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Summary of Contents for Bi-Compliant SAB850

Page 1: ...SA850 851 Bi Compliant Double Sided Diskette Storage Drive Shugart ...

Page 2: ...al Interface 4 1 Signal Interface 4 1 1 InputLines 4 1 1 1 Input Line Termination 4 1 1 2 DriveSelect1 4 4 1 1 3 Side Select 4 1 1 4 Direction Select 4 1 1 5 Step 4 1 1 6 Write Gate 4 1 1 7 Write Data 4 1 1 8 Head Load Alternate Input 4 1 1 9 In Use Alternate Input 4 1 1 10 Write Current Switch Active Read Compensation 4 1 2 Output Lines 4 1 2 1 Track 00 4 1 2 2 Index 4 1 2 3 Sector SA851 only 4 1...

Page 3: ...rnate Input Activity LED 7 7 Write Protect Optional Use 7 8 Disk Change Optional Output 7 9 Side Selection Using Direction Select 7 10 Side Selection Using Drive Select 7 11 Door Lock Latch 7 12 Two Sided Optional Output 7 13 Head Current Switch Active Read Compensation 7 13 1 Head Current Switch 7 13 2 Active Read Filter 7 14 Ready Standard Ready Modified 7 15 Head Load Latch 8 0 Operation Proced...

Page 4: ...10 Component Locations PIN 25188 22 MLC 11 PCB Component Locations PIN 25200 23 Select Drive Without Loading Head Circuit 24 Stepper Motor Enable Circuit 25 Load Head Without Selecting Drive or Enabling Stepper Circuit 26 Radial Ready Circuit 27 Radiallndex Sector Circuit 28 In Use Activity LED Circuit 29 Write Protect Circuit 30 Disk Change Timing 31 Disk Change Circuit 32 Side Selection Using Di...

Page 5: ...s track to track access time In addition Shugart s Bi Compliant read write head assembly pro vides superior compliance resulting in excellent data integrity Other valuable features include programmable door lock and write protect plus dual index sensor to dif ferentiate between single and two sided diskettes The SA850 851 will prove highly cost effective in applications such as intelligent termina...

Page 6: ... ms 15 ms 50 ms Double Density 1600 kilobytes 800 kilobytes 10 4 kilobytes 1000 kilobytes 500 kilobytes 6 66 kilobytes 500 kilobits sec 83 ms 3 ms 91 ms 15 ms 50 ms 1 2 2 FUNCTIONAL SPECIFICATIONS Single Density Double Density I otational Speed 360 rpm 360 rpm I ecording Density 3408 bpi 6816 bpi inside track Flux Density 6816 fci 6816 fci Track Density 48 tpi 48 tpi Cylinders 77 77 Tracks 154 154...

Page 7: ...24VDC 10 1 0A Max 5VDC 5 1 1A Max Mechanical Dimensions exlusive of front panel SA850R 851 R SA850 851 Height 4 62 in 117 mm 4 62 in 117 mm Width 8 55 in 217 mm 9 50 in 241 mm Depth 14 25 in 362 mm 14 25 in 362 mm Heat Dissipation Typical Maximum BTU Hr 200 245 Watts 60 72 1 2 4 RELIABILITY SPECIFICATIONS MTBF MTTR Component Life Error Rates Soft Read Errors Hard Read Errors Seek Errors Media Life...

Page 8: ...id Driver 4 Read Write Amplifier and Transition Detector 5 Data Clock Separation Circuits SA851 only 6 Write Protect 7 Drive Ready Detector Circuit 8 Drive Select Circuits 9 Side Select Circuit 10 In Use and Door Lock Circuits 11 Write Current Switching Read Compensation 2 3 DRIVE MECHANISM The Diskette drive motor rotates the spindle at 360 rpm through a belt drive system 50 or 60 Hz power is ac ...

