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Содержание TDC 3620

Страница 1: ... l TANDBERG DATA TDC 3600 SERIES STREAMING TAPE CARTRIDGE DRIVES r Toe 3620 3640 3660 Reference Manual ...

Страница 2: ...rature Variation 3 3 Atmospheric Pressure 3 3 Vibration 3 3 Impact and Shock 3 3 Product Performance Specifications 3 4 Audible Noise 3 4 Radiated Electromagnetic Interference 3 4 Susceptibility to Electromagnetic Interference 3 4 Static Discharge 3 4 Safety Standard 3 4 Mean Time to Repair 3 4 Product Reliability 3 5 Electronics MTBF 3 5 Mechanics MTTF 3 5 Useful life Cycle 3 5 Functional Specifi...

Страница 3: ...l Functions 7 1 7 1 Reference Track 7 1 7 1 1 Write Reference Track 7 1 7 1 2 Read Reference Track 7 2 7 2 Write Data and Filemarks 7 3 7 2 1 Write From Beginning of Tape 7 3 7 2 2 Write From a Position on the Tape 7 3 7 2 3 Terminate Write From a Position on the Tape 7 4 7 2 4 Terminate Write at Physical End Of Tape 7 4 7 2 5 Terminate Write at Physical End Of Tape Executing the Copy Command 7 5 ...

Страница 4: ... Drive Command Set 9 3 Copy 18H 9 4 Command and Parameter Blocks 9 5 Copy Operation _ 9 8 Block Sizes 9 10 Error Handling 9 l Command Descriptor Blocks Used as an Initiator 9 15 Erase 19H 9 17 Inquiry 12H 9 18 Load Unload 1BH 9 21 Mode Select 15H 9 22 Mode Sense 1AH 9 27 PrevenvAllow Media Removal 1 EH 9 30 Read 08H 9 31 Read Command Error Conditions 9 32 Read Block Limits OSH 9 33 Read Data Buffe...

Страница 5: ...5 Preventive Maintenance 10 6 Appendix A Extended Error Code Messages A Appendix B General Error Conditions B 1 AppendIx C Application Notes _ _ ____ C C 1 How to Achieve Streaming Mode Operation C C 2 If Streaming Mode can not be Achieved C 2 C 3 How to Optimize SCSI Per10rmance C 4 Appendix 0 Internal Buffer Operation 0 1 D Data Buffer Design Goal 0 1 0 2 Data Buffer Operation 0 2 iv ...

Страница 6: ...3 8re 85 follows The Copy Command supports only copy between Direct Access and a Sequential Access Drive The Mode Select command does NOT suppon the EMULEX Vendor Unique bits DEA Disable Area Ahead AU Auto Load Inhibit SEC Soft Error Count The following Extended Sense Status Bytes have changed position ERClJERCD Moved from byte 08 to byte 14 Number Of Recoverable Enors Moved from bytes 09 and J0 t...

Страница 7: ... doubt always let a cartridge dry out in a normal humidity em ironment 50 65 rei hum at 20 C for at least 3 4 days prior to use The head life time specifications stated by Tandberg Data A S assumes running tapes in an environment with an average reI hum of not more than 50 and a maximum of not more than 65 aU at a temperature of not more than 30 C outside the cartridge Relative humidities up to 80...

Страница 8: ... mc 3620 Drive complies with the SCSI Interface Standard and the QIC 24 Data Interchange Standard The TDC 3640 and the IDC 3660 Drives comply respectively with the QIC 120 or the QIC 150 Data Interchange Standards in addition to the SCSI specifications The IDC 3620 the IDC 3640 and the IDC 3660 reads and writes nine fifteen or eighteen tracks serially running the tape at 90 ips or 72 ips respectiv...

Страница 9: ...tion of the interface to the Drive regarding software and or system It describes the command set and the behavior ofthe Drive in various situations 1 3 Additional Documentation SCSI Small Computer System Interface manual ANSI X3 131 Standard Revision 17B 1986 The QIC 24 and QIC 02 Standards Revision D Part no 402732 Publ no S447 available from our Sales Department The QIC 120 Standard for Data Int...

Страница 10: ...The IDC 3660 records and reads serially on 18 tracks and can store 155 Mbytes on a 183 m 600 foot cartridge Drive Application The Drive is well suited for a variety of applications Winchester back up Archival storage Low cost background mass storage system Data logging Replacing the floppy disk for data interchanges Streaming The mode of operation is streaming i e the Drive is designed to run the ...

Страница 11: ...omprises the 68 HCll microcomputer and two custom made Tandberg Data ASIC circuits one handling the Drive s fonnatting functions and the other handling the buffer and bus interface circuitry All electronics except the opta electronic tape hole sensors the mechanical cartridge in pJace and write protected switches are situated on the Mainboard The exceptions mentioned are located on the Sensorboard...

Страница 12: ...s to each block prior to writing the complete block on the tape The blocks are written without the traditional long interblock gaps The Drive performs read after write checking and blocks with errors are automatically rewritten funher down the tape Read Operation In read mode data is read from the tape and the formatter ASIC strips off the special address and check characters The data bytes are th...

Страница 13: ...te track locations due to the high resolution of the stepping system Track Seeking In Read Mode When reading the Drive will not look for the edge of the tape No write operation is allowed in read mode Instead the microcomputer will look for the long preamble on the fIrst track using the same edge detector circuit as in write mode The Drive will sense the upper and lower edge of the reference track...

Страница 14: ...stem WriIe Read Head The capstan motor is controlled by a software controlled and monitored servo system Pulse modulation of the motor current is used in order to reduce power dissipation in the motor Head Motion System The head is moved up and down with a double screw worm wheel system controlled by a stepper motor The micro computer supplies the pulses to the stepper motor The micro computer is ...

Страница 15: ...it detects each flux transition from the read head and convens it to a digital pulse The circuit is optimized to read weak signals thus improving the total system error rate The Read Clock Generator This circuit generates a clock signal which follows the long tenn variations in the data signal read back from the tape A phase locked loop is used to control the generation The circuit is optimized fo...

Страница 16: ...ands from the Host The Host may read the Drive status by asking for the transfer of special status bytes from the Drive See Chapter 9 for a complete list of available commands During read and write operations the data bytes are transferred via the Host Bus The transfer of each data byte is supervised by the control lines in a handshake operation to minimize timing burden on the host controller For...

Страница 17: ...TANDBERG DATA 2 8 Introduction to the Drive This Page Intentionally Left Blank ...

Страница 18: ...e Section 4 1 for mounting details and mechanical drawings 3 2 Power Requirements Voltage Current 5V 250mA 12 V motor not running 100mA 12 V motor running with tape 1 2A 12 V peak value start up 3 9 A ExcI the bus termination resistor network Nominal value Actual value depends on cartridge friction Assuming cartridge meeting 3M spec for torque and friction Current A 3 7 A t Sleep fundion turned of...

Страница 19: ...acked and power is turned off The unit is packed in original package as when ready for shipment from factory 3 3 1 Temperature and Relative Humidity Temperature OC Rei humidity 5 40 20 80 30 60 10 90 30 60 10 90 In operating mode these figures are limited by the media Due to additional heating coming from internal friction in the canridge the maximum surrounding temperature should not exceed 40 C ...

Страница 20: ...aximum altitude 13 000 m 40000 ft 3 3 4 Vibration EC 68 2 6 Frequency Peak Displacement Acceleration 5 60 5 58 5 12 60 Hz 0 035 mm 10 500 Hz 0 5 G 58 Hz 0 150mm 10 500 Hz 2 0G 12 Hz 3 5 mm 10 500Hz 2 0G 3 3 5 Impact and Shock Lifted 50 mm and allowed to fall on to each of the four bottom edges and corners Horizontal position see section 4 1 lEC 68 2 31 Lifted 1 0 m and allowed to fal1 freely on to...

