Seagate Ultra 160 manual

Parallel SCSI Interface Ultra 160 Ultra 320[...]

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Parallel SCSI Interface Ultra 160 Ultra 320[...]

©2006, Seagate T echnology LLC All ri ghts rese rved Publication number: 1002 93069, Rev . A March 2006 Seagate and Seagate T echnology are register ed trad emarks of Seagate T echnology LLC. SeaT o ols, SeaFONE, Se aBOARD, SeaTDD, and the W ave logo are either registered trad e - marks or trademarks of Seaga te T echnology LLC. Other product name[...]

Parallel SCSI Interface Product Manual, Rev. A iii Revision st atus summary sheet Revision Date Writer/Engineer Sheet s Affected Rev . A 03/27/06 C. Chalup a/G . Houlder All.[...]

iv Parallel SCSI Interface Product Manual, Rev. A[...]

Parallel SCSI Interface Product Manual, Rev. A v Table of Contents 1.0 Interface requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 How to use this interface manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

vi Parallel SCSI Interface Product Manual, Rev. A 2.5.35 Receive setup time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2.5.36 Receive REQ(ACK) period tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2.5.37 Receive REQ assertion period[...]

Parallel SCSI Interface Product Manual, Rev. A vii 2.12.8.3 QA S_REQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 2.12.8.4 HO LD_MCS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 2.12.8.5 WR_FLO W . . . . . [...]

viii Parallel SCSI Interface Product Manual, Rev. A 3.7.1 DATA phase overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 3.7.2 DT DATA IN phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 3.7.3 DT DATA OUT phase . .[...]

Parallel SCSI Interface Product Manual, Rev. A ix 4.3.16 SYNCHRO NOUS DATA TRANSFER REQ UEST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 4.3.16.1 Target initiated SDTR negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 4.3.16.2 Initiator initiated SDTR negotiation . . . . . . . . . . [...]

x Parallel SCSI Interface Product Manual, Rev. A 7.3.1 Status precedence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 7.4 Command examples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 7.4.1 Single comman[...]

Parallel SCSI Interface Product Manual, Rev. A xi List of Figures Figure 1. SCSI client-server model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 2. Voltage and current definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 8 F[...]

xii Parallel SCSI Interface Product Manual, Rev. A[...]

Parallel SCSI Interface Product Manual, Rev. A 1 1.0 Interface requirements 1.1 How to use this interface manual This manual pr ovides a descr iption of the SC SI 1 interface protocol and some general timing information as implemented by Seagate p roducts. T he features described in this manual are typically r eferred to as “Ultra160 SCSI” or ?[...]

2 Parallel SCSI Interface Product Manual, Rev. A 1.1.1 Scope of SCSI standards Figure 1 uses a represent ative set of specifications to show the functional partitio ns and the relationship s among SCSI sta ndards applicable to drives covered by this manual. Figure 1. Functional scope o f SCSI 1 standards The functional areas define the sco pe of ea[...]

Parallel SCSI Interface Product Manual, Rev. A 3 1.1.2 A pplicable st andards The following ANSI st andards should be r e ferenced for more det ails about SCSI system standards o f opera - tion: • SCSI Architec ture Model - 4 (SAM-4), T 10/1683-D • SCSI Enclosure Services - 2 (SES-2), T10/1559-D • SCSI Block Commands - 3 (SBC-3), T10/1215-D ?[...]

4 Parallel SCSI Interface Product Manual, Rev. A Figure 2. SCSI client-server model 1.2.1 Glo ssary aborted command —A SCSI command that has been ended by abor ting the task crea ted to execute it. ACA —Auto Contingent Allegiance (see below). additional sense code — a combination of the ADDITIONAL SENSE CODE and ADDITONAL SENSE CODE QUALIFIER[...]

Parallel SCSI Interface Product Manual, Rev. A 5 command descriptor block —A structur e used to commun icate a command fr om an application clie nt to a device server . Command structures of 6, 10, 12, or 16 bytes ar e used, but a new variable length command structure has recently been intro duced. completed command —A command that has ended by[...]

6 Parallel SCSI Interface Product Manual, Rev. A double transition (DT) —The latching of dat a on both the assertion edge and the negated edge of the REQ or ACK signals. driver —The circuitry used to contr ol the state of the bus. enabled t ask st ate —The state of a t ask that may complete at any time . Alternatively , the stat e of a task t[...]

Parallel SCSI Interface Product Manual, Rev. A 7 I/O operation —An operation defined by an unlinked SCSI co mmand, a series of linke d SCSI commands or a task manageme nt function. I/O process —An I/O process consist s of one initial connection or , if information units are enabled, the establishment of a nexus, and a zero or more physical or l[...]

8 Parallel SCSI Interface Product Manual, Rev. A nexus —A relationship between a SCSI initiato r port and a SCSI target port, logical unit, or queue t ag that begins with an initial connection and ends with th e comple tion of the associated I/O process. This relationship is formed as the result of a t ask. object —An architectu ral abstraction[...]

Parallel SCSI Interface Product Manual, Rev. A 9 protocol servic e request —A call to the lower level pr otocol service layer to begin a prot ocol service transac - tion. protocol servic e response —A reply from the upper level protocol laye r in response to a protocol service indi - cation. quick arbitra t ion and selection proce ss (QAS) —Q[...]

10 Parallel SCSI Interface Product Manual, Rev. A service delivery tra nsaction —A request or response sent throug h the service delivery subsystem. signal —(n) A detectable asynchronous event possibly acco mpanied by descriptive data and parameters. (v) The act of generating such an even t. single trans ition (ST) —The latching of data only [...]

Parallel SCSI Interface Product Manual, Rev. A 11 third-pa rty command —A SCSI command which requires a logical unit within the targe t device to assume the initiator role and send a SCSI command to a SCSI target por t device. transaction —A cooper ative interaction between two o bjects, involving the exch ange of information or the exe - cutio[...]

12 Parallel SCSI Interface Product Manual, Rev. A 1.3 Physical interface cha racteristics The physical interface characteristi cs (cables, connectors, electrical desc riptions, termination requ irements, etc.) for the drives cover ed by this Interface Manual ar e found in each individual drive’s Produ ct Manual, since these featur es are not the [...]

Parallel SCSI Interface Product Manual, Rev. A ) 13 2.0 SCSI bus This manual discusses only the “lo g ical” and timing char acteristics of the SCSI system and interface. A genera l description of th e SCSI bus physical characteristics (voltages, connector configurations, pinouts, etc.) are given in the indi vidual drive’ s Product Manual, in [...]

14 Parallel SCSI Interface Product Manual, R ev. A ) The Host Adapter/Initiator must be identified by on e of the 16 SCSI Device IDs (usually 7, which is highest arbi - tration priority). Make sure that none of t he devices on the SCSI bus have duplicate IDs. Certain SCSI bus functions are assigned to the initiato r and cert ain SCSI bus functions [...]

Parallel SCSI Interface Product Manual, Rev. A ) 15 2.1 SCSI bus signals overview Information transfer on the SCSI bu s is allowed between only two SCSI devices at any given time except dur - ing MESSAGE IN PHASE when QAS is enabled. All SCSI devices that ha ve QAS enabled are required to monitor messages during a MESSAGE IN PHASE for a QAS REQUEST[...]

16 Parallel SCSI Interface Product Manual, R ev. A ) During the SELECTION PHASE, RESELECTION PH ASE, ST DA T A PHASE, COMMAND PHASE, MESSAGE PHASE, and ST A TUS PHASE, this signal is referred to as DB(P_CRCA) and is sour ced by the SCSI device port driving the Da ta Bus. Th e DB(P_CRCA) signal is as sociat ed with the DB(7-0 ) signals and is used t[...]