Page 9: ...ETECTOR INDEX LED HEAD 1 HEAD 0 READ LOGIC WRITE LOGIC CONTROL LOGIC READ DATA SEP DATA FM SEP CLOCK FM WRITE DATA WRITE GATE WRITE PROTECT SIDE SELECT IN USE LED HEAD LOAD OPTIONAl STEP DIRECTION SIDE SELECT OPTIONAl DRIVE SELECT TRACK 00 INDEX READY SECTOR 851 ALTERNATE I O 3 LINES TWO SIDED OPTIONAl DISK CHANGE LD FIGURE 1 SA850 851 FUNCTIONAL DIAGRAM ...

Page 10: ...terchangeability The diskette is held in a plane perpendicular to the read write heads by a platen located on the base casting This precise registration assures perfect compliance with the read write heads The flexure mounted head is loaded against its rigidly mounted counterpart via the head load solenoid The read write heads are in clirect contact with the diskette The head surface has been desi...

Page 11: ...tput lines light the Activity LED on the front of the drive and lock the door Optional modes of drive selection are discussed in Section 7 3 3 TRACK ACCESSING Seeking the read write head from one track to another is accomplished by a Activating Drive Select line b Selecting desired direction utilizing Direction Select line c Write Gate being inactive d PUlsing the Step line Multiple track accessin...

Page 12: ...DC POWER DRIVE SELECT ss r 55 OUT DIRECTION SELECT STEP IN J FIGURE 2 TRACK ACCESS TIMING 8 j 3 ms MIN ...

Page 13: ...t changes state before a read or write operation can be initiated Figure 3 shows the use of Side Select prior to a read operation Two jumper selectable Side Select options are also available Either of these can be implemented to make use of existing controller and cable harness design These options are described fully in Section 7 ss DC POWER DR VE SELECT I S I j STEP SS 1 l J 90 ms 1 100 8 MIN SI...

Page 14: ...RE 4 FM MFM AND M2FM CODE COMPARISONS RE A D DATA I A B SEP DATA 851 __ I __ I ONLY 4 00p s NOM 200 50ns LJ 2 00p s NOM u 2 00p s NOM u A LEADING EDGE OF BIT MAY BE 400ns FROM ITS NOMINAL POSITION B LEADING EDGE OF BIT MAY BE 200ns FROM ITS NOMINAL POSITION FIGURE 5 READ SIGNAL TIMING FM ENCODING 10 ...

Page 15: ...he current bit cell if either the preceding bit cell or the current bit cell contains a data bit See Figure 4 b M2FM The clock bit is omitted from the current bit cell if the preceding bit cell contained any bit clock or data or if the current bit cell contains a data bit See Figure 4 In all three of these encoding schemes clock bits are written at the start of their respective bit cells and data ...

Page 16: ... are required in order to guarantee that the read write head position has stabilized prior to writing Write data encoding can be FM MFM or M2FM If either double frequency encoding scheme is used MFM or M2FM the write data should be precompensated to counter the effects of bit shift The amount and direc tion of compensation required for any given bit in the data stream depends on the pattern it for...

Page 17: ...I r 18 MS MIN WRITE GATE IL _ I 1 4 00 8 MAX U U STEP WRITE DATA 2 SECONDS IF AC AND DC POWER ARE APPLIED AT SAME TIME FIGURE 6 WRITE INITIATE TIMING WRITE DATA FM 1 150n8 MIN 1100ns MAX I 4 00 s 20 ns l 2 00 s I 10ns FIGURE 7 WRITE DATA TIMING FM ENCODING 13 ...

Page 18: ...STEP lJnj J p sll 3 ms MIN l I I I I rc I 18mS WRITE GATE 1 I I 9LsM11 0 MIN I H I I N O T E 1 I 4Jts MAX I I t ru I 18msMIN 50 SMIN I FNOTE1 4 n P r 90 ms MAX 2 SECONDS IF AC AND DC POWER ARE APPLIED AT SAME TIME WHEN CHANGING DIRECTION ON THE HEAD A 15 MS DELAY MUST BE INTRODUCED NOTE 1 50 ms minimum delay must be introduced after Drive Select to allow for proper head load settling If stepper po...

