UNIVAC 490 Operating and maintenance instructions

o
GENERAL DESCRIPTION. .
f:he UNIVAC ® 490
Real-Time Sysf:em
•

GENERAL DESCRIPTION
UNIVAC 490
Real-Time Sys-tem
© 1961 • SPERRY RAND CORPORATION

Contents
1. UNIVAC 490 REAL-TIME SYSTEM
The Real-Time Concept. ............ ........................................... . 1
General Characteristics of
the Real-Time System.................... . ...... ... .. 2
High-Speed Communications
Linkage........................................... 2
Data Storage
Facilities. . . . . . . .. . . .. . . . . . .. . . . . . . . . . . .. . . . . .. . . . . .. . . . . . . . .. . . . . . 2
Features
and Applications ...................................................... 2
Processing
Interrupt..... .......... .. ....... . .. .. .. .. ... ...... .. . .... .. .. . . .. 2
Solid-State Design
........................................................... 3
Computer-to-Computer
Configurations....................................... 3
High-Speed Random Access
Storage.................... ... ............... ... 3
A "Time Conscious" System
................................................. 3
Incremental
Clock...................................................... ..... 3
Incremental Interrupt
Clock........................... ............ ...... ..... 3
Day
Clock................................................................... 3
High Internal Computing Speeds........................................... .. 4
Equipment
Enclosure..................................................... ... 4
Flexible Input-Output
Facilities.......................................... ..... 4
Automatic Programming
..................................................... 4
Floating-Point Arithmetic
.................................................... 4
Programming
Checks......................... ............................ ... 4
Special Programming
Features.............................................. .... 5
Powerful Instruction
Repertoire.............................................. 5
Absolute Efficiency
.......................................................... 5
Library of Programmed
Routines............................................. 5
Core Storage Search
......................................................... 5
Wired
Memory. . . . . .. . . . . . . . . .. .. . . . . . . .. . . . . . . . . . . . .. . . . . . .. . . . .. . . . . . . . . .. . 5
Application Versatility
....................................................... 6
2. REAL-TIME COMPUTER
Storage Section ................................................................. 7
Octal Notation. . . . . . . .. . . . . .. . . . . .. . . . . .. . . . . . . . . . . . . . .. . . . .. . . . . .. . . . . .. . . . . 7
Control Section
................................................................. 8
Arithmetic
Section..... .................................. ....................... 8
Arithmetic Registers (Operational Registers)
................................. 9
Transient Registers
.......................................................... 10
Operator Console ............................................................... 11
Computer Control Panel
..................................................... 11
Console Keyboard and Printer
............................................... 11
Wired
Memory. . . . . . . .. . . . . . . .. . . .. . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . .. . . . . . . .. 11

3. SYSTEM COMPONENTS AND CONFiGURATiONS
Central Site Equipment ...................................................•..... 12
Peripheral Units............................................................. 12
Peripheral Systems ..........................•.•............................. 12
Magnetic Drum Storage .......................................•.....•........ 14
Magnetic Tape Storage ...•..............••.................................. 15
High-Speed Card Reader... . . .. . . . . . . . . . . .. . . . . .. . . •. . .. .. . .. . .. . .. . .. . .. . . .. 16
Punch-Verifier Unit ......•.........•..........................•.............. 16
High-Speed Printer ............•............................................. 17
Transmission and Communications .....................................•....... 18
Input-Output Channels ...............................•.....•................. 18
Data Transfers ............................•...................•............. 18
Buffer Mode. . . .. . . . . . .. . . . . . .. . . . . . •. . . . . . . . .. . .. . . . . .. . . . . . . . . . . . . . .. . . . . .. 18
I nput-Output Control ..........................••............................ 18
External Equipment Requirements ........................................... 19
Remote Input-Output Devices ..........................................•........ 19
Keyboard Printer ..........•...............•................................. 19
Uniset Console ......•...........••.................•........................ 20
The Uniset .................................................................• 21
Format Control Panel ..........•... '. . . .. . . . . . . .•. . .. . . . .. . . . . . •. . .. . . . . . . . . .. 21
Communications Equipment ......................•............................. 21
Communications Systems ...................................................... 23
Party Line Network ............................................................. , 23
Scanner -Selector
..................•...............•.........•.............. 23
Party Line Communications System ............................................. 23
Transfer Function ...............................................•...•....... 24
Line Switching Network (Direct Distance Dialing) ..............................•. 24
Communications Control Unit (Telegraphic Half-Duplex) ........................ 24
Communications Equipment for Special Devices ................................. 26
4. INSTRUCTIONS
Instruction Word ............................................................... 27
Instruction Cycle ...................................................•........... 27
Instruction Repertoire.......................................................... 28
Shift Instructions ............ , ............ " .................... '" ............. 28
Simple Read Instructions ....................................................... 29
Store Instructions .............................................................. 29
Arithmetic Read Instructions .................................................... 30
Comparison Instructions ........................................................ 30
Selective Instructions ...................................•....................... 31
Replace
Instructions ............................................................ 31
Jump Instructions .............................................................. 32
Special Program - Modifying Instructions ..•.............•....................... 33