Parallel SCSI Interface Product Manual, Rev. A ) 17 When information unit transfers are enabled, the P1 si gnal shall be cont inuously negated by the SCSI device driving the D B(15-0) sign als and shall b e ignored by the SCSI d evice receiving the DB(15-0 ) signals dur ing DT DA T A phases. During DT DA T A phases when info rmation unit transfers [...]

18 Parallel SCSI Interface Product Manual, R ev. A ) Figure 3. V olt age and current definitions Figure 4 defines the signa ling sense of the voltages ap peari ng on the – signal and + signal lines as follows: a. The – signal ter minal of the dr iver shall be ne gative with respect to the + signal terminal for an asserte d state. b. The – sig[...]

Parallel SCSI Interface Product Manual, Rev. A ) 19 2.4 Signal sources Ta b l e 3 indicates the type of SCSI device allowed to sour ce each signal. No attempt is made to show if the source is driving asser ted, driving negated , or is released. All SCSI device drivers th at are not active source s shall be in the high-impedan ce state. The RST sign[...]

20 Parallel SCSI Interface Product Manual, R ev. A ) 2.5 SCSI bus timing Unless otherwise indicated, the delay time measuremen t s for each SCSI device, defined in p aragraphs 2.5.1 through 2.5.60 shall be calculated from signal conditions exis ting at that SCSI devi ce’ s own SCSI bus connec - tion. Thus, these measureme nts (excep t skew delay)[...]

Parallel SCSI Interface Product Manual, Rev. A ) 21 T able 5: SCSI bus dat a and information phase ST timin g values [1] SCSI bus timing values specified by the maximu m transfer rate for the given range shall apply even if a slower transfer ra te within the given range is ne gotiated. [2] Cable skew is measured at each SCSI device conn ection with[...]

22 Parallel SCSI Interface Product Manual, R ev. A ) [2] Cable skew is measured at each SCSI device conn ection with in the same bus segment with the transmit- ted skew subtracted from the received skew . [3] Calculated assuming timing budget shown in T able 9. [4] Measured at the receiver term inal using clean input signals with 500 mV peak amplit[...]

Parallel SCSI Interface Product Manual, Rev. A ) 23 T able 7: T ransmit SCSI bus dat a and information phase DT timing values [1] SCSI bus timing values specified by the maximu m transfer rate for the given range shall apply even if a slower transfer ra te within the given range is ne gotiated. [2] See Section 2.6 for measur ement poin ts for the t[...]

24 Parallel SCSI Interface Product Manual, R ev. A ) T able 8: Receive SCSI bu s data and information phas e DT timing values [1] SCSI bus timing values specified by the maximu m transfer rate for the given range shall apply even if a slower transfer ra te within the given range is ne gotiated. [2] See Section 2.6 for measurement poin ts for the ti[...]

Parallel SCSI Interface Product Manual, Rev. A ) 25 T able 9: SCSI Fast -160 and fast 320 non-compensat able timing budget in nanoseconds Item Fast-160 Fast-320 Comment s REQ(ACK) period 12.5 6.25 From T able 7 T ransfer perio d 6.25 3.125 REQ(ACK) period / 2 T ransmitter and receive r errors: To t a l Errors Post Compen sation To t a l Errors Post[...]

26 Parallel SCSI Interface Product Manual, R ev. A ) 2.5.1 Arbitration de lay The minimum time a SCSI device shall wait from asserting BSY for arbitrat ion until the data bus can be exa m - ined to see if arbitration has been won (see Sectio n 3.1.2 ). There is no maximum time. 2.5.2 A T N transmit setup time When information unit transfers are not[...]

Parallel SCSI Interface Product Manual, Rev. A ) 27 When information unit transfers are bein g used with syn chronous transfers, the A TN receive setup time is the minimum ti me required at the receiv er between the assertion of the A TN signal an d the negatio n of the ACK signal corresponding to the la st iuCRC transfer of an info rmation unit to[...]

28 Parallel SCSI Interface Product Manual, R ev. A ) 2.5.12 De-skewed dat a valid window The minimum difference in time a llowed between the rising or falling ed ge of a “1010...” pattern on the DA T BUS or DB(P1) and it s clocking signal on the ACK or RE Q signal as measured a t their zero-crossin g points afte r skew compensatio n is applied [...]

Parallel SCSI Interface Product Manual, Rev. A ) 29 2.5.21 Dat a releas e delay The maximum time for a SCSI initiator port to releas e the DA T A BUS, DB(P_CRCA), and/or DB(P1) sig nals, following the transition of the I/O signal from false to true. 2.5.22 DIFFSENS voltage filter time The minimum time DIFFSENS volt age shall be sensed co ntinuously[...]

30 Parallel SCSI Interface Product Manual, R ev. A ) DB(P1) signals. For p aced dat a transfers negative valu es as measured at the d evice conn ector are ac commo - dated by skew compensation in the receiver . Receive hold time measur ed at the device connecto r shall not exceed the skew correc tion range. 2.5.32 Receive internal h old time The mi[...]

Parallel SCSI Interface Product Manual, Rev. A ) 31 2.5.40 Receiver amplitud e time skew The maximum time shif t of SCSI bus si gnals caused by the dif f erence in re ceiver switching de lay of a minimum amplitude signal ver sus a maximum amplitu de signal. 2.5.41 REQ(ACK) period The REQ(ACK) perio d during synchr onous transfer s or paced transfer[...]

32 Parallel SCSI Interface Product Manual, R ev. A ) pensation. 2.5.49 Skew correction range The minimum skew correction capability of the receiver of a signal on the DA T A BUS or DB(P1) relative to the ACK or REQ signal as measured at the receiver’s conn ector . The skew correction range shall be equal to: +/– [(transmitter c hip skew) + (cab[...]

Parallel SCSI Interface Product Manual, Rev. A ) 33 The minimum time that a SCSI t arget port shall negate the REQ signal while using synchronous transfers or paced transfers, pr ovided it is not transitioning P_CRCA during dat a grou p transfers. Also, the minimum tim e that a SCSI initiator port shall negate the ACK signal while using synch ronou[...]

34 Parallel SCSI Interface Product Manual, R ev. A ) SE SCSI devices with data transfer rates up to a nd including Fast-20 shall use the measur ement points defined in Section 9 of ANSI standard SPI-4, for the m easurement of the timing values. The rise and fall times for the SE REQ/ACK signals shall be nominally the sa me as for the SE Dat a, DB(P[...]

Parallel SCSI Interface Product Manual, Rev. A ) 35 Figure 8 shows an example of transfers with a negotiated tr ansfer period of 6.25 ns at the receiving SCSI device’s connector . Ther e is no difference as to when data is latched on p aced transfers, however , the relation - ship between the dat a and REQ or ACK is requ ired to be ad justed in t[...]

36 Parallel SCSI Interface Product Manual, R ev. A ) Figure 7. DT synchronous trans fer example Figure 8. Paced transfer example 2.8 Paced transfer on a SCSI bus A SCSI bus that support s paced transfers has add itional dr iver and receiver functions re quired over those used with synchronous transfe rs or asynchronous transfers . These functions i[...]

Parallel SCSI Interface Product Manual, Rev. A ) 37 The receiver skew compensa tion and clock shif ting adjust the timing relationship between the clocking signal (i.e., REQ or ACK) and the signals bei ng clocked (e.g., the data bus sign al s). Th at adjustment causes the clock signal to align with the middle of the signals being cl ocked when thos[...]

