Text preview for : PED226a_606_Magnetic_Tape_Transport_OEM_Reference_Manual.pdf part of cdc PED226a 606 Magnetic Tape Transport OEM Reference Manual . Rare and Ancient Equipment cdc magtape PED226a_606_Magnetic_Tape_Transport_OEM_Reference_Manual.pdf
Back to : PED226a_606_Magnetic_Tape | Home
C-ONTROL DATA
606 MAGNETIC
TAPE TRANSPORT
OEM REFERENCE MANUAL
CONTROL DATA
606 MAGNETIC
TAPE TRANSPORT
OEM REFERENCE MANUAL
PED 226a
CONTENTS
Chapter 1 - Description
Physical Description 1-1
Functional Description 1-3
Tape Format 1-3
Reflective Spots 1-4
File Protection Rings 1-5
Principles of Operation 1-6
Chapter 2 - Operation
General Operating Instructions 2-1
Application of Power 2-1
Tape Load Procedure 2-2
Tape Unload Procedure 2-3
Manual Operation 2-4
Special Instructions 2-6
Chapter 3 - Interface Considerations
Introduction i
Read Control 3-1
Select Read Circuit 3-5
Read Data Circuits 3-6
Select Density Circuit 3-8
Read Gate Circuit 3-10
File Mark Stop Circuit 3-13
Write Control 3-17
Write Enable Circuit 3-17
Write Data Circuit 3-19
Motion Control Circuit 3-20
Servo Drive Control 3-22
Photosense Circuit 3-23
Oscillator Circuit 3-25
Tachometer Circuit 3-25
iii
CONTENTS (CONT'D)
Chapter 3 - (Cont'd)
Local Control 3-27
Sense Circuits 3-28
Rewind 3-32
Rewind Unload 3-35
Move to Load Point Circuit 3-37
Load Tape 3-38
Local Control Flow Charts and Tables 3-41
Appendix Section
Appendix A Theory of Control Data Logic
Appendix B Special Purpos e Circuits
iv
FIGURES
Chapter 1 - Description
1-1 Tape Transport, Front and Rear View 1-2
1-2 Bit Assignments on Tape 1-3
1-3 Physical Layout of Tape 1-5
1-4 File Protection Ring 1-5
1-5 Tape Path Through 606 Tape Unit 1-6
Chapter 2 - Operation
2-1 Tape Load and Unload Mechanics 2-3
2-2 Operator Control Panel 2-4
Chapter 3 - Interface Considerations
3-1 Read Control Circuits 3-1
3-2 Block Diagram 3-4
3-3 Select Read Circuit 3-5
3-4 Typical Read Data Circuit 3-7
3-5 Select Density Circuit 3-9
3-6 Read Gate Circuit 3-11
3-7 Read Sequence 3-11
3-8 File Mark Stop Circuit 3-13
3-9 Operation Flow Chart - File Mark Stop Circuit 3-14
3-10 Write Enable Circuit 3-18
3-11 Typical Stage in Write Data Circuit 3-19
3-12 Motion Control Circuit 3-21
3-13 Loop Sensing in Vacuum Columns 3-23
3-14 Servo Drive Control Circuits (Take- Up Reel) 3-24
3-15 Ready Circuit 3-28
3-16 End of Tape Circuit 3-29
3-17 Search Load Point Circuit 3-30
3-18 Fault Circuit 3-33
3-19 Rewind Circuit 3-34
3-20 Rewind Unload Circuit 3-36
v
FIGURES (CONT'D)
Chapter 3 - (Cont'd)
3-21 Move to Load Point Circuit 3-37
3-22 Load Tape Circuit 3-39
3-23 Load Tape Operation 3-44
3-24 Rewind Operation 3-46
3-25 Rewind Unload Operation 3-48
TABLES
Chapter 1 - Description
1-1 Detailed Specifications 1-9
Chapter 2 - Operation
2-1 Manual Controls and Indicators 2-4
Chapter 3 - Interface Considerations
3-1 Communication Lines 3-2
3-2 Read Sequence 3-12
3-3 Photosense Circuit Description 3-24
3-4 Load Tape Operation 3-43
3-5 Rewind Operation 3-47
3-6 Rewind Unload Operation 3-49
vi
PREFACE
The Control Data 606 Magnetic Tape Transport is a high speed input/ output unit specif-
ically designed to provide the high performance storage capabilities required by
Control Data computers and data processing systems. Although the information con-
tained in this manual is based on the 606 transport, the discussion is generally
applicable to all 600 Series Magnetic Tape Transports.