Page 19: ...T 30 29 31 32 DIRECTION SEU CT SIDE SELECT OPT 14 33 STEP 36 35 WRITE DATA 38 37 WRITE GATE 40 39 TRACK 00 42 41 WRITE PROTECT 44 43 READ DATA 45 46 SEP DATA 851 ONLY 48 47 SEP CLOCK 851 ONLYl 50 49 5 VDC 5 J5 6 I L DCGND 24 VDC 1 2 X 24 V RETURN J4 ACINPUT 1 FRAME GROUND ACINPUT AC GND r fT1 FRAME GND TWISTED PAIR These lines are alternate input output lines and they are enabled by jumper plugs R...

Page 20: ...de signals to the host output via interface connector P1 J1 4 1 1 INPUT LINES There are thirteen 13 signal input lines ten 10 are standard and three 3 are user installable options reference section 7 TIle input signals are of two types those intended to be mUltiplexed in a multiple drive system and those which will perform the multiplexing The input signals to be mUltiplexed are 1 Direction Select...

Page 21: ...teface 2 External termination may be used provided the terminator is beyond the last drive Each of the five lines should be terminated by using a 150 ohm 1J t watt resistor pulled up to 5VDC The same removable resistor pack is also provided for terminating the optional input lines 4 1 1 2 DRIVE SELECT 1 4 Drive Select when activated to a logical zero level activates the multiplexed I O lines and l...

Page 22: ...OTE A 15ms delay must be introduced when changing direction i e the last step in pulse to first step out pulse or vice versa 4 1 1 5 STEP This interface line is a control signal which causes the read write heads to move with the direction of motion as defined by the Direction Select line The access motion is initiated on each logical zero to logical one transition or the trailing edge of the signa...

Page 23: ...e 166 67 ms to indicate the beginning of the track Normally this signal is a logical one and makes the transition to the logical zero level for a period of 1 8 ms 0 4 ms on SA851 once each revolution The timing for this signal is shown in Figure 11 To correctly detect Index at the control unit Index should be false at Drive Select time that is the controller should see the transition from false to...

Page 24: ...Normally this signal is a logical one level and becomes a logical zero level for the active state Reference Figure 5 for the timing 4 1 2 7 SEP CLOCK SA851 only This interface line furnishes the clock bits as separated from the raw data by use of the internal data separator Normally this signal is a logical one level and becomes a logical zero level for the active tate Reference Figure 5 for the t...

Page 25: ...ame Gnd Frame Gnd 3 85 127 V Rtn 170 253 V Rtn 85 127 V Rtn 170 253 V Rtn MAX 0 35 Amps 0 25 Amps 0 35 Amps 0 25 Amps CURRENT FREQ 0 5 Hz 0 5 Hz TOLERANCE TABLE 1 4 2 2 DC POWER DC power to the drive is via connector P5 J5 located on the non component side of the PCB near the P4 con nector The two DC voltages and their specifications along with their P5 J5 pin designators are outlined in Table 2 P...

Page 26: ...ons for this connector are shown in Figure 13 The pins are numbered 1 through 50 with the even numbered pins on the component side of the PCB and the odd numbered pins on the non component side Pin 2 is located on the end of the PCB connec tor closest to the AC motor capacitor and is labeled 2 A key slot is provided between pins 4 and 6 for op tional connector keying The recommended connectors for...

Page 27: ...drive PCB from non component side 5 3 J4 P4 CONNECTOR The AC power connector J4 is mounted on the AC motor capacitor bracket and is located just below the capacitor J4 connector is a 3 pin connector AMP PIN 1 480701 0 with pins PIN 350687 1 2 EA and 350654 1 1 EA The recommended mating connector P4 is AMP PIN 1 480700 0 utilizing pins 350550 1 Figure 15 illustrates J4 connector as seen from the re...