38 Parallel SCSI Interface Product Manual, R ev. A ) 2.10 ST DA T A phase parallel transfers The format of dat a transmitted during ST DA T A phases consists of dat a and protection. Parity generation and checking give some error detection protection in the ST phase data. 2.1 1 DT DA T A phase parallel transfers During DT DA T A phases, communicati[...]

Parallel SCSI Interface Product Manual, Rev. A ) 39 The iuCRC shall be used to prot ect all SPI inform ation un its. The SCSI device that origina tes the SPI informa - tion unit sends the necessar y pad bytes and iuCRC fields. An iuCRC interval may also be specif ied. The iuCRC interval specifies the number of bytes transfer red before pad bytes (i[...]

40 Parallel SCSI Interface Product Manual, R ev. A ) If the responding negotiation message contains values the origi nating port does not support, the orig inating port shall respond with a MESSAGE REJE CT message. 2.12.2 When to negotiate Each port shall maint ain a negotiation required flag for each other po rt. A port shall set it s negotiation [...]

Parallel SCSI Interface Product Manual, Rev. A ) 41 When negotia ting, the respon ding port sha ll respond with values that are a subset o f the values in the ori ginat - ing message as indicated in T able 12 (e.g., if the origina t ing message requ ests a REQ/ACK of fset of 10h, the responding m essage has a REQ/ACK offset field se t to 10h or low[...]

42 Parallel SCSI Interface Product Manual, R ev. A ) 2.12.4 T ra nsfer agreeme nt s The transfer agreeme nts that are in ef fect for various combinations of field values are describe d in T able 13 . T able 13: T ransfer agreemen ts T ransfer agreement REQ/ACK offset T ransfer period factor T ransfer wid th exponent DT_REQ IU_REQ QAS_REQ All other [...]

Parallel SCSI Interface Product Manual, Rev. A ) 43 2.12.5 T ran sfer period fa ctor The T ransfer Period Factor field select s the transfer per iod and determin es which transfer rate’s timing values in T ables 5 , 6 , 7 , and 8 shall be honored, provided that REQ/ACK OFFSET is gr eater than 00h. The field val - ues are defined in T able 14 . Ta[...]

44 Parallel SCSI Interface Product Manual, R ev. A ) 2.12.6 REQ/ACK offset The REQ/ACK OFFSET field de termines the maxim um num ber of REQs allowed to be outst anding before a correspond ing ACK is received at the SCS I target port during synchronou s or paced transfers. For ST synchro - nous transfers the REQ/ACK of fset is the number of REQ asse[...]

Parallel SCSI Interface Product Manual, Rev. A ) 45 2.12.8 Protocol options The protocol options fie lds affect th e protocol used betwee n the ports. The SCSI t arget port uses the protocol options bits to indicate to the SCSI in itiator port if it agrees to enable th e requested pr otocol options. Except for the PCOMP_EN bit, the SCSI target po r[...]

46 Parallel SCSI Interface Product Manual, R ev. A ) Ta b l e 19 de scribes the bus phas es resulting from IU_REQ changes. 2.12.8.2 DT_R EQ The SCSI initiator port shall set DT_REQ to one to requ es t that DT DA T A phases be enabled. In response, the SCSI target port shall set DT_REQ to one if it agre es to use DT DA T A phases or zero if it does [...]

Parallel SCSI Interface Product Manual, Rev. A ) 47 Ta b l e 20 defines valid co mbinations of HOLD_MCS and other fie lds. 2.12.8.5 WR_F LOW The SCSI initiator port shall set WR _F LOW to one to indicate that the SCSI target port should enable write flow control durin g write streamin g. In response, the SCSI targ et port shall set WR_FLOW to one i[...]

48 Parallel SCSI Interface Product Manual, R ev. A ) 2.12.9 Negotiable field combin ations Not all combinations of the negotiable fields ar e valid. On ly the combinations defined in T able 20 shall be allowed. All other combinations of th e listed fields are reserved. T able 20: V alid negotiable field combinations T ransfer period factor REQ/ ACK[...]

Parallel SCSI Interface Product Manual, Rev. A ) 49 2.12.10 Messa ge restrictio ns PPR may be originated by SCSI initiator port s but shall not be originated by SCSI t arget ports. If bus expande rs are present, SCSI initiato r port s should only use PPR when requesting values not att ainable via WDTR and SDTR (e.g., setting any pr otocol option bi[...]

50 Parallel SCSI Interface Product Manual, R ev. A )[...]

Parallel SCSI Interface Product Manual, Rev. A 51 3.0 Logical characteristics The operations of th e SCSI bus as described in this se ction are supported by the dr ive as specified in each individual dr ive’s Product Manu al. The dr ive always functions as the target unless oth e rwise stated. 3.1 SCSI bus phases overview The drive responds to th[...]

52 Parallel SCSI Interface Product Manual, Rev. A a. af ter any bus reset event. b. af ter a transceiver mode change reset event. c. after an Abort T ask managem ent function is successfully re ceived by a SCSI target port; d. after an Abort T ask Set ma nagement fu nction is successfully received by a SCSI target port; e. af ter a Clear T ask Set [...]

Parallel SCSI Interface Product Manual, Rev. A 53 SCSI devices with arbitration fair ness enabled shall main ta in a fairness register that records the SCSI IDs of devices that ne ed a chance to arbi trate (see Se ction 3.4 ). Fa irness in normal arbitra tion is enabled in target s by the Disconnect-Reconne ct mode p age (see Seagate SCSI Command R[...]

54 Parallel SCSI Interface Product Manual, Rev. A 3.1.2.2 QAS p rotocol Quick Arbitration and Selection (QAS) a llows a SCSI target port with an information unit tran sfer agreement in effect an d QAS enabled (see Section 4.3.12 ) that is currently c onnected to a SCSI initiator port that has info r - mation unit transfers enabled and QAS ena bled [...]

Parallel SCSI Interface Product Manual, Rev. A 55 4. If the SCSI initiat or creates an att ention condition, the SCSI target port sh all go to a MESS AGE OUT phase, receive all the message by te s, and cause an unexpected bus free by generating a BUS FREE phase (see Section 3.1.1.1 on p age 51 ). 5. If the SCSI target port de tects the SEL signal b[...]

56 Parallel SCSI Interface Product Manual, Rev. A Refer to Section 3.4 for a descript ion of the fairness algori thm which applies during SELECTION and RESE - LECTION phases. 3.2.1 Select ion overvi ew The SCSI device that won a normal arbitration has both the BSY and SEL si gnals asserted an d has delayed at least one bus clear delay plus a bus se[...]

Parallel SCSI Interface Product Manual, Rev. A 57 3.2.1.1. 4 Se lection usin g attent ion condition timeout procedure T wo optional selec tion timeout proc edures are sp ecified for clearing the SCSI b us if the initiator waits a mini - mum of one selection ti meout delay and th ere has been no BSY signal re sponse from the target: • Optionally ,[...]

58 Parallel SCSI Interface Product Manual, Rev. A (a) Optionally , the initiator shall assert the RST sign al (see Section 5.3); (b) Optionally , the initiator shall continue asserting the SEL signal and sh all release the Data Bus, DB(P_CRCA), or DB(P1). If the initia tor has not detected the BSY sig nal to be true af ter at least one selection ab[...]

Parallel SCSI Interface Product Manual, Rev. A 59 glitch may cause the BSY signal to appear false for up to a round-trip prop agatio n delay following the release of the BSY signal by the in itiator . This is the reason why the BUS FREE phase is recognized only after both the BSY and SEL signals are continuo usly false for a minimum of one bus sett[...]

