 6f 75 67 68 20 74 |target t|hrough t|
|00003f70| 68 65 20 6d 65 73 73 61 | 67 65 20 73 79 73 74 65 |he messa|ge syste|
|00003f80| 6d 20 28 73 65 65 20 53 | 59 4e 43 48 52 4f 4e 4f |m (see S|YNCHRONO|
|00003f90| 55 53 20 44 41 54 41 20 | 0a 54 52 41 4e 53 46 45 |US DATA |.TRANSFE|
|00003fa0| 52 20 52 45 51 55 45 53 | 54 20 6d 65 73 73 61 67 |R REQUES|T messag|
|00003fb0| 65 2c 20 35 2e 35 2e 35 | 29 2e 20 20 54 68 65 20 |e, 5.5.5|). The |
|00003fc0| 6d 65 73 73 61 67 65 73 | 20 64 65 74 65 72 6d 69 |messages| determi|
|00003fd0| 6e 65 20 74 68 65 20 75 | 73 65 20 6f 66 20 0a 73 |ne the u|se of .s|
|00003fe0| 79 6e 63 68 72 6f 6e 6f | 75 73 20 6d 6f 64 65 20 |ynchrono|us mode |
|00003ff0| 62 79 20 62 6f 74 68 20 | 53 43 53 49 20 64 65 76 |by both |SCSI dev|
|00004000| 69 63 65 73 20 61 6e 64 | 20 65 73 74 61 62 6c 69 |ices and| establi|
|00004010| 73 68 20 61 20 52 45 51 | 2f 41 43 4b 20 6f 66 66 |sh a REQ|/ACK off|
|00004020| 73 65 74 20 61 6e 64 20 | 61 20 0a 74 72 61 6e 73 |set and |a .trans|
|00004030| 66 65 72 20 70 65 72 69 | 6f 64 2e 0a 0a 0a 20 20 |fer peri|od.... |
|00004040| 54 68 65 20 52 45 51 2f | 41 43 4b 20 6f 66 66 73 |The REQ/|ACK offs|
|00004050| 65 74 20 73 70 65 63 69 | 66 69 65 73 20 74 68 65 |et speci|fies the|
|00004060| 20 6d 61 78 69 6d 75 6d | 20 6e 75 6d 62 65 72 20 | maximum| number |
|00004070| 6f 66 20 52 45 51 20 70 | 75 6c 73 65 73 20 74 68 |of REQ p|ulses th|
|00004080| 61 74 20 63 61 6e 20 62 | 65 20 0a 73 65 6e 74 20 |at can b|e .sent |
|00004090| 62 79 20 74 68 65 20 74 | 61 72 67 65 74 20 69 6e |by the t|arget in|
|000040a0| 20 61 64 76 61 6e 63 65 | 20 6f 66 20 74 68 65 20 | advance| of the |
|000040b0| 6e 75 6d 62 65 72 20 6f | 66 20 41 43 4b 20 70 75 |number o|f ACK pu|
|000040c0| 6c 73 65 73 20 72 65 63 | 65 69 76 65 64 20 66 72 |lses rec|eived fr|
|000040d0| 6f 6d 20 74 68 65 20 0a | 69 6e 69 74 69 61 74 6f |om the .|initiato|
|000040e0| 72 2c 20 65 73 74 61 62 | 6c 69 73 68 69 6e 67 20 |r, estab|lishing |
|000040f0| 61 20 70 61 63 69 6e 67 | 20 6d 65 63 68 61 6e 69 |a pacing| mechani|
|00004100| 73 6d 2e 20 20 49 66 20 | 74 68 65 20 6e 75 6d 62 |sm. If |the numb|
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|00004120| 20 0a 65 78 63 65 65 64 | 73 20 74 68 65 20 6e 75 | .exceed|s the nu|
|00004130| 6d 62 65 72 20 6f 66 20 | 41 43 4b 20 70 75 6c 73 |mber of |ACK puls|
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|00004150| 4b 20 6f 66 66 73 65 74 | 2c 20 74 68 65 20 74 61 |K offset|, the ta|
|00004160| 72 67 65 74 20 73 68 61 | 6c 6c 20 6e 6f 74 20 0a |rget sha|ll not .|
|00004170| 61 73 73 65 72 74 20 52 | 45 51 20 75 6e 74 69 6c |assert R|EQ until|
|00004180| 20 74 68 65 20 6e 65 78 | 74 20 41 43 4b 20 70 75 | the nex|t ACK pu|
|00004190| 6c 73 65 20 69 73 20 72 | 65 63 65 69 76 65 64 2e |lse is r|eceived.|