Страница 21: ... disturbance MIL SID 462 method RS03 14 kHz 1GHz 3 4 4 Static Discharge The Static Discharge is referred to the front door and other pans of the Drive that are accessible from the front when the Drive is mounted in a cabinet The Drive will withstand a discharge of 15 kV from a capacitor of 150 pF via a 150 n resistor without malfunction or loss of data Normal retries are allowed 3 4 5 Safety Stand...

Страница 22: ...0 POH and by 2 two for 500 1 000 POH The predicted mature MTBF for the electronics pan of the TOe 3600 Series Drives is 20 000 POH 3 5 2 Mechanics MTTF The failure rate for these pans is related to how often the Drive is actually used In the case of the most critical components which are the head and the capstan motor the reliability is specified as the Mean Time to Failure MITF based on the POH a...

Страница 23: ...or 10 000 frpi or better for QIC 24 recordings Only tapes cenified for 12500 frpi should be used for QIC 120 150 recordings When you are recording use DC600A or DC600XTD tapes or similar makes with equal mechanical tolerances for the TOC 3640 IS track QIC I20 version For the TOC 3660 18 track QIC I50 version use DC600Xm tape only See also IMPORTANT notice in Chapter O about tape environmen tal tem...

Страница 24: ...rack 5 Trac Trac 7 Track a Track 4 Track 0 Track Track 2 Track TrtlCk Locationslorthe TDC 36201QIC 24 9 track Drive Traclcl octltiDnslor 1MTDC 3640IQIC 120 IS track Drive TID 13 T 5 TID TID 1 TID T k 7 TID TID 17 1 0 TID T TID TrtlCkLocOlions or 1M TDC 366oIQic IS0 18 track Drive L3 L13 L L13 U ...

Страница 25: ...OS1 mm 0 222 to 0042 0 096 to 002 0 1606 to 002 L6 1 98 mm to 107 nvn L6 1 219 rrvn to OS1 mm L6 1 020 mmtO OS1 mm 0 078 to 0042 0 048 to OO2 0 0402 0 002 L7 4 42 mmtO 107 mm L7 4 064 rrvn to 051 mm L7 2 720mmtO OS1 mm 0 174 to 0042 0 160 to 002 0 1071 to 002 L8 0 76 mmtO 107mm L8 0 406 mm to OS1 mm L8 0 340 mm to OS1 mm 0 030 to 0042 0 016 to 002 0 0134 0 002 L9 L9 3 251 rrvn to OS1 mm L9 2 380 m...

Страница 26: ...rite TDC 3660 sections Erase frequency Azimuth ZenIth Type of operation Tape speed standard Tape speed variation Start stop time Start stop distance 3 6 MHz TDC3620 TDC3540 TDC3660 7 minutes of arc According to ECMA ANSJ 7 minutes of arc According to ECMA ANSJ 7 minutes of arc According to ECMAIANSJ 15 minutes of arc 3 6 4 Tape Movement Streaming TDC3620 TDC3540 TDC3660 2 29 m s 90 ips 1 83 m s 72...

Страница 27: ... CRC 2 and Postamble 0 5 IDC 3640 60 23 5 Bytes Preamble 16 Byte Marker I Block Addr 4 CRC 2 and Postamble 0 5 Writing always starts from the beginning of Track 0 except when the Host tells the Drive to start writing from the last block recorded All tracks are erased when writing from BOT on Track O Tracks are written in an evenly rising order i e 0 I 2 etc Reading always starts from the beginning...

Страница 28: ...t tracks Type of capstan motor Servo system capstan tachometer BOTIEOT sensor cartridge sensor Write protect n Or Tolerance on maximum operating head travel 0 03 mm 0 0012 maximum TDC3620 TDC3640 TDC3660 Norrrinally 122 steps Norrrinally 81 steps Norrrinally 68 steps 3 6 8 Capstan System High inenia coreless DC motor Dual feedback system using an optical tachometer Speed vari ations are continuall...

Страница 29: ...er 68HCll for drive and fonnatting control one ASIC circuit for buffer and bus control and one ASIC circuit for formatter and drive functions Tape speed and all write data timing are referred to crystal controlled clocks TOC 3620 40 60 Phase Locked loop nominally 900 KHz designed to operate with the GCR code 64 KBytes standard ...

Страница 30: ...the drive top nush against a nat surface may obstruct the rubber im eller fan mounted on the c a stan motor axle The Drive occupies a half size or slim line S 1 4 slot with two standard holes for 3 mm mounting screws on both sides of the Drive chassis In addition four 3 mm standard mounting holes are located at the bottom of the Drive drive mounted horizontally See Figure 4 1 for the mechanical di...

Страница 31: ...cessary if the Drive chassis is not adequately grounded to the system chassis through the mounting screws See Figure 4 2 Correct grounding of the chassis is important in order to reduce radiated electromagnetic interference I l The Drive operated as a stand alone unit complies with FCC class B for radiated noise However incorrect grounding may violate this at the system level As a rule of the thum...

Страница 32: ...ommunication for adjustments and tests Test selection The layout of the jumper strap connector is shown below Parity Enable If closed PARI Serial Communication In IN Serlll Communlcltlon Out OUT p clal tl ts are executecllf this pin II grounded TEST OPEN OPEN OPEN OPEN OPEN OPEN OPEN OPEN 4 2 1 Selecting Drive Number The factory default drive number setting is Drive O If the Drive has to be set up...

Страница 33: ...e data cartridge is only specified up to 45 C we re commend that the bus termination option ir tside the Drive is NOT used as this will cause unnecessary heat dissipation inside the Drive To avoid this try to place the TOC 3620 40 60 Drive between other SCSI devices on the SCSI bus However if his is not possibJe we suggest that the bus is terminated with a special flat ribbon bus terminator which ...

Страница 34: ...s that easily can be staned by setting up a specific code on the select straps SELO SEL2 and by grounding the TEST pin during drive power up The coding are as follows SELl SELO Meaning OPEN OPEN Drive without Sensor Bd Bum In Test Complete Drive Run In Test OPEN CLOSED Acceptance Test SeHtes 2 CLOSED OPEN Reserved for future use CLOSED CLOSED Reserved for future use OPEN OPEN Reserved for future u...

Страница 35: ...her host operations while the SCSI bus is busy In a SCSI bus system see Figure 4 4 the Host will activate a particular peripheral device when necessary However when needed one of the other peripheral devices may take over the bus acting as a temporary host until that particular operation is completed INOTE The Drive has built in termination resistor network This network MUST be REMOVED if the Driv...

Страница 36: ...to meet the cartridge specifications above It is of course of imponance not to terminate the SCSI bus inside the Drive as this will dissipate unwanted heat inside the drive unit We recommend that the SCSI Drive is located in the middle position of the SCSI bus in which case NO Drive termination circuitry is required See Section 4 2 3 It is also possible to use specially designed bus terminators on...

Страница 37: ...TANDBERG DATA 4 8 Mounting Specifications This Page Intentionally Left Blank ...

Страница 38: ...anrtdge guides and the head positioning system Quality of tape handling Drtve mounting In the host chassis Cleaning and maintenance Cleanness of the air surrounding the Drive and tape Quality of the power supply connected to the Drive Quality of the way clata errors are treated by the formatter Operating and storage environments The Drive is designed and constructed for optimal quality to ensure a...

Страница 39: ...rior to use a cartridge should be kept for at least 24 hours in climatic conditions similar to those in which the Drive operates See also Section 5 5 Cartridge Conditioning and IMPORTANT notice in Chapter 0 With all these points in mind it is imponant to remember that errors still occur even on cenified tape The Drive is designed to handle these errors in the way described in the following paragra...

