Remex RFD4000-A User manual

TECHNICAL MANUAL
DISKETTE DRIVE
MODELS: RFD4000-A RFD2000-A
RFD4001-A RFD2001-A
IMPORTANT INFORMATION
Changes to the equipment which are made between manual
printings are listed in an addendum at the rear of the manual.
As aconvenience, alist of change pages is given as the last
page in the manual. It is recommended that each of these
pages be marked "Refer to Addendum" so that these changes
can be identified.
EX-CELL-0 CORPORATION
Remex
1733 Alton St •P.O. Box C-19533 •Irvine, CA 92713
112670-103A

Copyright °1979 by REMEX, AUnit of Ex-Cell-0
Corporation. Printed in the United States of America.
All rights reserved. This: book or parts thereof may not
be reproduced in any form without permission of the
publishers
.

»A»aAN8$
The following section is part of the Standard Terms and Conditions and covers only the
Warranty. The reader should refer to the complete Standard Terms and Conditions for
the entire sales agreement.
The Seller warrants to the original Buyer only, that the Product, except as to software
and firmware, is free from defects in workmanship and material under normal use and
service. The Seller's obligation under this warranty shall be limited to furnishing a
replacement for, or at the Seller's option repairing any Product or any part or parts
thereof, which provedefectivewithin 90 days* from the date of shipment by the Seller,
provided such Product or such part or parts are returned to the Seller transportation
prepaid.
The Seller warrants, for aperiod of thirty (30) days from the date of shipment by the
Seller to the original Buyer only, that the software and firmware Products are free from
defects in workmanship and material. Seller's obligation under this warranty shall be
limited to correcting any of said defects or replacing the software or firmware. Said
warranty shall be void and of no effect whatsoever in the event that changes or addi-
tions have been made to the software or firmware (or in the event that the software or
firmware product has been adapted by the Buyer) to serve afunction not within the
system specifications of the Seller.
All replacement Products or parts thereof furnished under this warranty will be invoiced
in the usual manner and adjustments will be made after the Product or part thereof
claimed to be defective has been returned to, and inspected at, the Seller's plant.
Replacements shall be furnished under this warranty F.O.B. Buyer's plant, and the
Seller shall not be responsible for installation costs, (For all international transac-
tions, replacement shall be furnished F.O.B. Port of Entry and Buyer is responsible for
all customs and brokerage fees.) The Buyer shall be liable for all freight inspection
and handling costs if such Product or such part or parts do not prove to be defective.
In no event will any claim for labor in removing or replacing adefective Product or
part for incidental or consequential damages be allowed. No warranty is made as to
any Product or part which has not been installed, operated, or maintained in accord-
ance with Seller's instructions or the instructions contained in its operations or main-
tenance manuals, when furnished by the Seller, or which has been subject to misuse,
abuse, accident, or alteration or to improper or negligent use, maintenance, storage,
transportation or handling.
This warranty is in lieu of all other warranties expresses or implied, including any
warranty of merchantability or fitness for aparticular purpose, and the Seller neither
assumes, nor authorizes any person or firm to assume for it, any other or further obliga-
tion or liability in connection with the sales, installation or use of any product.
UNDER NO CIRCUMSTANCES SHALL SELLER OR ANY AFFILIATE OF SELLER HAVE
ANY LIABILITY WHATSOEVER FOR LOSS OF USE OR FOR ANY INDIRECT, INCI-
DENTAL OR CONSEQUENTIAL DAMAGES.
*AII paper tape products are covered under this warranty for aperiod of one year,
excepting punch mechanisms, lamps and fuses which are warranted for aperiod of 90
days. Flexible disk drives are warranted for aperiod of 180 days.

FOR YOUR SAFETY
Before undertaking any maintenance procedure, whether it be aspecific trouble-
shooting or maintenance procedure described herein or an exploratory procedure
aimed at determining whether there has been amalfunction, read the applicable
section of this manual and note carefully the |WAKiHIfM^j JQncj
contained therein.
CAUTION
The equipment described in this manual contains voltages hazardous to human life
and safety and may contain mechanical components capable of inflicting personal
injury. The cautionary and warning notes are included in this manual to alert oper-
ator and maintenance personnel to the electrical and mechanical hazards and thus
prevent personal injury and damage to equipment.