just as feedback is used by a computer
to control a missile's path;: ....
• •• up-to-the-minute data from
a UNIVAC Real-Time System can help
influence the course of business curves.

1. UNIVAC 490 Real-Time System
The UNIV AC®490 Real-Time System is a
large-scale,
general purpose digital com-
puting system specifically designed for the
dynamic organization which has diverse
operations demanding stricter control
based on real-time computing. This new
system extends valuable techniques of real-
tinle processing, long restricted to a linlited
number of special military applications
such as missile guidance, to the broader
field of commercial problems.
Remington Rand's installation of UNIVAC
Airlines Reservation Systems at several
major airlines demonstrated the power of
real-time processing. A centrally located
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formation in a fraction of a second to ticket
offices scattered throughout the country.
The well-documented success of the Airline
Reservations System proved the potential
of real-time processing and served as the
incentive for its full development.
Now,
with the Real-Time System, the full
commercial
potential of real-time process-
ing can become an integral part of your
business, bringing with it an efficiency and
control only approximated by other devices.
In fact, just as feedback is used by a com-
puter to control a missile's path and coun-
teract disrupting forces, up-to-the-minute
data from a real-time system can help an
organization influence the course of a
number of its business curves as they are
formed.
THE REAL-TIME CONCEPT
The real-time concept is the fulfillment of
management's desire for a method of re-
versing the direction of a business curve
before it gains momentum and attains
black-and-white finality. Up-to-the-minute
indications of business activity enable the
real-time user to detect the suggestion of a
downturn and correct it immediately, in
much the same way as a guided missile's
course is
adj usted as it hurtles to its target.
If, for example, sales have dipped slightly,
the Real-Time Computer will allow man-
agement to discover this fact immediately,
instead of waiting for quarterly reports. As
a result, management's remedial actions
are effectively timed. And it is the timely
decision which has the greatest significance
in the intensified competition of business
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organizational activities, it is necessary to
utilize a real-time processing system, with
its ability to communicate with many
remote locations and its large storage fa-
cilities, to reflect sales, profits, costs, pro-
duction, and other pertinent data.
Thus, the real-time concept is a significant
advance in data-processing, a field which
heretofore employed batch processing only.
That is, master data, or information which
is altered infrequently or in a known man-
ner, was updated at intervals, upon the ac-
cumulation of enough transaction data, or
information characterized by essentially
random and unpredictable incidence. Real-
time processing, however, eliminates the
lag between the occurrence of transactions
and their postings to a master file. By up-
dating the master file immediately upon
receipt of a new transaction from a remote
source, the Real-Time System can present
a truly current report of the status of any
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application-a feat impossible for the batch-
processing computer
with its externally
stored master data.
GENERAL CHARACTERISTICS OF THE
REAL-TIME SYSTEM
The specific design and function of the re-
mote
input-output units of the UNIVAC
490 Real-Time System
are dictated by the
nature of the individual application. In
general, however, input units are able to
accept transaction data with speed and
reliability while the output units display
results
with accuracy and clarity. The com-
puting unit of the system is general pur-
pose, and therefore, ideal for all types of
applications.
High-Speed Communications Linkage
Common carriers, such as American Tele-
phone and Telegraph, Western Union,
American Cable and Radio, afford high-
speed communicationfacilities
for two-way
transmission of data between the central
site Computer and the remote input-output
units. Transactions originating at remote
points
are conveyed along these wires di-
rectly to
the Computer where they are im-
mediately evaluated
and processed. Then
the result is returned to the originator and
other appropriate distant points, the whole
transaction being accomplished in seconds.
Data Storage Facilities
Since the UNIVAC 490 Real-Time System
applies
transaction data to the master file
information as the transaction data occurs,
the system employs extensive data-storage
facilities which are capable of storing en-
tire master files of information. In addition,
these facilities
are of the random access
type allowing immediate access to master
file information.
FEATURES AND APPLICATIONS
In addition to existing applications best
performed by this system, there is a grow-
ing number of vital data-processing prob-
lems
that depend on this type of automation
-the UNIVAC 490 Real-Time System-for
their effective solution.
The many outstanding features of the
UNIV AC 490 Real-Time System are par-
ticularly suited to applications in which
processing timeliness is vitally
important,
perishabilityis a factor, or decision-making
is based on
data originating simultaneously
at separate, remote points. Some of these
features, such as solid-state components
and microsecond internal computing
speeds~ represent the latest design advances
in the electronic computer field. Other fea-
tures of the system, such as the ability to
communicate with remote locations and to
perform both real-time and batch-process-
ing applications, are entirely new develop-
ments.
Some
of the major features of the UNIVAC
490 Real-Time System
are described briefly
in the following paragraphs.
Processing Interrupt
An outstanding feature of the UNIVAC
490 Real-Time
System is its capacity to
process real-time and batch-processing
applications concurrently. This impressive
data-processing innovation is made possi-
ble
through a unique feature that permits
remote external units to interrupt Com-
puter processing with information of high
precedence.
With this feature the maximum process-
ing potential of the system is realized. For
example, when once the master data for a
particular real-time application is recorded
in storage, the Computer can be used to
process a
"batch" application. Then, when-
ever transaction data for the real-time
problem is entered into a remote external
unit, the Computer's batch-processing is
interrupted to permit handling the high
priority real-time transaction and sending
the processed results to the external unit.
Upon completion
of the real-time process-
ing,
the Computer automatically returns to
the batch application. Further, if the real-
time
information handled during the inter-
rupt bears on the interrupted application,
the latter can be updated by the real-time
data,
thereby assuring that all subsequent
processing is up
to date.