|000041a0| 20 20 41 20 72 65 71 75 | 69 72 65 6d 65 6e 74 20 | A requ|irement |
|000041b0| 66 6f 72 20 73 75 63 63 | 65 73 73 66 75 6c 20 0a |for succ|essful .|
|000041c0| 63 6f 6d 70 6c 65 74 69 | 6f 6e 20 6f 66 20 74 68 |completi|on of th|
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|000041e0| 74 68 61 74 20 74 68 65 | 20 6e 75 6d 62 65 72 20 |that the| number |
|000041f0| 6f 66 20 41 43 4b 20 61 | 6e 64 20 52 45 51 20 70 |of ACK a|nd REQ p|
|00004200| 75 6c 73 65 73 20 62 65 | 20 0a 65 71 75 61 6c 2e |ulses be| .equal.|
|00004210| 20 0a 0a 20 20 54 68 65 | 20 74 61 72 67 65 74 20 | .. The| target |
|00004220| 73 68 61 6c 6c 20 61 73 | 73 65 72 74 20 74 68 65 |shall as|sert the|
|00004230| 20 52 45 51 20 73 69 67 | 6e 61 6c 20 66 6f 72 20 | REQ sig|nal for |
|00004240| 61 20 6d 69 6e 69 6d 75 | 6d 20 6f 66 20 61 6e 20 |a minimu|m of an |
|00004250| 61 73 73 65 72 74 69 6f | 6e 20 70 65 72 69 6f 64 |assertio|n period|
|00004260| 2e 20 0a 54 68 65 20 74 | 61 72 67 65 74 20 73 68 |. .The t|arget sh|
|00004270| 61 6c 6c 20 77 61 69 74 | 20 61 74 20 6c 65 61 73 |all wait| at leas|
|00004280| 74 20 74 68 65 20 67 72 | 65 61 74 65 72 20 6f 66 |t the gr|eater of|
|00004290| 20 61 20 74 72 61 6e 73 | 66 65 72 20 70 65 72 69 | a trans|fer peri|
|000042a0| 6f 64 20 66 72 6f 6d 20 | 74 68 65 20 6c 61 73 74 |od from |the last|
|000042b0| 20 0a 74 72 61 6e 73 69 | 74 69 6f 6e 20 6f 66 20 | .transi|tion of |
|000042c0| 52 45 51 20 74 6f 20 74 | 72 75 65 20 6f 72 20 61 |REQ to t|rue or a|
|000042d0| 20 6d 69 6e 69 6d 75 6d | 20 6f 66 20 61 20 6e 65 | minimum| of a ne|
|000042e0| 67 61 74 69 6f 6e 20 70 | 65 72 69 6f 64 20 66 72 |gation p|eriod fr|
|000042f0| 6f 6d 20 74 68 65 20 6c | 61 73 74 20 0a 74 72 61 |om the l|ast .tra|
|00004300| 6e 73 69 74 69 6f 6e 20 | 6f 66 20 52 45 51 20 74 |nsition |of REQ t|
|00004310| 6f 20 66 61 6c 73 65 20 | 62 65 66 6f 72 65 20 61 |o false |before a|
|00004320| 73 73 65 72 74 69 6e 67 | 20 74 68 65 20 52 45 51 |sserting| the REQ|
|00004330| 20 73 69 67 6e 61 6c 2e | 0a 0a 20 20 54 68 65 20 | signal.|.. The |
|00004340| 69 6e 69 74 69 61 74 6f | 72 20 73 68 61 6c 6c 20 |initiato|r shall |
|00004350| 73 65 6e 64 20 6f 6e 65 | 20 70 75 6c 73 65 20 6f |send one| pulse o|
|00004360| 6e 20 74 68 65 20 41 43 | 4b 20 73 69 67 6e 61 6c |n the AC|K signal|
|00004370| 20 66 6f 72 20 65 61 63 | 68 20 52 45 51 20 70 75 | for eac|h REQ pu|
|00004380| 6c 73 65 20 0a 72 65 63 | 65 69 76 65 64 2e 20 20 |lse .rec|eived. |
|00004390| 54 68 65 20 69 6e 69 74 | 69 61 74 6f 72 20 73 68 |The init|iator sh|
|000043a0| 61 6c 6c 20 61 73 73 65 | 72 74 20 74 68 65 20 41 |all asse|rt the A|
|000043b0| 43 4b 20 73 69 67 6e 61 | 6c 20 66 6f 72 20 61 20 |CK signa|l for a |
|000043c0| 6d 69 6e 69 6d 75 6d 20 | 6f 66 20 61 6e 20 0a 61 |minimum |of an .a|