60 Parallel SCSI Interface Product Manual, Rev. A 3.5 Information transfer phases The COMMAND, DA T A, ST A TUS, and MESSAGE phases are grouped together as information tr ansfer phases because they are all used to transfer dat a or control information via the data bus. The actual content s of the infor mation is beyo nd the scop e of this sectio n.[...]

Parallel SCSI Interface Product Manual, Rev. A 61 Synchronous transfers shall only be used for negotiated tran sfer rates less th an or equal to Fast-80. Paced transfers shall only be use d for a negotiated tr ansfer rate of Fast- 160. 3.5.1 Asynchronous transfer The targ et shall control the direction of information transfer by means of the I/O si[...]

62 Parallel SCSI Interface Product Manual, Rev. A hold time afte r the assertion of the REQ signal. The target shall assert the REQ signal for a minimum of one transmit assertion period. Th e targe t may then negat e the REQ signal and change or release th e DB(7- 0,P_CRCA) or DB(15-0,P_CRCA,P1) signals. The init iator shall read the value on the D[...]

Parallel SCSI Interface Product Manual, Rev. A 63 3. shall delay at least one transmit setup time; 4. shall transition the ACK sign al; 5. shall hold the DB(15-0) signals valid for a t least one transmit hold time; 6. shall not change the ACK sign al for a mini mum of one tran smit assertion period; and 7. may then change or release the DB(15-0) si[...]

64 Parallel SCSI Interface Product Manual, Rev. A ABORT T ASK message (see Section 4.5.2 ) to the t arget. The target shall send a SPI L_Q/SPI sta tus informa - tion unit pair to the initiator wi th a CHECK CONDITION status and a sense key set to Ab orted Command for the task associated with th e received ABORT T ASK message. 3.5.2.2.1.2 DT DA T A [...]

Parallel SCSI Interface Product Manual, Rev. A 65 2. read the valu e of the P_CRCA signal within on e p CRC receive hold time of the transition of the REQ signal; and 3. respond with an ACK tra nsition. If the I/O signal is false (i.e., tr ansfer to the t arget), to transfe r the data field, the initiator: 1. shall wait until af ter detecting a REQ[...]

66 Parallel SCSI Interface Product Manual, Rev. A Note. The above requirement s in steps 6), 10), and 14) to not wait for the ACK transition correspondin g to the previous REQ tr ansition were not present in th e SPI-3 st andard. For compatibi lity with old designs SCSI initiator port s should generate ACK tr ansitions for all received REQ trans it[...]

Parallel SCSI Interface Product Manual, Rev. A 67 Pad field dat a and pCRC field dat a are tran sferred using the same negotiated transfer peri od as the dat a field data. The target may continue to send REQs, up to the negotiated offset, fo r the next data group. The target shall not transition REQ with P_CRCA asserted un til the initiator has res[...]

68 Parallel SCSI Interface Product Manual, Rev. A The tar get shall read the value of th e DB(15-0) signals within one re ceive hold time of the transition of the ACK signal. The initiator shall use the pad bytes, if any , in the generation of the transmit ted pCRC. The target shall then use those pad byte s, if any , for checking agains t th e com[...]

Parallel SCSI Interface Product Manual, Rev. A 69 If the ret ain training infor mation is enabled, a trainin g pa ttern shall be transferre d at the start of the first DT DA T A phase for each dat a transfer direction af ter the retain training infor mation is enabled. The SCSI device shall save tr aining configur ation values for each I_T nexus th[...]

70 Parallel SCSI Interface Product Manual, Rev. A 4. simultaneously assert and negate P1, P_CRCA, and DB (15-0) signals at twice the negotiated transfer period (i.e., simult aneously repeat a 1 100b bit patt ern 12 times on each signal) while asserting and negating REQ at the negotiated transfer per iod 24 time s [e.g., (2 x 6.25 ns) x 24 = 300 ns [...]

Parallel SCSI Interface Product Manual, Rev. A 71 The SCSI initiator port shall b egin the section A of its training p attern independent of th e start of the SCSI ta r - get ports training pattern if it det ects the SEL and MSG true, and C/D and I/O false on the first assert ion of the REQ signal. The SCSI initiator port shall transmit the followi[...]

72 Parallel SCSI Interface Product Manual, Rev. A The data inva lid state shall have at least one tran sition of P1 before changing states. The minimum dat a invalid time is four transfer periods. This ensures a maximum r un length of three cycles for P1. The dat a invalid state shall last an even number of transfer periods. From the dat a invalid [...]

Parallel SCSI Interface Product Manual, Rev. A 73 The SCSI target po rt shall begin p acing tr ansfers only after meeting all the follo wing: • signal restric tions betw een informatio n transfer p hases listed in Section 3.10 ; • the signal restrictions between a RESELECTION phase and a DT DA T A IN phase listed in Section 3.3.2 ; or • the s[...]

74 Parallel SCSI Interface Product Manual, Rev. A and (e) shall hold the DB(15- 0) signals valid for a minimum o f one transmit hold time. If the I/O signal is false (i.e., transf er to the SCSI targ et por t), to receive SPI information un its the SCSI target port: (a) shall read the value of the DB(15-0 signals within one rece ive hold time of th[...]

Parallel SCSI Interface Product Manual, Rev. A 75 T able 22: Wide SCSI byte order If the last information byte transferred does not fall on the DB(15-8) signals for a 16-bit wide tr ansfer , then the values of the remaining highe r-numbered bit s are un defined . However , wh en using parity prot ection, the DB(P1) signal for this undef ined byte s[...]

76 Parallel SCSI Interface Product Manual, Rev. A 3.7.3 DT DA T A OUT phase The DT DA T A OUT phase allows the SCSI t arget port to request that data b e sent from th e SCSI initiator device to the SCSI target device usin g DT data transfe rs. The target shall assert the MSG signa l and negate the C/D and I/O signals du ring the REQ/ACK handshakes [...]

Parallel SCSI Interface Product Manual, Rev. A 77 A QAS-capable SCSI initi ator port shall assert ACK for a minimum of one QAS non-data phase REQ(ACK) period. 3.9.2.1 MESSAGE IN phase exce ption condition h a ndling If the SCSI initiator port detects a p ari ty error on any message byte it receiv es, the SCSI initia tor port shall cre - ate an atte[...]

78 Parallel SCSI Interface Product Manual, Rev. A d. When switching the Data Bus or DB(P_CRCA) signal dire ction from out (SCSI initia tor port driving) to in (SCSI target port driving), the targ et shall delay driving the Data Bus, DB(P_CRCA), and/or DB(P1) by at least one dat a release delay plus one bus settle dela y after asserting the I/O sign[...]

Parallel SCSI Interface Product Manual, Rev. A 79 The final information trans fer phase is normally the MESSAGE IN phase wher e a DISCONNECT or T ASK COMPLETE message is transferred, followed by the BUS FREE phase. Figure 1 1. Phase sequences for p hysical reconnection an d selection usin g attention cond ition with information unit transfers disab[...]

80 Parallel SCSI Interface Product Manual, Rev. A 3.1 1.4 Phase sequences for physical r econnection or select ion without us ing attention condition with info rmation unit tran sfers ena bled The sequences for p hysical reconnection or selection without using a t tention condit ion while an information unit transfer agreement is in effect shall be[...]

Parallel SCSI Interface Product Manual, Rev. A 81 3.1 1.5 Phase sequences for physical selection us ing attention condit ion with information unit transfers enabled The sequences for a selection with attention cond ition while an information unit transfer agreement is in effect shall be as shown in Figure 14 . The normal progressi on for selection [...]