Section
I
1. 1
1. 1. 1
1. 1. 2
1. 1. 3
1. 1. 4
1. 2
1. 3
1. 4
1. 5
1. 6
1..7
1..7. 1
1.,7. 2
1..7. 3
1.,7. 4
1,.7. 5
1,.8
II
1,.1
2.2
1,.3
2.3..1
2 .3..2
2.4
2.5
2.5,,1
2.5,.2
2.5,.3
TABLE OF CONTENTS
Title Page
GENERAL DESCRIPTION 1-1
EQUIPMENT DESCRIPTION 1-1
RFD4000 FEATURES 1-2
RFD4001 FEATURES 1-2
OPTIONS, FACTORY INSTALLED 1-2
OPTIONS, CUSTOMER INSTALLED 1-3
MAINTENANCE EQUIPMENT REQUIRED BUT NOT SUPPLIED. ... 1-3
EQUIPMENT WARRANTY 1-3
SPECIFICATIONS 1-3
DISKETTE 1-5
RECORDING FORMAT 1-5
MAINTENANCE AND RELIABILITY 1-5
DESIGN LIFE 1-5
RECOVERABLE READ ERROR 1-5
NON-RECOVERABLE READ ERROR RATE 1-5
ACCESS POSITIONING ERROR RATE 1-11
INTERCHANGEABILITY 1-11
MODEL NUMBER DESIGNATION 1-11
INSTALLATION AND INTERFACE 2-1
UNPACKING 2-1
MOUNTING 2-1
INITIAL ADJUSTMENTS 2-1
LINE TERMINATOR 2-1
DRIVE SELECT JUMPERS 2-2
POWER AND SYSTEM CONNECTIONS 2-2
DOUBLE DENSITY DESIGN CONSIDERATIONS 2-5
DOUBLE FREQUENCY AND MFM ENCODING COMPARED .... 2-5
IMPLEMENTATION OF MFM 2-6
M2MF FORMAT DESCRIPTION 2-9
112670-103A

TABLE OF CONTENTS
(CONTINUED)
Title Page
OPERATION 3-1
INPUT-OUTPUT SIGNALS 3-1
OPERATOR CONTROLS 3-1
LOADING AND OPERATING INSTRUCTIONS 3-1
POWER UP MODE 3-1
DISKETTE HANDLING 3-4
DISKETTE LOADING/UNLOADING 3-5
DRIVE SELECTION 3-6
TRACK POSITIONING 3-6
SIDE SELECTION 3-6
READ OPERATION 3-6
WRITE OPERATION 3-7
COMPOSITE SEQUENCE 3-8
ERROR DETECTION AND CORRECTION 3-8
Write Error 3-8
Read Error 3-10
Seek Errors .. . 3-10
RFD4001 FEATURES 3-11
DATA SEPARATOR 3-11
SECTOR OUTPUT 3-11
FACTORY INSTALLED OPTIONS. .3-11
CUSTOMER INSTALLED OPTIONS •3-13
SIDE SELECTION UTILIZING DRIVE SELECT
LINES (RFD4000 AND RFD4001 ONLY) 3-13
RADIAL READY 3-13
RADIAL INDEX AND SECTOR .3-17
TWO-SIDED STATUS OUTPUT (RFD4000 AND
RFD4001 ONLY) 3-17
INDEX OUTPUT 3-17
SECTOR OUTPUT 3-17
vi 112670-103A
Section
III
3. 1
3. 2
3. 3
3. 3. 1
3. 3. 2
3. 3. 3
3. 3. 4
3. 3. 5
3. 3. 6
3. 3. 7
3. 3. 8
3. 3. 9
3.,3.,10
3.
3.
3,
.3.
.3.
.3.
,10.1
,10.2
,10.3
3,.4
3,.4.,1
3.4.,2
3..5
3.6
3.6 .1
3.6 .2
3.6 .3
3.6 .4
3.6 .5
3.6 .6