|000043d0| 73 73 65 72 74 69 6f 6e | 20 70 65 72 69 6f 64 2e |ssertion| period.|
|000043e0| 20 20 54 68 65 20 69 6e | 69 74 69 61 74 6f 72 20 | The in|itiator |
|000043f0| 73 68 61 6c 6c 20 77 61 | 69 74 20 61 74 20 6c 65 |shall wa|it at le|
|00004400| 61 73 74 20 74 68 65 20 | 67 72 65 61 74 65 72 20 |ast the |greater |
|00004410| 6f 66 20 61 20 74 72 61 | 6e 73 66 65 72 20 0a 70 |of a tra|nsfer .p|
|00004420| 65 72 69 6f 64 20 66 72 | 6f 6d 20 74 68 65 20 6c |eriod fr|om the l|
|00004430| 61 73 74 20 74 72 61 6e | 73 69 74 69 6f 6e 20 6f |ast tran|sition o|
|00004440| 66 20 41 43 4b 20 74 6f | 20 74 72 75 65 20 6f 72 |f ACK to| true or|
|00004450| 20 66 6f 72 20 61 20 6d | 69 6e 69 6d 75 6d 20 6f | for a m|inimum o|
|00004460| 66 20 61 20 6e 65 67 61 | 74 69 6f 6e 20 0a 70 65 |f a nega|tion .pe|
|00004470| 72 69 6f 64 20 66 72 6f | 6d 20 74 68 65 20 6c 61 |riod fro|m the la|
|00004480| 73 74 20 74 72 61 6e 73 | 69 74 69 6f 6e 20 6f 66 |st trans|ition of|
|00004490| 20 41 43 4b 20 74 6f 20 | 66 61 6c 73 65 20 62 65 | ACK to |false be|
|000044a0| 66 6f 72 65 20 61 73 73 | 65 72 74 69 6e 67 20 74 |fore ass|erting t|
|000044b0| 68 65 20 41 43 4b 20 0a | 73 69 67 6e 61 6c 2e 0a |he ACK .|signal..|
|000044c0| 0a 20 20 49 66 20 49 2f | 4f 20 69 73 20 74 72 75 |. If I/|O is tru|
|000044d0| 65 20 28 74 72 61 6e 73 | 66 65 72 20 74 6f 20 74 |e (trans|fer to t|
|000044e0| 68 65 20 69 6e 69 74 69 | 61 74 6f 72 29 2c 20 74 |he initi|ator), t|
|000044f0| 68 65 20 74 61 72 67 65 | 74 20 73 68 61 6c 6c 20 |he targe|t shall |
|00004500| 66 69 72 73 74 20 64 72 | 69 76 65 20 0a 44 42 28 |first dr|ive .DB(|
|00004510| 37 2d 30 2c 50 29 20 74 | 6f 20 74 68 65 69 72 20 |7-0,P) t|o their |
|00004520| 64 65 73 69 72 65 64 20 | 76 61 6c 75 65 73 2c 20 |desired |values, |
|00004530| 77 61 69 74 20 61 74 20 | 6c 65 61 73 74 20 6f 6e |wait at |least on|
|00004540| 65 20 64 65 73 6b 65 77 | 20 64 65 6c 61 79 20 70 |e deskew| delay p|
|00004550| 6c 75 73 20 6f 6e 65 20 | 0a 63 61 62 6c 65 20 73 |lus one |.cable s|
|00004560| 6b 65 77 20 64 65 6c 61 | 79 2c 20 74 68 65 6e 20 |kew dela|y, then |
|00004570| 61 73 73 65 72 74 20 52 | 45 51 2e 20 20 44 42 28 |assert R|EQ. DB(|
|00004580| 37 2d 30 2c 50 29 20 73 | 68 61 6c 6c 20 62 65 20 |7-0,P) s|hall be |
|00004590| 68 65 6c 64 20 76 61 6c | 69 64 20 66 6f 72 20 61 |held val|id for a|
|000045a0| 20 0a 6d 69 6e 69 6d 75 | 6d 20 6f 66 20 6f 6e 65 | .minimu|m of one|
|000045b0| 20 64 65 73 6b 65 77 20 | 64 65 6c 61 79 20 70 6c | deskew |delay pl|
|000045c0| 75 73 20 6f 6e 65 20 63 | 61 62 6c 65 20 73 6b 65 |us one c|able ske|
|000045d0| 77 20 64 65 6c 61 79 20 | 70 6c 75 73 20 6f 6e 65 |w delay |plus one|
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|000061e0| 20 0a 52 45 53 45 54 20 | 6f 70 74 69 6f 6e 2c 20 | .RESET |option, |