Sol id-State Design
The solid-state components and circuitry of
the UNIVAC 490 Real-Time System offer
numerous
advantages including standard-
ized production of components and the re-
duction
of maintenance procedures to a few
relatively simple operations.
In addition to
ease
of production and maintenance, solid-
state circuits also impart a high degree of
operating reliability to the Computer while
reducing
the power, cooling, and space re-
quirements
of the system.
Computer-to-Computer Configurations
The UNIVAC 490 Real-Time System's abil-
ity to coordinate, through communication
networks,
the activities of several Com-
puters located at various points, allows the
user to increase his data-processing system
to meet
any sudden business expansion.
High-Speed Random Access Storage
To meet the extremely demanding require-
ments of real-time processing, the
UNIVAC 490Real-TimeSystemisequipped
with data-storage facilities (drums, tapes)
that are more expansive and versatile than
those of most present-day computing sys-
tems. The Computer has an internal co:re
memory with a capacity of 32,768 or 16,384
30-bit words.
A "Time Conscious" System
Processing timeliness, an inherent charac-
teristic of real-time processing, requires
the system to be extremely "time con-
scious." Three precision electronic chro-
nometers provide
the system with a timing
sensitivity unmatched by other computing
systems.
Incremental Clock
Thisbuilt-in clock is used for a wide variety
of program-timing purposes. It can be used
to log
the receipt times of aperiodic real-
time
input data. Each input message and
its receipt time may be recorded together.
This clock is also used
in connection with
the preparation of statistical and analyt-
ical reports dealing with the frequency of
certain transactions.
Incremental-Interrupt Clock
This "program-set" clock counts up to
32,768 milliseconds. Upon reaching its up-
per limit, the Incremental-Interrupt Clock
unconditionally interrupts the Computer at
the end of the instruction being handled,
regardless of the type of instruction. The
clock count is maintained in core storage.
The Incremental-Interrupt Clock is vital to
the functioning of a real-time system be-
cause one
of the primary uses of this clock
is
timing subroutine operations. If a mo-
mentary fault arising from improper pro-
gramming throws the Computer into a
closed loop,
or if a fault occurring during
the execution of an instruction halts the
Computer, the Incremental-Interrupt Clock
restarts the Computer by means of an in-
terrupt, thus providing automatic fault
recovery. The interrupt can be used to no-
tify maintenance personnel that a closed
loop
has occurred. If completing an opera-
tion takes longer than desired, this clock is
also used to
interrupt the Computer and
thereby allow program attention to be di-
rected
to items of more immediate impor-
tance.
Day Clock
A feature particularly suited to real-time
problems is
the 24-hour Day Clock. As an
auxiliary device, this electronicclockcauses
an external interrupt of Computer process-
ing once every minute. Thus, "keeping
time" is placed completely under the pro ..
grammer's direction.
Since
program control is shifted once every
minute to a set address in the Computer,
the Day Clock can be used to initiate a va-
riety of subroutines. For example, by using
a compare routine on the address reserved
for timing purposes, reports can be gener-
ated at any desired time of the day, week or