Страница 40: ...od blocks that follow have higher block numbers the retry procedure is employed The Drive t to d the bad block another two times If atlll unable to rud the bad block It tries to d the bad block nother two times this time with the he d movad a 1 4 track wldth off center If atlll unable to d the bad block It tries to d the bad block nother two times this time with the head moved a 114 track wldth of...

Страница 41: ...tioning Nles The achieveable data reliability is depending on the tape and cartridge quality In order to obtain the lowest error rate possible on a iven cartridge the cartridge should be conditioned according to the following rules before being used lefore use the cartridge shall be condhloned by exposure to the actual operating environments for at least 4 hours Aefer to Section 3 3 1 for the oper...

Страница 42: ...tandard QIC 24 QIC 120 and QIC 1S0 tape fonnats are described QIC 24 QIC 120 and QIC ISO are the standard tape fonnats for the TDC 3620 40 60 Drives Nonnally the optional QIC l1 fonnat is used only when it is necessary to read old QIC ll formatted tapes The main differences between the QIC 24 QIC 120 QIC IS0 and the QIC 11 format are No ref nce trICk II wrttten on Track 0 Only 1 byte available for...

Страница 43: ...y on nine tracks TOC 3620 QIC 24 on fifteen tracks TOC 3640 QIC 120 or on eighteen tracks TOe 3660 QIC 150 one at a time Figures 6 1a 6 1b and 6 1c show the track numbering for 9 5 and IS track l eCOrded tapes respectively Figure 6 la Track layout or the TDC 3620 Drive DI 1 Figure 6 1b Track layout or t TDC 3640 Drive ...

Страница 44: ... 10 Sta 01 bill 01 1 OlIo TNIdr I End of Ca_ 10 t c d Point 01 1 TractIs 3 5 11 13 u s Point 10 EIIII of 01_ 01 1 TIKkI 10 7 0 15 17 Figure 6 1c Track layout or the TDC 3660Drive Recording is done serially on one track at a time starting with Track O Even numbered tracks 0 2 etc are recorded from BOT Beginning Of Tape towards EOT End Of Tape while odd numbered tracks 1 3 etc are recorded from EOT ...

Страница 45: ...mode tape recording 6 4 Recording Method Information is recorded on the tape using the NRZI NON RETURN to ZERO change on ONEs method where each bit is recorded as a flux reversal 0 bits give no flux transitions on the tape but are detected by measuring the distance between bits flux reversals To avoid long distances on the tape without any flux changes strings of 0 bits only the information to be ...

Страница 46: ...E2 E1 EO Table 6 2 shows the conversion from OCR to normal data nibbles Encoded information Encoded Nibbles I Hex Information 1 nd 2 Value ro 1 0 0 1 0 0 0 1 Data Field File Mk Blks 1 1 0 0 1 0 0 1 1 1 Block Marker E4 EO 1 0 0 0 0 1 0 0 1 1 0 0 1 9H 0 0 1 1 0 1 0 1 0 1 0 1 0 AH 0 1 0 1 1 1 0 1 1 BH 1 0 1 0 1 0 1 0 1 1 0 1 1 1 0 1 DH 1 0 1 1 0 0 1 1 1 0 1 1 1 0 EH 1 0 1 1 1 0 1 1 1 1 1 1 1 1 FH 1 1...

Страница 47: ...ns The encoded information is recorded serially by encoded bit and by character starting with bit E9 in each character Tracks are recorded in a sequential order starting with Track O Encoded bit positions _ 56789012345678901234 Forward tape motion BOT EOT Resulting recording direction ...

Страница 48: ... Preamble consists of a recording at the highest recording density nominally 394 ftpmm 10 000 ftpi The Preamble is used to synchronize the veo Voltage Control Oscillator in the read electronics with the data frequency Three preamble types are recorded Normal Elongated and Long The Normal Preamble is recorded at the beginning of every block on the track except for The first blOCk on the track The f...

Страница 49: ...It contains a minimum of 15 000 and a maximum of 30 000 flux transitions recorded at the highest recording density Data Blocks File Mark Blocks 6 7 2 Block Marker The Block Marker identifies the end of the preamble and the beginning of the data field on every block It consists of a fixed bit pattern E9 E8 E7 E6 E5 E4 E3 E2 E1 EO 1 1 1 1 1 0 0 1 1 1 Bit E9 is recorded first 6 7 3 Data The data fiel...

Страница 50: ...ibble Track Number Control Nibble Block Number Block Number Figure 6 4 Block address layout The Track Number is a binary number encoded according to the rules given in Section 6 5 This is the most significant nibble of byte 1 in the Block Address II is encoded according to the rules given in Section 6 5 The control nibble has the following layout Byte 1 7654 0000 Normal Data Block or File Mark Blo...

Страница 51: ... 6 8 6 7 5 eRC Cyclic Redundancy Check Immediately following the Block Address a Cyclic Redundancy Check CRC character is recorded using the following polynominal G x x16 x12 x5 1 The CRC generation is performed prior to the byte encoding starting with the most significant bit in the first byte in the Data field ending with the least significant bit of the Block Number The two CRC bytes are encode...

Страница 52: ...bad spots on the tape or other errors some blocks may be detected as bad one or more flux reversals not detected correctly These bad blocks are automatically rewritten funher down the tape as shown in Figure 6 6 Block 1 Block Block n 1 Block n 2 First First First Write Rewrite Rewrite Recording direction Figure 6 6 Track layout after rewriting ofbad blocks In Figure 6 6 Jet us assume that b ock n ...

Страница 53: ...the same block number are detected the Drive will only transfer the data contents of me first of these blocks to the Host 6 9 File Mark Blocks File Mark Blocks are used to separate logically different sections of data This is controlled from the Host The QIC 24 the QIC 120 and the QIC 150 proposals also define a file mark to be recorded at the end of the recorded area The Host should issue a Write...

Страница 54: ...150 formatted tapes To make the Drive able to differentiate between the two 15 or 18 tracks a unique Control Block will always be written as the first b ock on all QIC 150 18 track formatted tapes This is done by the Drive when it is selected to write 18 tracks It is redundant to the Host and it is used by the Drive only during reading The Control Block is NEVER transferred to the Host 6 11 Gaps E...

Страница 55: ...is ready in the buffer or until the limit for rewrites is reached In this case an Elongated Postamble is written and the tape is halted The Elongated Postamble will always be recorded at the end of a write operation also after the last File Mark 6 14 Data Append After a write underrun situation see Section 6 13 or when the Host wants to append data to a recorded cartridge the Drive will stan the o...

Страница 56: ... past the LP hole The last block of data for interchange written on these tracks prior to switching to the next track is recorded somewhere between 2 S mm 0 1 ft and 100 mm 4 before the LP hole measured from the center of the hole On Tracks 3 and 5 data may be recorded past the LP holes No data for interchange will be recorded beyond a point 685 mm 27 past the LP hole For the QIC 120 format the di...

Страница 57: ...TANDBERG DATA 6 16 This Page Intentionally Left Blank Track Tape format and Encoding Specifications ...

Страница 58: ...nctions are completely transparent to the Host 7 1 1 Write Reference Track If the tape is positioned at Beginning Of Tape the Write Refer ence Track function is always perfonned after a Write command is received The Write Reference Track is done internally in the Drive and is transparent to the Host The Reference Track is placed between the BOT Beginning Of Tape holes and the LP Load Point holes a...

Страница 59: ...se of different tolerance in head position there will be no guarantee that the QIC ISO actually can be read During a seek Reference Track the Drive will use the following scheme to detect the tape format See NOTE After power up the Drive will calibrate the head position by entering the highest possible position From this position the offset to any tape position can be calculated relatively accu ra...