Page 28: ...RECOMMENDATIONS The SA850 851 is capable of being mounted in one of the following positions refer to Figure 17 1 Vertical Door opening to the left or right 2 Horizontal Door opening up PCB down 3 Upright To mount the drive in this position remove the spring hook attached to the eject mechanism and attach the eject spring to the post the spring hook was attached to DOOR OK B NOT RECOMMENDED FIGURE ...

Page 29: ...ons are in Inches OJ m m 4 0 02 40 02 MOUNTING 12XI I mLlDE irEtl Decorative Cover Dimensions Cover Size Dim A Dim B DimC 4 5 8 x 10 1 2 10 50 240 4 62 5 1 4 x 10 10 00 240 5 25 5 1 4 x 11 11 00 740 5 25 Tolerance 03 030 03 1 8 32 7X 31 MIN FULL THREAD FUNCTIONAL II FACEPLATE 0 l I 1lJT I 0 I L I r nrl LJ J Jl It 0 3 0 3 0 0 l q 0 q j 798 020 4 0 02 12XI _I I 12XI C5 c D m J ex CJ1 0 03 CJ1 0 en m...

Page 30: ...ate thickness 4 Cosmetic front cover width 8 Cosmetic front cover color comes only in tan 4 02 F 1 00 01 855 03 0 0 I l 1 54 x RE n 0 U l T N I q N C I 1 00 0 I LO 1 eti It ll1V 1 r 111 OJ tt fffS E74 06 dJ 5 8 55 02 1 1 mrn co U l C N 8 68 02 1 450 02 1 4 62 _ 02 4 62 03 2 49 02 I I I I I I X x q I 1 n 8 0 cO U l X N C I I LL ______ x N o t o CX J 1 FIGURE 19 SA850 851 R DIMENSIONS 26 ...

Page 31: ... ordered with one of the following decorative face plates SIZE COLOR 4 5 8 x 10 1 2 Tan 4518 x 10112 White 5 1 4 x 10 Tan 5 1 4 x 10 White 5 1 4 x 11 Tan 5 1 4 x 11 White II R Series 4 5 8 x 8 11 16 Tan If another color is required to match the system s color scheme the face plate may be painted The follow ing information should be utilized to avoid potential problems in the painting process 1 The...

Page 32: ...lug Shugart PIN 15648 or AMP PIN 53013 2 This section will discuss a few examples of modifications and how to install them The examples are 1 Select drive without loading head or enabling stepper 2 Select drive and enable stepper without loading head 3 Load head without selecting drive or enabling stepper 4 Radial Ready 5 Radial Index Sector 6 In Use Activity LED optional input 7 Write Protect opt...

Page 33: ...ide Select Input Plugged S3 Side Select Option Using Drive Select X TS FS Data Separation Option Select TS FS Plugged IW Write Current Switch Plugged RS Ready Standard Plugged RM Ready Modified X HLL Head Load Latch X IT In Use Terminator Plugged HI Head Load or In Use to the In Use Circuit X F Remove for MFM encodinq install for M2FM X AF Install for FM or MFM encoding Pluqged NF Install for M2FM...

Page 34: ...Ie ROI W TV _ _ 2_ _ J r IT l i C8 I QJD TV en o J5 R21 R28 tnO 3D SO 10 20 R21 R22 R2J IVI ClJ _ _ q0 l 8 o CfJ 80 F cIEJ CO 2E 3 SE 8E QJ 7E Q o Ecs I ITO D o o C 3f 7f 0 QrJ en ef IT D 00 JJ 1 11 qf 2 CfJ JJ co i N D 3 S iOCfJ DS4 48 I Sf FIGURE 21 MLC 10 COMPONENT LOCATIONS PIN 25188 30 ...