TABLE OF CONTENTS
(CONTINUED)
Section Title Page
3.6.7 DISK CHANGE OPTION 3-18
3.6.8 DRIVE SELECT WITHOUT LOADING HEADS OR ENABLING
STEPPER MOTOR 3-18
3.6.9 DRIVE SELECT AND STEP MOTOR ENABLE WITHOUT
LOADING HEAD 3-18
3.6.10 HEAD LOAD WITHOUT SELECTING DRIVE OR ENABLING
STEP MOTOR 3-18
3.6.11 IN USE ALTERNATE INPUT 3-19
3.6.12 SIDE SELECTION USING DIRECTION SELECT 3-19
3.6.13 DOOR LOCK LATCH 3-19
3.6.14 WRITE PROTECT OPTIONAL USE 3-19
3.6.15 -5 VOLT OPTION 3-20
3.6.16 DATA SEPARATION OPTION SELECT (MODEL RFD4001 ONLY) .3-20
IV THEORY OF OPERATION 4-1
4.1 BLOCK DIAGRAM DESCRIPTION 4-1
4.1.1 DISKETTE DRIVE MECHANISM 4-1
4.1.2 HEAD POSITIONING MECHANISM 4-1
4.1.3 READ/WRITE HEAD 4-1
4.1.4 DRIVE ELECTRONICS 4-3
4.1.5 DIGNAL MNEMONICS 4-4
4.2 FUNCTIONAL DESCRIPTION 4-4
4.2.1 READ CIRCUITS AND DATA SEPARATOR (RFD4001
AND RFD2001) 4-4
4.2.2 WRITE CIRCUITS <4-6
4.2.3 ERASE CIRCUITS 4-8
4.2.4 STEP MOTOR DRIVE CIRCUITS 4-8
4.2.5 INDEX/SECTOR CIRCUITS 4-10
4.2.6 WRITE PROTECT CIRCUIT 4-11
4.2.7 DISK CHANGE CIRCUIT 4-11
4.2.8 TWO-SIDED CIRCUITRY (RFD400X ONLY) 4-12
4.2.9 DRIVE SELECT LOGIC •4-12
11267O-103A vii

TABLE OF CONTENTS
(CONTINUED)
Title Page
SIDE SELECT LOGIC (RFD4000 AND RFD4001 ONLY) .... 4-12
POWER UP RESET 4-13
DOOR CLOSED CIRCUIT 4-13
CUSTOMER INSTALLABLE OPTIONS 4-13
Side Selection Utilizing Drive
Select Lines 4-13
Radial Ready 4-13
Radial Index and Sector 4-14
Two Sided Status Output 4-14
Disk Change Option •.4-14
Drive Select Without Loading Heads or
Enabling Stepper Motor 4-14
Drive Select and Motor Enable Without
Loading Head 4-16
Head Load Without Selecting Drive or
Enabling Step Motor 4-17
In Use Alternate Input 4-17
Side Selection Using Direction Select
(RFD400X ONLY) 4-18
Door Lock Latch 4-18
Write Protect Optional Use 4-19
-5 Volt Option 4-19
Data Separation Option Select (Models
RFD4001 and RFD2001 Only). 4-19
MAINTENANCE 5-1
GENERAL 5-1
MAINTENANCE PROCEDURES 5-1
READ/WRITE HEAD CLEANING 5-2
Read/Write Head Cleaning, RFD400X Only 5-2
Read/Write Head Cleaning, RFD200X Only ...... 5-2
TROUBLESHOOTING 5-4
ELECTRICAL ADJUSTMENTS 5-8
TRACK ALIGNMENT 5-8
TRACK 00 SWITCH AND MECHANICAL STOP ADJUSTMENT ... 5-9
INDEX ALIGNMENT 5-10
WRITE PROTECT ADJUSTMENT 5-11
viii 112670-103A
Section
4..2.,10
4.,2.,11
4..2..12
4..2..13
4..2,.13,.1
4,
4,
4.
4,
4,
.2,
.2,
.2,
.2,
.2,
.13,
.13,
.13,
.13,
.13,
.2
.3
.4
.5
.6
4,.2,.13 .7
4,.2,.13 .8
4,
4.
.2,
.2,
.13
.13
.9
.10
4
4,
4
4
.2
.2
.2
.2
.13
.13
.13
.13
.11
.12
.13
.14
V
5.1
5.2
5.2 .1
5
5
.2
.2
.1.:
.1.;
L
I
5.2 .2
5.3
5.3 .1
5.3 .2
5.3 .3
5.3 .4