Страница 60: ...fIrst track Track 0 the Drive also enables the Erase function This assures that old data on the tape is erased in front of the write head The number of datablocks according to the Write command is written when the data is received into the drives internal data buffer After the Drive have fInished writing the fIrst track on the tape the Erase function is disabled This is done because the Erase func...

Страница 61: ...e PEW point is a position calculated to be approximately SO inches in front of the Early Warning hole on the tape At the PEW position the Host can be sure that all data trans ferred to the Drive will be correctly written to the tape This position must be regarded as the absolute limit for normal Write operations However the Host may continue to write a few datablocks or Filemarks on the tape This ...

Страница 62: ... the Drive informs the Host with CHECK CONDmON 7 2 6 Recoverable Write Error Rewrite During Write defective blocks may be written These erroneous blocks are detected by the Drive s built in Read After Write function Errors are detected by using the so called CRC Cyclic Redun dancy Check algorithm during Read This CRC result is com pared with a CRC value written on the tape during Write Due to the ...

Страница 63: ... procedure is totally 1I aI1sparent to the Host 7 2 7 Unrecoverable Write Error If the Drive has tried to rewrite the same block 16 times without succeeding the Drive will abon the Write command and send CHECK CONDmON This should be treated as a fatal error situation where either the Drive or the tape cartridge is failing due to damage ...

Страница 64: ...ape fonnat See funher details about the Seek Reference Track operation in Section 7 1 2 Read Reference Track This seek operation is fully transparent to the Host 7 3 2 Read From a Position on the Tape A Read command can be executed from any position on the tape At any position except Beginning Of Tape the track position is known from the previous commands A new Seek Reference Track is not necessar...

Страница 65: ...the block will be read correctly and the Read routine will continue If the block is not detected and the block numbers are increased showing that the block is not rewritten the following Reread algorithm is performed The Drive will reposition and try to read the same block twice The Drive will move the head 1 4 track width upwards and try 10 read the same block twice The Drive will position the he...

Страница 66: ... 8 signal lines Nine control the bus nine are used for an eight bit bidirectional data interface with odd parity All communication on the bus is performed synchronously by means of the REQ ACK handshake The Drive should be connected to the bus with a 50 pin flat ribbon connector Single ended drivers and receivers allow a maximum cable length of six meters 20 feet The SCSI Hard Reset option is impl...

Страница 67: ...d be terminated in both ends with 220 ohms to 5 V and 330 ohms to ground See NOTE in Section 4 3 The signals from the Drive to the controller have the following output charactertstics Signal assenion logical 1 Signal deassenion logical 0 Signal between 0 0 and 0 4 V with 48 rnA sinking capability Signal between 2 5 and 5 25 V The signals from the Initiator to the Drive must have the following char...

Страница 68: ...h a SO pin ribbon cable The single ended option is used The signal pin numbeT and names are listed below Pin GND Return Pin Signal Name 2 1 Data Bus 4 3 6 5 8 7 10 9 12 11 14 13 16 15 Data Bus 18 17 Data Bus Parity 20 21 24 23 26 0 25 28 27 30 29 32 31 Attention 34 33 36 35 Busy 38 37 Acknowledge 40 39 Reset 42 41 Message 44 43 Select 46 45 Control Data 48 47 Request 50 49 InputiOutput I TE donal ...

Страница 69: ...s with respect to the Initiator Assenion indicates input to the Initiator A signal driven by the Target indicating the message phase A signal driven from the Target indicating a request for an REQ ACK handshake A signal driven by an Initiator to indicate acknowledgement of an REQ ACK handshake A signal driven by an Initiator indicating that a message is available for the Target An or tied signal w...

Страница 70: ...ize the Bus Free Phase devices have to test that both BSY and SEL are not asserted simultaneously within a deskew delay and that the Reset condition is not active 8 5 2 Arbitration Phase Optional The SCSI bus allows multiple host configurations To avoid bus crash situations in a configuration like this the devices have to arbitrate for the bus If more than one device is requesting the bus simultan...

Страница 71: ...fter a 90 ns delay it also assens SEL The Target will respond by asserting BSY and the Initiator should then deassen SEL For systems using arbitration the following must be done In this order asy SEL ATN lisa oCJD 1211 U r I I __ r 1 r i i min 400ns REQ min a11 ___ it l_ loCK min ana r I DATA BUS lI IIn Ons 0u18yt ___ Figure 82 Arbilralion Selection and Message Out Phases Parity is valid for this ...

Страница 72: ...f time it will send the Deselect Message In and release the bus When the Target wants contact again it will have to go through the Reselection Phase This Phase is similar to the Selection Phase except that the O line is assened Before the Target can reselect It must first go through the Arbitration Phase to gain control of the bus Then the following Quence takes place 1IUQe In BSY sa _ ATN Msa _ _...

Страница 73: ...lock by assening REQ The Initiator responds by placing the first byte on the bus and assening ACK The Target notices this and deasserts REQ The Initiator should then deassen ACK The first byte is now transferred The Target will continue ask for additional bytes until the entire Command Descriptor Block is transferred and the Command Phase is ended BSY SEL ATH USG oCID 4 InI 400 110 4 I IIn On REO ...

Страница 74: ...a Exchange Phase includes both the Data Out Phase and the Data In Phase In both cases the ern and MSG lines will be deasserled and BSY assened The Data Out Phase allows data to be transferred from the Initiator to the Target In the following way BSY SEL ATN usc c o 1 0 REQ ACK DATA BUS COOns 4 m n ons l_____ _____ I r L t4 rrun ns _ _ _ 1 l hS Oa a Out laS Oata 0 Figure 8 5 Dara Out Sequence IThis...

Страница 75: ... 8 6 Data In Sequence This completes the byte transfer This cycle is repeated until the last data byte has been transferred NOTE The data transfer for the Drive is done in hardware and has a transfer rJte of about 1 5 Mbytes sec 8 5 7 Status Phase The Status Phase is entered when the Drive has t ompleted a command execution or if a non recoverable error has occurred In this phase BSY CfD and I O w...

Страница 76: ...O and the Initiator can deassert ACK 7 The Message In Phase terminates when the Target deasserts MSG B 11 Hardware Interface la s a Message In Phase The Message In Phase Is used In three ways SlaIUI Phlose Meswge In PIIUe I B s fref BSY r SEL ATN MSG r c o r 4 mon 400 Fl I O U REQ i I I i r r ACK rnin 4511 DATA tSlmus Byle MeuageIn Byle BUS Figure 8 7 Status and Message In Phases The Drive will ge...

Страница 77: ... the mess age byte on the bus and assens ACK 6 The Target then deassert REO and the Initiator can deassert ACK 7 The Message Out Phase terminates when the Target deassens MSG 8 12 Hardware Interlace IS 5 9 Message Out Phase The Message Out Phase Is used In the following way 1 When an Initiator signals that it supports deselection 2 When an Initiator has detected a parity error 3 When it abons a co...

Страница 78: ...is marked with 0 1 in Table 8 2 below The ARBITRATION and SELECTION phases are controlled by the Initiator After the Target is selected it should select the correct bus phases The ARBITRATION and RESELECTION phases are controlled by the Target Bus Phase BSY SEL MSG C O 110 Bus Free 0 0 0 0 0 Arbitration 1 011 0 0 0 Selection 011 1 0 0 0 Reselection 011 1 0 0 1 Command 1 0 0 1 0 Data Out 1 0 0 0 0 ...

Страница 79: ...Drive detects the Unit Attention Condition The first command sent by each Initiator to the Drive after a SCSI bus reset condition causes the Drive to send a Chet k Condition status message The Drive also sets the Sense key in the Extended Sense Byte to UNIT ATTENTION Before removing the tape cartridge the Initiator should issue an Unload command which positions the tape at EaT or BOT If a cartridg...