82 Parallel SCSI Interface Product Manual, Rev. A For COMMAND, MESSAGE, and ST A TUS phases, the DB(P_C RCA) signal shall indicate odd parity fo r DB(7- 0). The DB(P1) signal shall not be checked. For ST DA T A phases, the DB(P_CRCA) signal shall indicate odd p arity for DB(7-0). If 8-bit transfers are enabled, the DB(P1) signal shall not be checke[...]

Parallel SCSI Interface Product Manual, Rev. A 83 4.0 Message system specification SCSI protocol messages a llow communication between a SCSI initiator port and a SCSI targe t port for the pur - pose of link management. The link managem ent messages us ed for this purpose are defined within this stan - dard and their use is confined to this standar[...]

84 Parallel SCSI Interface Product Manual, Rev. A T able 24: Message format 4.2.1 One-byte messages One-byte messages consist of a single byte transferred duri ng a MESSAGE phase. The byte’s message code determines the message t o be perfor med as defin ed in T ables 27 , 40 , and 45 . The IDENTIFY message is a one-byte code, but it s format is d[...]

Parallel SCSI Interface Product Manual, Rev. A 85 T able 26: Extended Message Code s 1. The EXTENDED MESSAGE ARGUMENTS are specifie d within the Extended Message Descriptions in Paragraphs re ferenced in T able 27 . 4.3 Message categories The messages supported by the vario us drives are divided up into categorie s and listed in t ables in the foll[...]

86 Parallel SCSI Interface Product Manual, Rev. A Key: M = Mandatory support O = Optional support NS = Not supported IN = SCSI target port to SCSI initiator port O UT = SCSI Initiator port to SCSI target port Y es = SCSI Initiat or port shall cle ar the attentio n condition be fore last ACK of the Messag e Out phase. Not required = SCSI Initiator p[...]

Parallel SCSI Interface Product Manual, Rev. A 87 4.3.2 DISCON NECT The DISCONNECT message is sent from a SCSI t arget port to inform an initiator that the t arget plans to do a physical disconnect by releasing the BSY signal, and that a later physical reconnect is going to be required in order to complete the current task. This message shall not c[...]

88 Parallel SCSI Interface Product Manual, Rev. A Only one logical unit number shall be identified per t a sk. The initiator may send one or more IDENTIFY mes - sages during a task. A sec ond IDENTIFY me ssage with a different value in t he LUN field shall n ot be issued before a BUS FREE phase; if a tar get receives a second IDENTIFY message with [...]

Parallel SCSI Interface Product Manual, Rev. A 89 4.3.5 INITIA TOR DETECTED ERROR The INITIA TOR DETECTED ERROR message is sent from an initiator to inform a ta rget that an error h as occurred that does not preclude the t arget from retrying the task. The source of the error may either be related to previous activities on the SCSI bus or may be in[...]

90 Parallel SCSI Interface Product Manual, Rev. A It is recommended that th e targe t not attempt to move the data pointer o utside the range addressed b y the command. Initiators may or may not place further restrict ions on the accep table values. Should t he target send an Argument value that is not supported by the initiator , the in itiator ma[...]

Parallel SCSI Interface Product Manual, Rev. A 91 T able 32: MODIFY BIDIRECTIONAL DA T A POINTER message format 4.3.1 1 NO OPERA T ION The NO OPERA TION message is sent fr om an initiator in response to a t arget’ s request for a message when the initiator does not currently have any other valid message to send. For example, if the t arget does n[...]

92 Parallel SCSI Interface Product Manual, Rev. A 4.3.12 P ARALLEL PROTOCOL REQ UEST P ARALLEL PROTOCOL REQUEST messages (see T able 33 ) are used to negotiate a synchronou s data trans - fer agreement, a wide da ta tran sfer agreement, and se t the protocol options betwe en two SCSI devices. T able 33: P ARALLEL PROTOCOL REQUEST message format [1][...]

Parallel SCSI Interface Product Manual, Rev. A 93 See Section 3.5 for an explanation of the di fferen ces between ST and DT data transfers. The REQ/ACK OFFSET value is chosen to pre vent overflow conditions in th e port’ s receive buf fer and offset counter . The REQ/ACK OFFSET values and which ti ming values shall be selecte d are define d below[...]

94 Parallel SCSI Interface Product Manual, Rev. A T able 34: V alid protocol options bit combinations A Parallel Protocol Request agreement applies to all logical units of the two SCSI d evices that negotiated agreement. That is, if SCSI device A, acting as an in itiator , negotiates a dat a transfer agreement with SCSI device B (a t arget), then t[...]

Parallel SCSI Interface Product Manual, Rev. A 95 be changed. Each SCSI device when transmitting data shall respect the negotiated limits se t by the other's P ARALLEL PROTOCOL REQUEST messa ge, but it is permit ted to transfer dat a with larger periods, smaller synchronous REQ/ACK of fsets, or both. The completion of an exchang e of P ARALLEL[...]

96 Parallel SCSI Interface Product Manual, Rev. A If an abnormal condition p revents th e target from respond ing with a P ARALLEL PROTOCOL REQUEST mes - sage or with a MESSAGE REJECT message, then both SCSI devices shall use the eight-bit/asynchr onous data transfer mode with all the protocol option s bits set zero to indicate ST DA T A IN and ST [...]

Parallel SCSI Interface Product Manual, Rev. A 97 4.3.16 SYNCHRONOUS DA T A TRANSFER REQUEST Synchronous Data Transfer Req uest (SDTR) messages (see T a ble 36 ) are used to negotiate a synchronous data transfer a greement between two SCSI devices. T able 36: Synchronous Dat a T ransfer Request message format The TRANSFER PERIOD F ACT OR field valu[...]

98 Parallel SCSI Interface Product Manual, Rev. A a. after a HARD RESET ; b. after a T ARGET RESET message; c. after a power cycle; and d. af ter a change in the transceiver mode (e.g., L VD mode to MSE mode). Any condition that leaves the dat a tr ansfer a greement in an inde terminate st ate shall cause the SCSI device to enter an asynchronous d [...]

Parallel SCSI Interface Product Manual, Rev. A 99 4.3.16.1 T arget initia ted SDTR negotiation If the ta rget recognizes tha t SDTR negotiation is req u ired, it send s an SDTR message to the initiator . The initi - ator shall crea te an attention condition on the la st byte of the SDTR message fr om the t arget, and the initiator shall respond wit[...]

100 Parallel SCSI Interface Product Manual, Rev. A 4.3.18 WIDE DA T A TRANSFER REQU EST WIDE DA T A TRANSFER REQUEST (WDTR) m essages (s ee T able 38 ) are used to negotiate a wide dat a transfer agreement between two SCSI devices. T able 38: WIDE DA T A TRANSFER REQUEST message format The TRANSFER WIDTH EXPONENT field defines the transf er width t[...]

Parallel SCSI Interface Product Manual, Rev. A 101 fer agreeme nt sha ll remain intact; b. If a WDTR message fails for any o t her reason, the prior synchronous data transfer agreement shall remain intact; or c. If a WDTR message is not rejected with a MESSAG E REJECT message, a WD TR message shall reset the synchronous dat a transfer agreement to [...]

102 Parallel SCSI Interface Product Manual, Rev. A get causing an unexpe cted bus free. The in itiator shall a ccept such action as abortin g the WDTR negotiat ion, and both SCSI de vices shall go to e ight-bit data tr ansfer mode for data tra nsfers between the two SCSI devices. Any prior synchron ous data transfer agreem ent shall remain intact. [...]