Page 35: ...114 0 II It IC E I J 9 I I 2C I 21 OOD 000000 o fer o 1 C r 7 1 20 40 30 t d 35 1121 112t1 IDD O mo o 4 IE liB C21 R60 D Ow 2 D I E o 3f I Bf 00 I I I I I I L J i DS1 I 4r 18 DS2 J n l i N Jl 28 DS3 38 0 0 DS4 48 I FIGURE 22 MLC 11 PCB COMPONENT LOCATIONS PIN 25200 31 ...

Page 36: ...n on a standard drive the following traces should be deleted or added 1 Cut trace X 2 Jumper trace C 7 2 SELECT DRIVE AND ENABLE STEPPER WITHOUT LOADING HEADS This option is useful to the user who wishes to select a drive and perform a seek operation without the heads being loaded or with door open An example use of this option is that at power on time an automatic recalibrate reverse seek to trac...

Page 37: ...G STEPPER This option is useful in disk to disk copy operations It allows the user to keep the heads loaded on all drives thereby eliminating the 50 ms head load time The heads are kept loaded on each drive via an Alternate I O pin Each drive may have its own Head Load line Radial or Simplexed or they may share the same line Multiplexed When the drive is selected an 15 rris delay must be introduce...

Page 38: ...EAD LCAD B DD A x j _ DRIVE SELECT II j C 4 4 M _ L 6 6 l r IIpp 8 I M II I 18 18 h M __ ll 5 vu DOOR CLOSED HEAD LOAD ALTERNATE 1 0 PINS 32 STANDARD TRACE DRIVE SELECT 4 30 III DELETED TRACE DRIVE SELECT 3 28 ADDED OR JUMPERED TRACE DRIVE SELECT 2 26 DRIVE SELECT 1 If the Head Load line is multiplexed termination pack 5E must be removed from each drive except the last one on the line FIGURE 25 LO...

Page 39: ...ould be deleted or added 1 Cut trace RR 2 Cut trace R 3 Add a wire from pad R to one of the Alternate I O pins One of the drives on the interface may use pin 22 as its Ready line therefore steps 2 and 3 may be eliminated on this drive All the other drives on the interface must have their own Ready line therefore step 2 and 3 must be incorporated Figure 26 illustrates the circuitry 4 RR DRIVE SELEC...

Page 40: ...ire from trace I to one of the Alternate I O pins 5 Add a wire from trace S to one of the Alternate I O pins One of the drives on the interface may use pin 20 Index and pin 24 Sector as its Index and Sector lines therefore steps 2 5 may be eliminated for this drive All other drives on the interface must have their own In dex and Sector lines therefore steps 2 5 must be incorporated Figure 27 illus...

Page 41: ...EAD LOAD 1 5V DOOR LOCK WRITE GATE FIGURE 28 IN USE ACTIVITY LED CIRCUIT 7 7 WRITE PROTECT OPTIONAL USE As shipped from the factory the optional Write Protect feature will internally inhibit writing when a Write Pro tected Diskette is installed With this option installed a Write Protected Diskette will not inhibit writing but it will be reported to the interface This option may be useful in identi...

Page 42: ...cted the drive has gone from a r eady to a Not Ready Door Open condition This line is reset on the true to false transition of Drive Select if the drive has gone Ready Timing of this line is illustrated in Figure 30 The circuitry is illustrated in Figure 31 DRV SEL READY DISK CHG 5V s r S S I Ss r S INTERNAL s J ENABLE FIGURE 30 DISK CHANGE TIMING READY o 0 CO 12 DISK CHG DRV SEL FIGURE 31 DISK CH...

Page 43: ...ect line controls the direction of head motion during stepping operations and controls side head selection during read write operations To implement this option simply move jumper S2 to location S1 Figure 32 illustrates the circuitry DRIVE SELECT S2 SIDE SELECT S1 SIDE 0 CT SIDE 1 CT DIRECTION SELECT SiDE SELECT FIGURE 32 SIDE SELECTION USING DIRECTION SELECT 39 ...