Страница 80: ...t Condition can abon any phase and force the bus to the Bus Free Phase The Phase Sequence for systems with or without Arbitration are shown in the figures below Figure 8 9 Phase Sequencing or systems using Arbitration BUS FREE phase RESET condition DATA or STATUS or Figure 8 10 Phase Sequencing for non arbitrating systems ...

Страница 81: ...TANDBERG DATA 8 16 Hardware Interface This Page Intenlionally Left Blank ...

Страница 82: ...of a six byte Command Descriptor Block COB containing the command code and in most cases the necessary parameters to execute the command The basic format of the COB is shown in Table 9 1 The particular COB format of each command is described in the fol lowing sections When more parameters are needed than there is space for in the COB the parameters will be sent to the Drive as data 6 5 4 3 2 1 o C...

Страница 83: ...t is set If both bits are set a LINKED COMMAND COMPLETE WITH FLAG message is requested for this command in a group of linked commands If only the Link bit is set the LINKED COMMAI TD COMPLETE message will be used instead In many cases the specific COBs will contain reserved bits and bytes Those bits are reserved for future extensions and should be set to zero This allows upward expansion of host s...

Страница 84: ...ed Data 0 14 Release Unit 0 17 Request Block Address V 02 Request Sense M 03 Receive Diagnostic Results 0 1C Reserve Unit 0 16 Rewind M 01 Seek Block V OC Send Diagnostic 0 10 Space 0 11 Test Unit Ready 0 00 Verify 0 13 Write M OA Write Data Buffer 0 3C Write Filemark M 10 INOTE This command is implemented for Tandberg Data internal use only Type definition in the proposed SCSI Common Command Set ...

Страница 85: ... pan operates as an Initiator for the other SCSI device and also for the internal data transfer part The data transfer part operates much similar to the Drive wben executing nonnal Read and Write commands Typically the Copy command is used to move data to or from a bard disk The Drive can then manage a full BACKUP or RE STORE operation Some Copy command features are Sequential Access to Direct Acc...

Страница 86: ...orresponds to 256 Segment Descriptors 12 bytes long and a single Header Flag Link These two bits have their usual meaning BYTE BIT 7 00 01 02 03 The Parameter Block The Parameter Block has two pans First there isa four byte header block which contains the Copy Function Code One or more Segment Descriptors are provided after the Header Up to 256 Segment Descriptors are supponed The Segment Descrip ...

Страница 87: ... Reserved SourcelUN Dest Controller 10 Reserved Dest lUN Sequential Access Device Block Size MSB 02 Sequential Access Device Block Size lSB 00 Direct Access Device Number of Blocks MSB Direct Access Device Number of Blocks Direct Access Device Number of Blocks Direct Access Device Number of Blocks lSB Direct Access Device logical BJockAddress MSB Direct Access Device logical Block Address Direct A...

Страница 88: ...riable number of data blocks A Block Size of 1024 bytes will lead to a 1 2 relationship between number of Direct Access Device block counts and the Drive block counts etc A zero value means copy no data for this Segment This is the address of the first block on the Direct Access Device to be copied Note that the address must fit into the 21 bits of the standard 6 byte ReadIWrite command blocks use...

Страница 89: ... used When processing a Segment Descriptor the TOC 3620 40 ffJ Drive will issue a sequence of ReadlWrite commands to the direct access device The Drive will request only small amounts of data at a time data already in the Drive s data buffer or data with reserved space in the buffer This means that the di rect access device does not have to support disconnection It also means that the Drive will c...

Страница 90: ...es mean that the last ReadIWrite command will request less blocks than indicated by the Copy Threshold S Points 1 2 3 and 4 are repeated for each Segment De scriptor in the Segment Descriptor List NUTt In future fmnware releases the mc 3620 40 60 Drive may not check the block length for every Segment Descriptor as long as the direct access ID and LUN are the same as for previous Segments ...

Страница 91: ... does not sup port the Read Capacity command it will tenninate this command with a Check Condition status The Drive will then use the sec ond method to determine the block size First any pending sense infonnation are cleared by issuing a Re quest Sense command 4 bytes of sense data are requested Then a Read command with the Transfer Length set to 1 read 1 block is sent to the direct access device ...

Страница 92: ...command with Check Condition Status 2 Sets the VADD bit Sets the Sense Key in the Extended Sense Block to the code that describes the error condition 3 Sets the Segment Number in the Extended Sense byte 01 to the number of the segment where the error occurred 4 Updates the Information Bytes with the difference be tween the requested and the actually processed blocks bytes for the current segment S...

Страница 93: ... tape is to small to fill a complete direct access block This can only happen during RESTORE if the data transfer part of the Drive encounters an unexpected Filemark End of Recorded Area BLANK CHECK or a Bad Block All data up to the last resid ual block s will be transferred to from the direct access device The last incomplete block is not transferred Check Condition Status is sent to the original...

Страница 94: ...Length is then set to 18 17 nonnal additional sense bytes plus the Target Status Byte IfTarget Sense Data is available the Additional Sense Length indicates the num ber of bytes available like this Target Sense Bytes Additional Sense Length 18 7 Updating the Source Sense Pointer to indicate the source Target Status Byte This pointer is relative to the flrst byte of the Extended Status Block Possib...

Страница 95: ...e Drive sends Check Condition Status to the original Initiator The Ini tiator should then Request Extended Sense Data from the Drive The Sense Key will read Copy Aborted The Sense Data Block will have an unmodified copy of the direct access device Status Byte and Sense Data if available The action taken by the TOC 3620 40 60 Drive in case of an er ror detected in the Drive itself is very similar T...

Страница 96: ...d OSH IBYTE BIT 7 5 4 00 0 0 0 0 I 3 2 0 0 1 0 0 0 0 0 I 0 I 3 2 1 0 0 01 Logical Unit Number I Logical Block Address MSB 02 Logical Block Address 03 Logical Block Address LSB 04 Number of Blocks 05 0 0 I 0 0 0 0 I 0 I Write OAH I BYTE BIT 7 5 4 3 2 00 0 0 0 0 I 0 01 Logical Unit Number I Logical Block Address MSB 02 logical Block Address 03 Logical Block Address LSB 04 Number of Blocks 05 0 0 I 0...

Страница 97: ...city 25H I BYTE BIT 7 6 5 4 3 2 1 0 00 0 0 1 0 I 0 1 0 1 01 Logical Unit Number I 0 0 0 0 0 02 0 0 0 0 0 0 0 0 03 0 0 0 0 0 0 0 0 04 0 0 0 0 0 0 0 0 05 0 0 0 0 0 0 0 0 06 0 0 0 0 0 0 0 0 07 0 0 0 0 0 0 0 0 08 0 0 0 0 0 0 0 0 09 0 0 J 0 0 0 0 I 0 I 0 ...

Страница 98: ... Reserved Reserved Reserved X I Reserved I Flag I Link This bit must be set to 1 bit 0 in byte 1 If not the Drive will return Check Condition status The Sense Key will read Illegal Request The Erase command causes the Drive to erase the entire tape When fmished the tape will be positioned at BOT The Drive may disconnect during the execution of this com mand ...

Страница 99: ...icates the maximum number of bytes that will be transferred The Drive will tenninate the Data In phase when allocation length bytes have been transferred or when all available Inquiry Data have been transferred to the Initiator whichever is less A Check Condition status will never be reponed for this com mand If an Inquiry command is received from an Initiator with a pending Unit Attention Conditi...