Parallel SCSI Interface Product Manual, Rev. A 103 When a tar get does a physical re connection to an initiator to continue a t agged task, the Simple Queue mes - sage shall be sent following the Identify message to resum e the I_T_L_Q nexus for the task. Only one I_T_L_Q nexus may occur during a physical reconnection. If the Simple T ag mes sage i[...]

104 Parallel SCSI Interface Product Manual, Rev. A 4.4.3 HEAD OF QUEUE See T able 42 for the format of the Head of Queue message. T able 42: Head of Queue message f o rmat The Head of Queue message specifies that th e task shall be placed in the task set as a Head of Queue t ask. The rules us ed by the device serve r to handle He ad of Queue tasks [...]

Parallel SCSI Interface Product Manual, Rev. A 105 4.5 T ask management messages Ta b l e 45 lists the codes used for me ssages that manage t asks. Details about these t ask management mes - sages is given in subsect ions following the table. 4.5.1 T ask managemen t message codes T able 45: T ask management message code s Key: M = Mandatory support[...]

106 Parallel SCSI Interface Product Manual, Rev. A 4.5.3 ABORT T ASK SET The ABORT T ASK SET message is define d in the SCSI Architec ture Model-4 st andard. In addition to the requirement s in the SCSI Architecture Model- 4 standar d the targ et shall go to the BUS FREE ph ase following the successful rece ipt of the ABORT T ASK SET message. If on[...]

Parallel SCSI Interface Product Manual, Rev. A 107 5.0 Miscellaneous SCSI bus characteristics Asynchronous conditions can o c cur on the SCSI bu s that ca use a SCSI device to pe rform certain actions that may alter the phase sequen ce of an I/O process. Furthe rmore, SCSI d evices may not all be powered on at the same time. This publication does n[...]

108 Parallel SCSI Interface Product Manual, Rev. A A SCSI target port sh all respond to an atte ntion condition with MESSAGE OUT phase as follows: a. If an attention condition is cr eated during a COMMAND phase, t he target shall enter MESSAGE OUT phase af ter transferr ing par t or all of the command descr iptor block. b. If an attention condition[...]

Parallel SCSI Interface Product Manual, Rev. A 109 The effect of the hard reset on tasks that have not completed, SCSI device reservations, and SCSI device operating modes is defined in the SCSI Archite cture Model-4 stand ard. Any SCSI device that dete cts a ha rd reset shall also set it s transfer agre ement to the default transfer a gree - ment.[...]

110 Parallel SCSI Interface Product Manual, Rev. A • Active po inters (one set per initiator only). • Saved pointers (one or more set s per initiator , up to fifteen set s total). The use of these two types of pointer s is described in the following paragr aphs. 5.5.2 Active pointers Active pointers represent the curr ent state of th e interfac[...]

Parallel SCSI Interface Product Manual, Rev. A 111 5.6 Command processing considerations and e xception conditions 5.6.1 Command processing consid erations and exc eption conditions overview The following subclauses descr ibe some aspects of co mmand processing, including exception cond itions and error han dling that are specific to this s tandard[...]

112 Parallel SCSI Interface Product Manual, Rev. A A task manager that detect s an incorrect initiator connec tion shall abort all tasks for the initiator and the associ - ated logical unit and shall return CHECK CONDITION status for the task th at caused the incorrect initiator con - nection. The s ense key shall be set to Aborted Comma nd and the[...]

Parallel SCSI Interface Product Manual, Rev. A 113 6.0 SPI information unit s An information unit tran sfer transfers dat a in SPI informa tion units. The order in wh ich SPI information units are transferre d within an information un it transfer fo llows a prescribed sequence. When information unit transfe rs are enabled, only SPI information unit[...]

114 Parallel S CSI Interface Product Manual, Rev. A Logical recon nections occu r on the su ccessful target transmission and init iator receipt of a SPI L_Q informa - tion unit for an existing I/O process. The logical recon nection reest ablishes the I_T_L_Q nexus for that I/O pro - cess. SCSI devices using information unit transfers may receive se[...]

Parallel SCSI Interface Product Manual, Rev. A 115 [1] See T able 49 for the format of the SPI L_Q information unit. [2] See T able 46 for the format of the SPI Command info rmation unit. [3] See Figure 16 . [4] See Figure 18 . Figure 15. SPI information unit sequence durin g initial connecti on SPI L_Q (alwa ys Init to T arg) (logical connect) DT [...]

116 Parallel S CSI Interface Product Manual, Rev. A [1] See T able 49 for the format of the SPI L_Q i n formation unit. [2] See T able 52 for the format of the SPI Dat a information unit. [3] See Figure 18 . Figure 16. SPI information unit sequence durin g data type transfers SPI L_Q (alwa ys T arg to Init) (logical reconnect) DT D A T A IN (from S[...]

Parallel SCSI Interface Product Manual, Rev. A 117 [1] See T able 49 for the format of the SPI L_Q information unit. [2] See T able 53 for the format of the SPI Dat a information unit. [3] See Figure 18 . Figure 17. SPI info rmation unit sequence during data stream type transfer s SPI L_Q (alwa ys T arg to Init) (logical reconnect) DT D A T A IN (f[...]

118 Parallel S CSI Interface Product Manual, Rev. A [1] See T able 49 for the format of the SPI L_Q i n formation unit. [2] See T able 54 for the format of the SPI S tatus information unit. [3] See Figure 16 . Figure 18. SPI information unit sequence during status transfers 6.2 SPI information unit s 6.2.1 SPI command information unit The SPI comma[...]

Parallel SCSI Interface Product Manual, Rev. A 119 If the T ask Management Flags field is a supporte d value not equal to 00h , the t arget shall perfo rm the selected task mana gement function before processing any fur t her SPI information unit s regardless of the command type. On completion of a su pport task man agement function, the ta rg et s[...]

120 Parallel S CSI Interface Product Manual, Rev. A T a ble 47: T ask Attribute [2] The T ask Management Flags field is define d in T able 48 . If a T ask Management function fails, the T ask Manager shall te rminate the t ask wit h Good status. The p acketized failure code shall be set to T ask Man - agement Function Failed. T a ble 48: T ask Mana[...]

Parallel SCSI Interface Product Manual, Rev. A 121 Management Flags field is not zero. Any bytes between the end of a 6 byte CDB, 10 byte CDB, or 12 byte CDB and the end of the CDB field shall be reserved. [6] The Additiona l CDB field contains any CDB bytes beyo nd those cont ained within the standard 16 byte CDB field. [7] The CDB, Additional CDB[...]

122 Parallel S CSI Interface Product Manual, Rev. A [1] The T ype field is defined in T able 50 . If a SCSI initiator port receives a type code that is not defin ed in Ta b l e 50 , that initiator shall follow the procedures defined in Section 3.5.2.2.1.1 . If a SCSI target port receives a type code that is not defined in T able 50 , that target sh[...]

Parallel SCSI Interface Product Manual, Rev. A 123 T a ble 50: SPI L_ Q in formation unit type [2] T ag field is a 16-bit un signed integer assign ed by the ap plication client and sent to the initiator in the Send SCSI Command requ est. See Section 4.4.1 , T ask attribute message overview and codes. [3] The Logical Unit Number field specifies the [...]

124 Parallel S CSI Interface Product Manual, Rev. A than 509 would transfer 509 bytes of dat a plus 3 bytes of pad plus 4 bytes of iuCRC for a total tran sfer of 516 bytes). The t a rget shall not set the dat a length to a value that exceeds the maximum burst size as defined in the disconnect-re connect page (see Seagate SCSI Command Refer ence Man[...]