Information is stored in the 606 on magnetic tape in the form of magnetized spots or
bits. Magnetic tape is used as the record media because modern data processing
systems require extensive files of input data which can be permanently recorded on
magnetic tape. The files, once stored on tape, can be used over and over as input
information, thus eliminating the costly process of re-entering new input data.
Although information recorded on tape is permanent, it may be erased and replaced
by new information, when desired.
The 606 may be used with computers in an on-line capacity, or with external equipment
in an off-line processing system. When used on-line, for example, the operation of
the 606 may be externally controlled by the Control Data 160-A, 1604- A, 3600 or other
computers. In an off-line system, the 606 is under manual (local) control and is used
with other peripheral equipment such as the Control Data 1612 Line Printer, 167 Card
Reader, etc. In both cases, the tape transport may function both as an input and output
device. The transport, in other words, accepts and stores information from the com-
puter or peripheral equipment and/ or sends data to the computer or peripheral
equipment.
Transfer of data and the exchange of control information from computers or off-line
equipment to magnetic tape is via a separate external control unit. The control unit
provides the timing information necessary to buffer and control the flow of information
into and out of the tape transport.
vii
Description
The Control Data 606 Magnetic Tape Transport includes the operational features and
logic found to be most desirable for efficient system operation. These advantages are
being fully utilized in Control Data computer systems and can also be used in systems
supplied by original equipment manufacturers.
PHYSICAL DESCRIPTION
The location of major components in the 606 tape unit is shown in figure 1-1. The tape
unit is 72 inches high, 33 inches deep, 28 inches wide and weighs 800 pounds. Detailed
specifications are given in table 1-1.
Each tape unit includes self-contained read/write electronics, control logic and power
supplies. Because the use of shared components has been eliminated, each 606 oper-
ates independently of other units in the system. In multiple unit installations, for
example, certain searching and positioning operations may be done simultaneously by
two or more units. Any 606 may be removed from the line for testing and maintenance
without affecting the operation of the remaining units.
A bank of switches and indicators on the front control panel allows the operator to
monitor and manually control tape operations. A bank of switches and indicators on
the rear maintenance panel provides complete operator control during test procedures.
The logic control section, mounted at the rear of the cabinet on a hinged chassis,
controls the operation of the 606. The logic section consists of a number of circuits
mounted on separate pluggable printed circuit cards. The circuits are similar in
construction to those used in Control Data computers.
Power input to the 606 is provided by any standard 208 vac, three phase, 15 amp ser-
vice line. All internal a-c and d-c voltages are developed and distributed by the power
supply unit located at the lower rear of the cabinet.
1-1
Control Switches and
Indicators
Maintenance Panel - - - - , . . .......::~~
Logic Section -~!;.~:tt"E""iiii!M_
Power Supply
Figure 1-1. Tape Transport, Front a nd Rear View
1-2
FUNCTIONAL DESCRIPTION
TAPE FORMAT
Magnetic tape provides a high speed, non-volatile storage medium for recording and
retaining information. The tape has a plastic base and is coated on one side with a
magnetic oxide. The coating consists of minute particles of iron oxide mixed with a
binding agent. It is upon this coating that information is recorded. Extreme care is
taken in the manufacture of the tape in order to eliminate any imperfection that could
cause errors. Each roll of Control Data magnetic tape is therefore thoroughly tested
before being used to guarantee its recording characteristics and performance.
Information is read (detected) or written (stored)by passing the oxide side of the tape
over read/write heads. Information may be written on any of seven independent tracks on
the tape. During a read or write operation, seven recording heads are placed vertically
across the tape; therefore 7 bits may be simultaneously recorded, 1 bit on each track.
A seven track non-return-to-zero (change-an-ones) recording scheme is used. In this
system, magnetic particles on the tape are aligned