Page 44: ...ers installed at DS1 and 28 while the second drive has jumpers at DS3 and 48 With this jumper configuration installed the four Drive Select lines have the following side selection functions 1 Drive Select 1 selects side 0 of first drive 2 Drive Select 2 selects side 1 of first drive 3 Drive Select 3 selects side 0 of second drive 4 Drive Select 4 selects side 1 of second drive Figure 33 illustrate...

Page 45: ...tive a latch will be set which holds the door lock circuit active To unlock the door Drive Select is again activated while In Use is inactive Figure 34 illustrates the circuitry for this option 5V I N USE 1 o _ IC TO IN USE LED DRIVER TO DOOR LOCK DRIVER DRIVE SELECTINT DL FIGURE 34 DOOR LOCK LATCH CONTROL 7 12 TWO SIDED OPTIONAL OUTPUT This signal indicates whether a Two Sided True Output or a Si...

Page 46: ...ated to a logical zero level the read signal is passed through an active filter network for reading tracks 60 through 76 Performance will improve when reading a diskette that has been recorded without write precompensation To control the active read filter from the interface short trace IW to connect to the interface remove jumpers AF and NF When the interface is activated to a logical zero level ...

Page 47: ...erto figure 36 If In Use is to be used jumper pin D to pin HI refer to figure 37 In both cases trace A on shunt 4F must be cut To load and latch the heads the user must activate either the Head Load or In Use lines and select the drive When the drive is deselected the heads will stay loaded and the door locked To unload the heads the Head Load or In Use line must be inactive when the drive is sele...

Page 48: ... 5V tiT TO IN LED USE DRIVER TO DOOR LOCK DRIVER 16 D IN USE HI A B FIGURE 37 HEAD LOAD LATCH USING IN USE 44 ...

Page 49: ...r on and drive spindle rotating When removed from the drive the diskette is stored in an envelope To protect the diskette the same care and handling procedures specified for computer magnetic tape apply These precautionary procedures are as follows 1 Return the diskette to its storage envelope whenever it is removed from drive 2 Keep diskettes away from magnetic fields and from ferromagnetic mater...

Page 50: ...ar of the slot The Diskette can then be write protected by removing the tab See Figure 39 8 3 WRITE PROTECT IBM DISKETTES IBM Diskettes are not manufactured with a write protect slot punched out as are the Shugart Diskettes To Write Protect one of these diskettes a slot must be punched out as specified in Figure 40 The operation of the write protect is that which is outlined in paragraph 8 2 FOLD ...

Page 51: ...iper 2 Random electrical noise which usually lasts for a few microseconds 3 Small defects in the written data and or track not detected during the write operation which may cause a soft error during a read The following procedures are recommended to recover from the above mentioned soft errors 1 Reread the track ten 10 times or until such time as the data is recovered 2 If data is not recovered af...

Page 52: ...LATCH STOP SHIPPING DISK FIGURE 41 PACKAGE ASSEMBLY 48 ...

Page 53: ...MINIMUM LOAD MAXIMUM LOAD FIGURE 42 PALLET LOADING 49 ...

Page 54: ...S Size Color Part Numbers 4 5 8 x 10 1 2 Tan 50264 4 5 8 x 10 1 2 White 50263 5 1 4 x 10 Tan 50261 5 1 4 x 10 White 50260 5 1 4 x 11 Tan 50258 5 1 4 x 11 White 50257 Rack Mount 4 5 8 x 8 11 16 Tan 50675 Primary Voltage Part Numbers and Motor Motor Frequency ASM Pulley Belt 115 VAC 60 Hz 50747 50358 50356 115 VAC 50 Hz 50747 50357 50355 230 VAC 60 Hz 50748 50358 50356 230 VAC 50 Hz 50748 50357 5035...

Page 55: ...39018 0 12 80 Shugart Copyright 1977 475 Oakmead Parkway Sunnyvale California 94086 Telephone 408 733 0100 TWX 910 339 9355 SHUGART SUVL PRINTED IN U S A ...

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