TABLE OF CONTENTS
Section
5.3.5
5.3.6
5.4
5.4.1
5.4.2
5.4.3
VI
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.10
6.11
6.12
VII
7.1
7.2
7.3
VIII
8.1
Title Page
R16 CROSSOVER DETECTOR INPUT DC BALANCE ADJUSTMENT. .5-12
R27-3/4 CELL ONE-SHOT ADJUSTMENT
(RFD4001 AND RFD2001 ONLY) 5-12
MECHANICAL ADJUSTMENT 5-13
LATCH PLATE/CARRIER ADJUSTMENT 5-13
DISKETTE LOAD ARM ADJUSTMENT 5-13
HEAD PAD CARTRIDGE ASSEMBLY REPLACEMENT
(RFD200X ONLY) 5-15
PARTS REPLACEMENT 6_1 .
GENERAL 6_1
PRINTED CIRCUIT CARD REPLACEMENT 6-2
MOTOR DRIVE BELT REPLACEMENT 6~2
DRIVE MOTOR ASSEMBLY REPLACEMENT 6-2
HUB PULLEY REPLACEMENT 6-3
INDEX L.E.D. ASSEMBLY REPLACEMENT 6-3
TRACK 00 OPTICAL SWITCH REPLACEMENT 6-3
EXPANDING CLUTCH ASSEMBLY REMOVAL 6-4
CARRIER ASSEMBLY REPLACEMENT 6-4
SINGLE-SIDED and TWO-SIDED INDEX SENSOR ASSEMBLIES
REPLACEMENT 6-5
DRIVE HUB REPLACEMENT 6-5
HEAD LOAD SOLENOID REPLACEMENT 6-6
PARTS LIST 7_1
GENERAL 7_1
OPTIONAL KIT OF PARTS 7_1
RECOMMENDED SPARE PARTS 7_1
SCHEMATIC DRAWINGS 8_1
GENERAL 8_1
112670-103A ix

LIST OF ILLUSTRATIONS
Figure Title Page
1-1 RFD4000 Diskette Drive 1-1
1-2 Installation Drawing, Model RFD4000 and RFD4001 1-6
1-3 Storage Element Physical Dimensions 1-7
1-4 IBM Track Format I-8
1-5 Recording Format Using Index Recording 1-9
1-6 ARecording Format for MFM Encoding .1-9
1-7 32-Sector Format 1-1°
1-8 Model Number Designation 1-13/1-14
2-1 Interface Signal Connections 2-3
2-2 Interface Signal and Connector Locations 2-4
2-3 Recommended Interface Circuits 2-4
2-4 Double Frequency Encoding 2-5
2-5 MFM Encoding 2-6
2-6 Basic Components of Double Density System 2-7
2-7 Expected Bit Shift on Read Back Data 2-8
2-8 Precompensated Write Data 2-8
2-9 Data Recovery Timing 2-9
2-10 M2FM Encoding 2-10
3-1 Power Up and Seek Sequence 3-4
3-2 Diskette Insertion 3-5
3-3 Read Sequence Operation 3-7
3-4 Write Sequence 3-8
3-5 General Read and Write Sequences 3-9
3-6 Data Separator Timing 3-12
3-7 32-Sector/lndex Timing •3-12
3-8 Trace and Jumper Locations 3-14
3-9 Trace and Jumper Locations 3-15
4-1 Block Diagram for the RFD4000 and RFD4001 4-2
4-2 Read/Write/Erase Block Diagram •4-5
4-3 Read Circuit and Data Separator Timing Diagram 4-7
4-4 Stepper Motor Energizing Sequence 4-9
4-5 Timing Diagram, Index and Sector Circuits 4-11
4-6 Radial Ready Circuit 4-14
4-7 Radial Index/Sector Circuits 4-15
4-8 Drive Select Without Loading Heads or Enabling
Stepper Motor 4-15
4-9 Drive Select and Motor Enable Without Loading Head 4-16
4-10 Head Load Without Selecting Drive or Enabling
Step Motor 4-17
4-11 Side Selection Using Direction Select 4-18
4-12 Write Protect Optional Use 4-19
x11267O-103A