|000061f0| 75 70 6f 6e 20 64 65 74 | 65 63 74 69 6f 6e 20 6f |upon det|ection o|
|00006200| 66 20 74 68 65 20 52 45 | 53 45 54 20 63 6f 6e 64 |f the RE|SET cond|
|00006210| 69 74 69 6f 6e 2c 20 73 | 68 61 6c 6c 3a 0a 0a 20 |ition, s|hall:.. |
|00006220| 20 28 31 29 20 43 6c 65 | 61 72 20 61 6c 6c 20 75 | (1) Cle|ar all u|
|00006230| 6e 63 6f 6d 70 6c 65 74 | 65 64 20 63 6f 6d 6d 61 |ncomplet|ed comma|
|00006240| 6e 64 73 0a 20 20 28 32 | 29 20 52 65 6c 65 61 73 |nds. (2|) Releas|
|00006250| 65 20 61 6c 6c 20 53 43 | 53 49 20 64 65 76 69 63 |e all SC|SI devic|
|00006260| 65 20 72 65 73 65 72 76 | 61 74 69 6f 6e 73 0a 20 |e reserv|ations. |
|00006270| 20 28 33 29 20 52 65 74 | 75 72 6e 20 61 6e 79 20 | (3) Ret|urn any |
|00006280| 53 43 53 49 20 64 65 76 | 69 63 65 20 6f 70 65 72 |SCSI dev|ice oper|
|00006290| 61 74 69 6e 67 20 6d 6f | 64 65 73 20 28 4d 4f 44 |ating mo|des (MOD|
|000062a0| 45 20 53 45 4c 45 43 54 | 2c 20 50 52 45 56 45 4e |E SELECT|, PREVEN|
|000062b0| 54 2f 41 4c 4c 4f 57 20 | 0a 4d 45 44 49 55 4d 20 |T/ALLOW |.MEDIUM |
|000062c0| 52 45 4d 4f 56 41 4c 20 | 63 6f 6d 6d 61 6e 64 73 |REMOVAL |commands|
|000062d0| 2c 20 65 74 63 29 20 74 | 6f 20 74 68 65 69 72 20 |, etc) t|o their |
|000062e0| 64 65 66 61 75 6c 74 20 | 63 6f 6e 64 69 74 69 6f |default |conditio|
|000062f0| 6e 73 2e 0a 0a 20 20 20 | 20 20 02 35 2e 32 2e 32 |ns... | .5.2.2|
|00006300| 2e 32 20 22 53 6f 66 74 | 22 20 52 45 53 45 54 20 |.2 "Soft|" RESET |
|00006310| 4f 70 74 69 6f 6e 2e 02 | 20 20 53 43 53 49 20 64 |Option..| SCSI d|
|00006320| 65 76 69 63 65 73 20 74 | 68 61 74 20 69 6d 70 6c |evices t|hat impl|
|00006330| 65 6d 65 6e 74 20 74 68 | 65 20 22 73 6f 66 74 22 |ement th|e "soft"|
|00006340| 20 0a 52 45 53 45 54 20 | 6f 70 74 69 6f 6e 2c 20 | .RESET |option, |
|00006350| 75 70 6f 6e 20 64 65 74 | 65 63 74 69 6f 6e 20 6f |upon det|ection o|
|00006360| 66 20 74 68 65 20 52 45 | 53 45 54 20 63 6f 6e 64 |f the RE|SET cond|
|00006370| 69 74 69 6f 6e 2c 20 73 | 68 61 6c 6c 3a 0a 0a 20 |ition, s|hall:.. |
|00006380| 20 28 31 29 20 41 74 74 | 65 6d 70 74 20 74 6f 20 | (1) Att|empt to |
|00006390| 63 6f 6d 70 6c 65 74 65 | 20 61 6e 79 20 75 6e 63 |complete| any unc|
|000063a0| 6f 6d 70 6c 65 74 65 64 | 20 63 6f 6d 6d 61 6e 64 |ompleted| command|
|000063b0| 73 20 74 68 61 74 20 77 | 65 72 65 20 66 75 6c 6c |s that w|ere full|
|000063c0| 79 20 69 64 65 6e 74 69 | 66 69 65 64 0a 20 20 28 |y identi|fied. (|
|000063d0| 32 29 20 50 72 65 73 65 | 72 76 65 20 61 6c 6c 20 |2) Prese|rve all |
|000063e0| 53 43 53 49 20 64 65 76 | 69 63 65 20 72 65 73 65 |SCSI dev|ice rese|
|000063f0| 72 76 61 74 69 6f 6e 73 | 0a 0a 20 20 28 33 29 20 |rvations|.. (3) |
+--------+-------------------------+-------------------------+--------+--------+
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