Страница 100: ...n E 14 Vendor Identification R 15 Vendor Identification G 16 Product Identification 17 Product Identification T 18 Product Identification 0 19 Product Identification c 20 Product Identification 21 Product Identification 3 22 Product Identification 8 23 Product Identification 0 24 Product Identification 0 25 Product Identification 26 Product Identification 27 Product Identification 28 Product Ident...

Страница 101: ...re Identification R Software Identification E Software Identification A Software Identification T Software Identification E Software Identification 0 Month MSB Month LSB Day MSB Day LSB Year MSB Year LSB These two bytes denote the option level of the software ASCII coded i e a customer specific f1 Illware will have an option level O The standard software will have Option Level 0 These three bits c...

Страница 102: ...tus will be returned with the Sense Key set to megal Request and the Sense Code to In valid Command When this bit is set and the EOT bit is not set the Drive per fonns a retension pass before the LOAD or UNLOAD command is completed If the EOT bit is set the retension option is ig nored Retensioning means moving the tape to EOT and then back to BOT The purpose is to remove possible tape tensions th...

Страница 103: ...uested is specified in the Length of Parameter List byte Byte 04 above If this bit is set the selected mode is permanent i e the Drive will also remember the configuration during power down and reset The parameter list contains of a four byte header followed by one Block Descriptor page of 8 bytes and 12 bytes of additional Mode Select Parameters in total 24 bytes The Parameter List is specified a...

Страница 104: ... Drive BACKUP The Buffered Mode is always active when moving from one Segment Descriptor to the next This means that the Drive will stan processing a new Segment Descriptor as soon as the data from the previous Segment Descriptor has been transferred into the data buffer When the entire Copy operation has been completed all data from the last Segment Descriptor has been transferred into the buffer...

Страница 105: ... at Power uplReset This is controlled by the saved Mode Select parameters in the EEPROM Use the SMP bit in the Mode Select command to save make pennanent the selected tape format Number of blocks in the buffer before tape write stans The Write Threshold specifies the number of blocks that should be ready in the buffer before the tape stans and the actual Write operation can commence Number of free...

Страница 106: ...e maximum value depends on the block size of the direct access device Not more than 32 KBytes of data should be transferred during a single Read Write command This corre sponds to a maximum Copy Threshold of 128 for 2S6 byte blocks 64 for Sl2 byte block 32 for 1024 byte blocks 16 for 2048 byte blocks and 8 for 4096 byte blocks If the total number of blocks to transfer given by the current Copy Seg...

Страница 107: ...set to one the Sense Data will be in Extended fonnat The VADD bit is zero The Segment Number is zero Byte 02 holds the FM and EOM bits and also the Sense Key All Information Bytes will be zero The Additional Sense Length is set to 8 Byte 14 holds the Error ClasslError Code Byte 15 holds the IDC 3620 40 60 Drive Extended Error Code EXERCD All other bytes will be set to zero This field controls the ...

Страница 108: ... makes it possible for the Initiator to read the Drive s configuration The configuration data are sent as data with this fonnat 6 5 4 3 2 o Sense Data Length 00 IMDTY WP I Reserved I BM I Speed Code 00 Length of Extended Descriptor List 08 Block Descrlptor s Density Code Reserved 00 00 Reserved Reserved Block Sjze MSB 02 Block Sjze LSB 00 AddHlonal Mode Select Parameters Vendor Unique Page Code 00...

Страница 109: ...rt good status or not as soon as the data has been transferred into the Drive s Data Buffer cache for the write and verify commands BM set indicates that good status should be reported at this time If BM is not set the Drive will only return good status after the data blocks have been actually written or verified Density Code This byte specifies the tape format that has been found on the last tape...

Страница 110: ...fer Size Forced Streaming Count Bus Threshold Copy Threshold Nonnar Sense Threshold Copy Sense Allocation Load Function Power Up Auto Load Auto Re tension Delay 9 29 For the description of these bytes see Section 9 3 5 Mode Select Software Interface ...

Страница 111: ...nt LED Light Emitting Diode will be used to indicate Can ridge in Use By issuing this command with the PREY bit set Prevent Media Removal the green front LED will be lit When issuing the command with the PREY bit cleared the LED is turned off unless the tape cartridge is loaded The LED is turned off when the Drive is reset A LoadlUnload command issued after a Prevent Media Removal command does NOT...

Страница 112: ...ense Key to NO SENSE If all the requested data blocks are not read the Valid Address bit will be set and the difference be tween the requested and the actually read number of blocks will be set in the Information Bytes If logical End Of Media EOM is detected during the read operation the Drive sends the Check Condition to inform the Initiator In the Extended Sense Status the Error Class Error Code...

Страница 113: ...has occurred the read operation will begin with the block following the erro neous block If the disconnect option is enabled the Drive may disconnect from the Initiator during the execution of this command 9 3 8 1 Read Command Error Conditions General error conditions during tape operations are listed and described in Appendix B Error ClasslError Code Read Error Read EOM 34 The TDC 3620 40 60 Driv...

Страница 114: ...ive does not disconnect for this command The requested block length will be delivered as six data bytes Since the block length is fixed to 512 bytes for QIC ll QIC 24 QIC 120 and QIC 150 the command will always return 200 hex for maximum and minimum block length The layout of the data bytes is Reserved Maximum Block length MSB 00 Maximum Block length 02 Maximum Block Length lSB 00 Minimum Block le...

Страница 115: ...ned Read Data Buffer data An Allocation Length of zero indicates that no Read Data Buffer data will be transferred This condition will not create the Check Condition status Any other value indicates the maximum num ber of bytes to be transferred This data is to be used by the Ini tiator for comparison with the data pattern sent during the Write Data Buffer command Up to 65 535 bytes may be request...

Страница 116: ...mmand after the Read Data Buffer command 2 Selects without allowing disconnection and links the Write Data Buffer and the Read Data Buffer commands together The Available Length of data bytes returned by the Drive may be up to 65 531 bytes 64 Kbytes minus a 4 byte header or the Drive s maximum buffer size whichever is less If the Allocation Length of CDB is too small to transfer all of the Availab...

Страница 117: ... a situation where it is impossible to write more data on the tape In this case the Initiator can retrieve the non written data from the Drive s Data Buffer The data will be presented in the same order as they were written into the buffer If the buffer contains less than the specified number of blocks the Check Condition will be returned In the Extended Status Block the EOM and the VADD bits will ...

Страница 118: ... is reserved by another Initiator the command will be ignored and GOOD status reo turned Releasing the Third Party Reservation Release requires the fol lowing conditions 1 The THP option see Reserve Unit Section 9 3 14 must be used 2 The same Initiator must request the release 3 The Third Party Reservation Release option Byte I bits 1 3 must be set 4 The device to be released must be the one speci...

Страница 119: ...uest Block Address command requests the Drive to transfer the current tape block address to the Initiator An Allocation Length of zero indicates the command s default length is to be used When non zero the number of bytes speci fied in Allocation Length up to a maximum of 3 bytes will be transferred Request Block Address Data Format is shown in the table be low 6 5 4 3 2 o 0 0 0 I Block Addresss M...

Страница 120: ... This is controlled by byte 04 in the command block and the Normal Sense Threshold stored in the EEPROM If the No of Bytes Allocated byte 04 in the command block has a higher number than the one stored in the Normal Sense Threshold see Mode Select Extended Sense format will be returned If the value of No of Bytes Allocated is equal or less the one stored in the Normal Sense Threshold Nonnal Sense ...

Страница 121: ...ense Block is BIT 7 6 5 4 3 2 o VADD I ERCL I ERCD 0 0 0 I Information Byte 1 MSB IInformation Byte 2 Information Byte 3 LSB The meaning of this block is This bit is set if the Information Bytes contain valid infonnation This field specifies the Error Class Bits 6 5 4 Error Class 0 0 0 Drive errors 0 0 1 Drive errors 0 1 0 System related errors 0 1 1 Vendor uniQue error conditions This field speci...