Parallel SCSI Interface Product Manual, Rev. A 125 6.2.3 SPI dat a information unit The SPI data infor mation unit (see T able 52 ) contains dat a. The detection of a BUS FREE pha se following a SPI dat a information unit by a SCSI initiator port shall be equivalent to the initiator re ceiving a D ISCONNECT message. The detection of a QAS REQUEST m[...]

126 Parallel S CSI Interface Product Manual, Rev. A tion unit the P_CRCA signal was asserted and a SCSI init iator port detect s a REQ transition after re ceiving the last iuCRC for a SPI data stream info rmation unit, that SCSI in itiator shall logically disconnect from the current I_T_L_Q nexus. If, during a sequence o f SPI data str eam informat[...]

Parallel SCSI Interface Product Manual, Rev. A 127 6.2.5 SPI status information un it The SPI st atus information unit (see T able 54 ) contain s the completion status of the t ask indicated by the pre - ceding SPI L_Q info rmation unit. The t a rget shall consider the SPI status information unit t ransmission to be successful when there is no atte[...]

128 Parallel S CSI Interface Product Manual, Rev. A Data List Length field and shall assume a length of zero. [4] If packetized failure data is p rovided, the Packetiz ed Failures V alid (RSPV ALID) bit shall be set to one and the Packetized Failures List Length fi eld shall specify the number of byte s in the Packetized Failures field. The Packeti[...]

Parallel SCSI Interface Product Manual, Rev. A 129 The iuCRC field shall use the algorith m define d in Subsection 1 1.3, ANSI SCSI Parallel Interface (SPI-5), T10/ 1525D.[...]

130 Parallel S CSI Interface Product Manual, Rev. A[...]

Parallel SCSI Interface Product Manual, Rev. A 131 7.0 SCSI commands This section defines the SCSI comm and structure and describes a typical SCSI bus proce dure involving a command, status retu rn, and message interchange. The command structure defined herein provides for a contiguous set of logical blocks of data to be transferred across the in t[...]

132 Parallel SCSI Interface Product Manual, Rev. A The Command Descriptor Block alw ays has an operat ion co de as the first byte of the command. This is fol - lowed by command p arameters (i f any), and a control field. For all commands, if ther e is an in valid p arameter in the Command Descripto r Block, the drive shall terminate the command wit[...]

Parallel SCSI Interface Product Manual, Rev. A 133 7.2.1 Fixed and variable length Command Descript or Block format s For all commands, if the re is an invalid p arameter in the command descripto r block, the device server termi - nates the command without altering the medium. Ta b l e 57 shows the typical format of a 6-byte CDB. T able 58 sh ows a[...]

134 Parallel SCSI Interface Product Manual, Rev. A T a ble 59: T ypical CDB fo r 12-byte commands See notes following T able 61 . T a ble 60: T ypical CDB fo r 16-byte commands Bit Byte 76543210 0 OPERA TION CODE [1] 1 Reserved SERVICE ACTION (if required) [2] 2 (MSB) LOGICAL BLOCK ADDRESS (if required) [3] 3 4 5 (LSB) 6 (MSB) TRANSFER LENG TH (If [...]

Parallel SCSI Interface Product Manual, Rev. A 135 See notes following T able 61 . T a ble 61: T ypical variable length CDB Notes for T ables 57 , 58 , 59 , 60 , and 61 . [1] The Operation Code field of the Command Descripto r Block cont ains the code value indentifying the oper - ation being requ ested by the CDB. The Operation Cod e provides for [...]

136 Parallel SCSI Interface Product Manual, Rev. A 8.0 where the details of eac h command are describe d. [3] The Logical Block Address on logical units or within a p artition on device volumes shall begin with block zero and be contiguous up to the last logical blo ck on that logical un it or within that partition. A six-byte command descriptor bl[...]

Parallel SCSI Interface Product Manual, Rev. A 137 T a ble 62: Co ntrol field [a] The Normal Auto Contingent Allegi ance (NACA) bit is used to control the rules for handling a n Auto Contingent Allegiance (ACA) conditio n caused by the comma nd. Section 7.6.1.1 specifies the actions to be ta ken by the logical unit in response to an ACA condition f[...]

138 Parallel SCSI Interface Product Manual, Rev. A 7.3 St atus A S tatus byte shall be sent from the t arget to the init iator during the ST A TUS phase at the termination of each command as specified in T ables 63 and 64 unless the command is cleared by one of the following co nditions: 1. an Abort m essage 2. a Bus Device Rese t message 3. a hard[...]

Parallel SCSI Interface Product Manual, Rev. A 139 Busy . This status indi cates that the logical unit is busy . This status shall be return ed whenever a logical u nit is unable to accept a comma nd from an otherwise accept abl e initiator (i.e., no reservat ion conflicts). Th e recom - mended initiator reco very action is to i ssue the command ag[...]

140 Parallel SCSI Interface Product Manual, Rev. A 7.4 Command examples 7.4.1 Single command example A typical operation o n the SCSI bus i s likely to include a sin gle READ command to a peripheral device such as the drive. This oper ation is described in detail st arting with a request from the initiator . This example assumes that no linked comm[...]

Parallel SCSI Interface Product Manual, Rev. A 141 7.4.2 Disco nnect example In the single command example, the le ngth of time necessary to obt ain the data may require a time consuming physical seek. In orde r to improve system thr o ughput, t he drive may disconnect from the initiator , freeing the SCSI bus to allow other requests to be sent to [...]

142 Parallel SCSI Interface Product Manual, Rev. A 7.5 Timing e xamples T imes (T00 through T35) necessary to define performance ar e listed in the in dividual drive’ s Product Manual, in the “Disc drive SCSI timing” section. F or timing wavefo rms to define these times, refer to the SCSI Pa rallel Interface-5 specification (SPI-5 ). 7.6 Comm[...]

Parallel SCSI Interface Product Manual, Rev. A 143 The handling of t a sks created by initiators other than t he faulted initiator depends on the va lue in the TST field in the Control mode page (see ANSI SCSI Primar y Commands-4, T1 0/1731-D). If TST=000b, tasks created by other initiators while th e AC A or CA condition is in ef fect shall not be[...]

144 Parallel SCSI Interface Product Manual, Rev. A Note. Some logical unit s may not detect an overl apped command until af ter the command descriptor block has been received . 7.6.3 Incorrect lo gical unit selection The target’ s response to an incorrect logical unit identifier is described in the following p a ragraphs. The logical un it identi[...]

Parallel SCSI Interface Product Manual, Rev. A 145 The control mode p a ge cont ains para meters affecting th e use of asynchronous event r eporting (see Seagate SCSI Command Refere nce Manual, Part numbe r 100293068) . Asynchronous Eve nt Reporting is used to signal a device that one of th e four events listed below has oc curred: a. an error co n[...]

146 Parallel SCSI Interface Product Manual, Rev. A 7.6.6 Unit Attention condition The drive sets up the Unit Attention co ndition when it stores ( within itself) a Unit Attention condition flag for each device on th e SCSI bus having a SCSI initiato r port relationship with the drive, and this Unit Attention condition persists for each in itiator u[...]

Parallel SCSI Interface Product Manual, Rev. A 147 7.6.7 T arge t hard reset a SCSI target port hard r e set is a SCSI target port re sponse to a SCSI target port Reset t ask management request (see SCSI Architecture Model-4, T1 0/1 157D), or a reset event within the service delivery subsystem. The definition of t arget reset events is pr otocol an[...]

148 Parallel SCSI Interface Product Manual, Rev. A The I T L nexus specifies th e relationship so that the drive can a lways reconnect to the initiator to restore the pointers for t ask as long as only one command per I T L nexus is issued. It is the res pons ibility of t he initiator to assure that only one command is issued at any time. 7.7.2 T a[...]