Страница 122: ...ass 2 Errors are System Related Errors Code Error Description 20 Invalid command The issued command is not implemented Class 3 Errors are Vendor Unique Error Conditions Code Error Description 30 Unit attention A Unit Attention condition see Section 7 5 2 Indicates that the cartridge has been changed and a Load command given or the Drive may have been reset by the Bus Device Reset message since the...

Страница 123: ...ter the Initiator first having issued the Request Sense com mand see Section 9 3 14 This Block will repon all necessary information about errors and parameters before letting the Ini tiator perform adequate error handling The layout of the Sense Data Block is as follows I 5 4 3 2 1 o I 1 1 1 I 0 0 0 0 Segment Number IEOM I 0 0 I Sense Key Information Byte 1 MSB Information Byte 2 Information Byte ...

Страница 124: ...y the Copy command the Addi tional Sense Block bytes 08 OD will have the meaning shown above The meaning of these bytes under the Copy command are described in Section 9 3 1 Copy command The meaning of the Extended Sense Block is This bit is set if the infonnation bytes contain valid infonnation Contains the current segment number if the Extended Sense in fonnation is in response to a Copy command...

Страница 125: ...logical unit When non zero this byte will read 25 This byte specifies the byte number relative to the first byte of Sense Data related to the beginning of the Destination Status Byte and Sense Data A zero 0 value indicates that no status byte or sense is re turned for the destination logical unit When non zero this byte will read 25 Extended Error Code is internal to the Drive and reflects all pos...

Страница 126: ...written blocks left in the data buffer af ter a fatal error has occurred during a Write operation This status byte is returned from the source or destination device when a data transfer error has been detected during a Copy operation In case the Copy operation is performed by a TOC 3620 40 60 Drive this byte will always read 02H Check Condition These are the Sense Bytes returned from the source or...

Страница 127: ...NIT AITENTICN A Unit Attention Condition occurred See Section 7 5 2 This status indicates that the cartridge has been removed since the last com mand It is retumed the first time a command is given after the cartridge has been removed The condition is cleared for the next command from the same Initiator Unit Attention is given to all SCSI devices that subsequently issue a command to the Drive 7 DA...

Страница 128: ...Jr additional data blocks are appended after the Drive has reponed EOM and there is not sufficient space left If this error situation occurs the non written blocks can be reclaimed by issuing the Recover Buffered Data command E MISCOMPARE Used by the Verify command to indicate that source data did not match the data read from the tape F Reserved ...

Страница 129: ...or the Drive will send a RESERVA TION CONFLICT status and disconnect from the requesting Initiator THP Third Pany The Third Pany Reservation option Byte I Bit 4 allows a Reservation option LUN to be reserved for another device If this bit is set an Ini tiator is allowed to reserve the Drive for the SCSI bus device specified in the Third Pany 10 field Byte I Bits 1 to 3 This option is intended for ...

Страница 130: ...on as the rewind is initiated If lMED is not set status will not be re turned until the tape has stopped at BOT If the IMED option is used and a new command is received during the rewind opera tion that command will be executed immediately after the rewind is completed If the lMED bit is set the LINK bit must be zero 0 or else a Check Condition Status will be returned with the Sense Key set to Ill...

Страница 131: ...an be used to position the tape at the End of Recorded Area and then by issuing Space Reverse One File Mark to the position in front of any directory blocks A block address if zero 0 will cause Check Condition Status with the Sense Key set to Illegal Request and the Error Code to Invalid Command If the specified block address is not found on the tape a Check Condition Status is returned and the Se...

Страница 132: ...un this test an unprotected cartridge must be insened and loaded The command will return with GOOD status if no errors occurs Else Check Condition will be set By issuing a Request Sense command the Extended Sense Block will give information about the problem The EXERCD byte will suppon the detailed information See Appendix A for explanation of the different EXERCD error codes When the STest bit is...

Страница 133: ... the Parameter Block 6 4 3 2 1 o I Operation Type 00 No of Tracks to test No of Blocks pro file MSB No of Blocks pro file LSB File Rewrite Limn Total Rewrne Limn File Reread Limn Total Reread Limn This bit is reserved for TO internal use and should always be set to zero O NOTE Acceptance TestlSelftest 2 can be run with changed parameters This is basically the same test as the Selftest 2 described ...

Страница 134: ...ue in the Count field causes no tape movement A negative value n 2 s complement notation in the Count field causes reverse tape movement over n blocks or filemarks ending on the Beginning Of Media side of the last block or filemark If a filemark is encountered while spacing over blocks tape movement is stopped The tape is positioned on the End Of Me dia side of the filemark if movement was in the ...

Страница 135: ...r filemarks spaced over The Drive will move the tape forwards from the current position until detection of n Sequential filemarks n 0 causes no tape movement Only logical forward towards End of Media search operations are permitted A negative value 2 s complement specified in the count byte will cause a Check Condition In the Sense bytes Illegal Request will be reported If the logical End Of Media...

Страница 136: ...sts whether the requested unit is ready or not This is not a Selftest request command If the Drive is ready for a correct medium access command without returning Check Condition Status this command will return GOOD status If not Check Condition will be returned A Request Sense com mand can be issued to obtain detailed information why the Drive is not ready The Drive does not disconnect during the ...

Страница 137: ... case In case of a mismatch the Drive terminates the Verify command and informs the Initiator by setting Check Condition In the Ex tended Sense Bytes the VADD bit will be set the Sense Code will be set to MISCOMPARE and the Sense Key to MISCOM PARE The number of unverified blocks will be available in the Information bytes The tape will in this case stop after the faulty block If an uncorrectable d...

Страница 138: ...e s data buffer The Drive handles the Verify command very much like a Read command except for the transfer of data which runs in the opposite direction from Initiator to Drive This means that a buffered mode effect is always present when the Drive executes a Verify command The Drive may disconnect during the execution of this com mand 9 3 21 1 Verity Command Error Conditions General error conditio...

Страница 139: ...fference between the requested number of blocks and the number of blocks actu ally written will arrive in the Information Bytes Due to the above described feature the Drive s data buffer will be empty It is therefore no need to perform the Recover Data Buffer com mand After the Drive has reponed EW on the last track as described above the Initiator may continue to write blocks on the tape un til t...

Страница 140: ...ssure that all data are written correctly If the Drive is in the Non buffered Mode sta tus will not be returned until the data are written on the tape or if a Check Condition has occurred For Mode configuration see 9 3 5 Mode Select NOTE 1 To be compatible with the QIC 24 QIC 120 QIC 150 tape formats it is recommended to terminate a recording with a filemark NOTE 2 To achieve streaming operation t...

Страница 141: ... not be accessed during the execution of this com mand The Byte Transfer Length includes a four byte header and the Write Data Buffer data Up to 66 535 bytes may be transferred consisting of four bytes of header and up to 65 531 bytes of data A transfer length of zero indicates that no data transfer will take place This condition will not create the Check Condition status If the transfer length is...

Страница 142: ... con tents of the Drive s data buffer to be written to the tape This bit is valid if the Drive is in the Buffered Mode see 9 3 5 Mode Select When this bit is set and the Drive is in Buffered Mode the Write Filemark command will return Completion Status immediately after being received This makes it possible to write fllemarks in streaming mode If the IMED bit is cleared Completion status will not ...

Страница 143: ...e Reserved The coding is as follows Bits 4 3 2 1 Meaning 0 0 0 0 Good Status the requested operation was completed successfully 0 0 j 1 Check Condition an abnormal condition has occurred The Initiator should issue the Request Sense command to get further information See Section 9 3 4 0 1 0 0 Busy Status the Drive is busy executing a command For instance the Rewind command when the IMED option has ...