Parallel SCSI Interface Product Manual, Rev. A 149 The drive recove ry option, is to cont inue execution of commands in the q ueu e after the contingent allegiance condition has cleared. The drive retur ns Busy status to all other initiators while the continge nt allegiance condi - tion exists. Duri ng this time all commands in the que ue are suspe[...]

150 Parallel SCSI Interface Product Manual, Rev. A Since new operating definitions may pr eclude the execution of tasks that ar e already in prog ress, the target may disconnect to allo w completion of any tasks tha t ar e in progress. Ope rating definition changes that may cause conflicts with the normal operation from other initiators sha ll be i[...]

Parallel SCSI Interface Product Manual, Rev. A 151 8.0 Drive features 8.1 S.M.A.R.T . system Some drive families me ntioned in Section 1.1 implement what is called in the industry the S.M.A.R.T . system. S.M.A.R.T . is an acronym for Self-Monitoring Analysis a nd Reporting T echnology . The intent of the S.M.A.R.T . system is to recognize condition[...]

152 Parallel SCSI Interface Product Manual, Rev. A The test s performed in the segme nts may be the same for the short and extended self-test s. The time required by a logical unit to complete it s extended self-test is re ported in the Extended Self-T est Completion T ime field in the Control mode page (see Seagate SCSI Command Reference Manual, P[...]

Parallel SCSI Interface Product Manual, Rev. A 153 T able 65: Exception commands f or background self- test s a. Device types not listed in this t able do not have commands that are excep tions for background self- tests, other than th ose listed above for all device types. b. See Sea gate SCSI Command Reference Ma nual, Part number 100293 068. If [...]

154 Parallel SCSI Interface Product Manual, Rev. A T able 66: Self-test mode summary 8.3 Alternate error detection for the asynchronous information p hases (AIP)— Command, Message, and S tatus 8.3.1 Error detection for asynchronous information pha ses This section describes an en hanced error d etection me thod for the Command, Message, and S tat[...]

Parallel SCSI Interface Product Manual, Rev. A 155 8.3.2.1 Covere d signals Ta b l e 67 defines the signals to be co vered by th e protection code and th eir bit location s in the 21-bit code word. When a SCSI device receives an information byte , it also la tches the st ate of the othe r SCSI signals and values noted in T able 67 . T able 67: Sign[...]

156 Parallel SCSI Interface Product Manual, Rev. A For each new run, the Sequence ID is set to zero for the first word transferred , set to on e for the second wor d transferred, set to two for the third word transferred, and set to thr ee for the fourth word transferred. The Sequence ID then cycles back to bein g set to zero for the fif th word tr[...]

Parallel SCSI Interface Product Manual, Rev. A 157 8.3.2.2 Code des cription The protection code (see T able 68 ) is a cyclic bi nary BCH code . T able 68: Protection code The BCH protection code is a cyclic code with a generator polynomial of x 6 + x 5 + x 2 + 1. The canonical fo rm of the code genera tor is shown in Figure 21 . This is a serial i[...]

158 Parallel SCSI Interface Product Manual, Rev. A 8.3.3.1 Protectio n code transmi ssion SCSI devices supporting this protec tion code transmit t he protection code check data during all Command, Message, and ST A TUS phases. The protection code byte is transferred on the upp er eight bits of a wide bus simultane ously with the info rmation day by[...]

Parallel SCSI Interface Product Manual, Rev. A 159 8.4.2 Case 1—Power off during removal or insertion a. All SCSI devices are powered of f during physical reconfiguration. 8.4.3 Case 2—RST signal asserted continuously during removal or insert ion a. RST signal sh all be asserted continuously by the initiator during removal or insertion. b. The [...]

160 Parallel SCSI Interface Product Manual, Rev. A c. A SCSI device being removed sh all maintain its power gr ound and logic grou nd prior to, during, and for at least 1 ms after the disconne ction of any device connector cont act from the SCSI bus. d. The SCSI device being removed or inserted shall employ transceivers that conform to the applicab[...]

Parallel SCSI Interface Product Manual, Rev. A 161 Index A abort message 138 abort task 138 abort task message 105 abort task set message 106 aborted command 4, 143 , 15 0 ACA. see Auto Continge nt Allegiance ACK. see Acknowledge acknowle dge SCSI bus signal 15 active pointer 110 , 140 adapter host 14 Additional CDB SPI command information unit 119[...]

162 Parallel SCSI Interface Product Manual, Rev. A code value reserved 131 command 4, 6 aborted 4 completed 5 ended 6 linked 7 overlapped 143 SCSI-3 standards 2 single, example 140 third party 11 unlinked 11 untagged 149 command complete message 140 , 141 command completio n 131 command data 5 command data signal 29 Command Descriptor Block SPI com[...]

Parallel SCSI Interface Product Manual, Rev. A 163 disconnect privile ge 148 domain 5, 9 dormant task state 5 double transition 6 DP-1 signals 34 drive select 17 driver 6 driver precom pensation 36 DT Data In 5 DT Data In phase 5, 38 DT Data Out 5 DT Data Out phase 38 DT Data phase 7, 38 DT DATA phases 37 DT Data phases 31 , 34 DT timing values 23 [...]

164 Parallel SCSI Interface Product Manual, Rev. A information unit seq uence 113 information unit transfer 6, 38 initial connection 6 initiator 3, 6, 14 , 131 , 140 faulted 6 multiple 3, 14 single 14 initiator connection incorrect 150 initiator dete cted error message 89 initiator port 13 input/outpu t SCSI bus signal 15 input/output. see also I/O[...]

Parallel SCSI Interface Product Manual, Rev. A 165 multidrop 7 multimode SCSI bus signal 15 multimode I/O circuits 15 multimode single-ended 7 multiple initiator 14 multiple initiators 3 multiple target 14 N NACA. see Normal Auto Contingent Allegiance negated edge 6 negotiate 40 negotiation 40 negotiation me ssage sequences 49 nexus 6 , 8 no operat[...]

166 Parallel SCSI Interface Product Manual, Rev. A protection code er ror 158 protection code ge nerator 157 protection cod e transmission 158 protocol 8 layer 9 lower level 7 option 8 SCSI 9 SCSI-3 standards 2 service confir mation 8 service indication 8 service reque st 9 service response 9 service, unconfirmed 11 upper level 11 protocol optio n [...]

Parallel SCSI Interface Product Manual, Rev. A 167 RSPVALID. see Packe tized Failures Valid RST. see Reset S save data pointer message 96 , 141 saved pointer 110 SCSI standards, scope of 2 SCSI application layer 9 protocol transaction 9 SCSI architecture model SCSI-3 standards 2 SCSI bus 13 , 140 , 141 procedure 131 signals 15 timing 20 SCSI bus ch[...]

168 Parallel SCSI Interface Product Manual, Rev. A SPI status information unit 113, 127 ST Data phase parallel tran sfers 38 ST DATA phas es 37 ST LVD phases 34 state of the bus 6 Status SPI status information unit 127 , 128 status 6 , 138 status byte 131 , 13 8 status phase 138 status prec edence 139 status response 5 stored pointer 140 subsystem [...]

Parallel SCSI Interface Product Manual, Rev. A 169 two-byte message 84 Type SPI L_Q information un it 121 , 122 U Ultra160 1 Ultra320 1 unconfirme d protocol service 11 unexpected bus free 138 unit attention condition 146 , 150 unit attention mode parameters page 146 unit attention parameter s 146 unit attention sense key 146 unlinked com mand 11 u[...]

170 Parallel SCSI Interface Product Manual, Rev. A[...]

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