Страница 144: ...rive will re lease the bus as for the Command Completed message How ever now the Drive will reconnect later in order to complete the operation See Section 7 4 4 for the Reselection Phase A Save Data Pointers message is always sent prior to this message This message is used in the Reconnection Phase to inform the Initiator that the Drive has reconnected This message is used to indicate the completi...

Страница 145: ... Set if the Initiator can suppon Disconnection and Reconnection Bits 0 2 Specifies the LUN address of the Drive The IDENTIFY message is only valid during the Selection Phase Initiator Detected The Initiator has detected a parity error during the information Error transfer phase This will cause the Drive to terminate the current operation with Check Condition status In the Extended Sense the Sense ...

Страница 146: ...nated and Check Condition Status sent The Request Sense block will tell the number of blocks NOT transferred to the buffer If the number of blocks in a data transfer sequence is less than n parity will be checked and reponed at the end of the transfer 9 7 1 Generallnformation When reading data on the bus the Drive will check for a parity error if the PARI pin is grounded If the Drive detects parit...

Страница 147: ...TANDBERG DATA 9 66 Software Interface This Page Intentionally Left Blank ...

Страница 148: ...ption 1 EPROM Checksum Test 2 Scratch Pad RAM Static RAM Test The static RAM is tested by writing and reading 55H and AAH data patterns to all RAM cells 3 Drive Controller Test The hardware for Write and Read formatting will be tested The Drive Controller chip is placed in digital loopback mode and 16 bytes of data is fed into the Write Sequencer through the microprocessor data pon The data is rea...

Страница 149: ... is not working properly Time consumption is about 35 sec ifa 64 KBYte buffer is supported Next the RAM addressing is checked The buffer is filled with OOH and one byte is loaded with FFH The rest of the buffer is compared with OOH If an error is detected the buffer is tested again to find out if the error is located in the high or the low nibble Other digital circuitry like the Address Decoding l...

Страница 150: ... has occurred once the error information will be stored in the EEPROM so that it can be reponed even after power off A new Burn In test can only be staned after this information has been cleared This can be done with special equipment only NOTE Only error messages 56 to 61 will be reponed during the Burn In test 2 Production RUN IN Test For Internal use only This test is used to exercise complete ...

Страница 151: ...1 l is run Next test is a WriteIRead test Two tracks are written in files of 700 blocks Between each file the tape stops and backspaces before a new file is appended Data Append is included to test the Erase circuitry The data pattern in each block alternates between three patterns One block is written with a block count pattern the next with 29H pattern and the last with 60H pattern This sequence...

Страница 152: ... 40 60 Drive Head and Motor wear When the test is staned the tape is loaded and the Head is positioned on Track O The tape moves for about 5 seconds and stops After about 1 second delay the tape starts to move again This sequence is repeated indefinitely At EDT and BOT the tape move direction is reversed Every time the tape stops the Head is moved about half a track width up or down in order to sp...

Страница 153: ...ce of the head Even small scratches may damage the head ermanentJ Always clean the head immediately after using a new cartridge and if large numbers of rewrite or reread operations are performed Use only cenified quality canridges for the TOC 3620 40 60 Drive Do not use worn or audibly noisy cartridges Cartridges which repeatedly require rewriting of large numbers of blocks per track should also b...

Страница 154: ...w shows the TOC 3620 40 60 Drive s error messages accompanied by the EXERCD Hex codes 1 the LED blink codes the Error Class Hex codes 2 and the Sense Key Hex codes 3 Fatal Bllnk code 2 3 Meaning Error S S S S S S 00 00 No Error S S S S S L 33 05 Append Error S S S S L S 20 05 Bad command block S S S S L L 20 05 Bad paramo block S S S L S S 00 04 Bus parity Error S S S L S L 04 02 Busy S S S L L S ...

Страница 155: ... L L 00 05 Data Transf Error L S L L S S 00 OB Selection Failure L S L L S L 00 CB Sequence Error L S L L L S 20 OB Illegal Block Size L L S S S L 04 02 Buffer Size Error L L S S L S 04 02 Rereads Outsd Limts L L S S L L 04 02 Rewrts Outsd Limts L L S L S S 04 02 Buff Err Low Nibble L L S L S L 04 02 Buff Err High Nibb L L S L L S 04 02 Unspec Fatal Error L L S L L L 04 02 Timeout Error L L L S S ...

Страница 156: ... A drive related or controller related hardware error occurred Media Not Loaded 09 The tape cartridge was removed during the execution of the command Unrecoverable Error 11 The TDC3620 40 60 Drive per formed the maximum number of retries on the block 16 for Write or 24 for Read Media Not Loaded 09 The tape cartridge was not loaded before a command was issued Un Attention 30 The tape cartridge was ...

Страница 157: ...TANDBERG DATA B 2 Appendix B This Page Intentionally Left Blank ...

Страница 158: ...of utilizing the IDC 3620 40 60 Drive is to transfer data between the Drive itself and a hard disk This could be done either directly by using the Copy command or indirectly via the Host Adapter Buffer The overall bus performance depends primarily on the hard disk interleave factor Interleave factor no of disk spindle revolu tions made to read a complete disk track Typically the inter leave factor...

Страница 159: ...ion of the written data will appear after a short delay If problems occur during writing this has to be reported when the next command is issued Buffered Mode can also be useful to systems that do not support the Deselect function It can be used to achieve early release of the SCSI bus so that it can be used for other tasks instead of waiting for the tape to complete the Write process C 2 If Strea...

Страница 160: ...ve operates in this mode and the buffer gets empty during Write the last data block will be rewritten until more data is available In this way it is possible to achieve streaming mode operation However the tape capacity the effective bus transfer rate will be reduced by a factor of 90 Kbytes sec See Section 9 3 5 Mode Select for more information C 3 How to Optimize SCSI Performance The SCSI system...

Страница 161: ...ill then take place as high speed bursts each burst containing control information or a cenain number of data blocks The amount of blocks transferred in each burst may influence the overall system performance In order to help optimizing the performance the TDC 3620 40 60 Drive has selectable bus thresholds see Mode Se lect The bus thresholds specifies the no of blocks that should be transferred in...

Страница 162: ...ed from the following figure showing the five layers PHYSICAL SIZE MAX SIZE CURRENT SIZE DYNAMIC SIZE ACTUAL SIZE Each of the five layers is divened from the layer above The result of this is that a layer cannot be larger than maximum the size of the layer above The use of each layer is as follows all figures are in number of blocks 512 bytes ttf gi This is the maximum physical buffer mem RfltENT ...

Страница 163: ...e written on the tape before at least WRITE TIlRESHOLD number of datablocks are available in the buffer During a Read command no data will be read from the tape before the buffer can accept at least READ TIiRESHOLD number of blocks With the given functionality of the buffer and the configuration variables it is possible to configure the Drive so that it will not operate at aJl For example for a Dr...

Страница 164: ...ape has not staned to empty the buffer because of the relatively long time it takes to write the Reference Track At this moment the buffer will contain 64 blocks of data There is a free space of 117 64 53 blocks Because this is less than the Bus Threshold value a new data transfer is not immediately staned After some time the tape will fetch data from the buffer When at least 11 blocks are written...

Страница 165: ...erg Data products please contact Tandberg Data AlS Oslo Norway or our local subsidiary company For addresses and telephone numbers please refer to the back of this publication _ b 1 l oI I f i J GJ O 11 1 1 _ I_ Technical Training Courses TANDBIAG DATA _ _ Tandberg Data AlS P O Box 9 Korsvoll N 0808 OSLO 8 NORWAY ...

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