month. These reports could provide up-to-
the-minute
information and analyses of
company status. Error-checking routines,
trace routines, output conversions, manage-
ment report programs, maintenance rou-
tines,
and memory dumps are some of the
many routines which can be initiated by
the Day Clock.
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High-Internal Computing Speeds
Along with its high-speed random access
storage facilities, which allow a high data-
transmission rate between the Computer
and peripheral units, the UNIVAC 490
Real- Time System also features instruction
execution times measured in microseconds.
Instruction access and execution time totals
12 microseconds for most instructions.
Equipment Enclosure
The physical arrangement of the Computer,
its peripheral units, and the operator's con-
trol panel demonstrate the UNIVAC 490
Real-Time System's revolutionary equip-
ment enclosureconcept. This modern equip-
ment installation technique affords the
operator an unrestricted view of all signifi-
cant indicators and displays. It also posi-
tions
the peripheral units within easy reach
to allow the operator to attend to them
when necessary.
Maintenance personnel, located outside
the
operator's enclosure, have unrestricted ac-
cess to all equipment even though it is in
operation. Any element of the system may
be monitored for maintenance without in-
terfering with operating personnel.
In terms of economy of installation, the
equipment enclosure design concept pre-
sents the additional advantages of greatly
reducing floor-space requirements and
eliminating the need for expensive false
floors.
Flexible Input-Output Facilities
The UNIVAC 490 Real-Time System can
communicate directly with a wide variety
of commercially available input-output
units and custom-designed data-originating
devices. The system's Computer is also
capable of communicating directly with
other computers. The inherent flexibility
of the system's input-output channels en-
ables the UNIVAC 490 Real-Time Com-
puter to perform this diversity of input-
output data communicating functions.
A
large number of system input-output
channels are employed for communications
between
the Computer and peripheral site
units such as high-speed printers, mass-
storage units, card readers, and tape-han-
dling units. These same channels
can be
used to accommodate
an almost unlimited
number of remote data-originating devices
by
using a special input-output buffermode.
Two
input-output channels are utilized for
communications between the UNIVAC 490
Real-Time Computer and other computers.
Automatic Programming
The system features a very flexible compil-
ing system which allows mnemonic expres-
sion
of computer-oriented instructions. In-
structions and addresses to which they
refer can be given alpha-numeric names.
Program check-out can be accomplished
with special aids which include post mor-
tem and register dumping routines. A sub-
routine mechanism facilities compilation
of subroutines into a final program. The
compiling system also has a high-level,
problem-oriented language in which com-
puter programs are written. This compiler
interprets general statements and auto-
matically generates the necessary machine
instructions which perform the stated
function.
Floating-Point Arithmetic
The UNIVAC 490 Real-Time Computer
floating-point format is based on a two-
program-word information unit, one man-
tissa and one characteristic word. The
length of the mantissa is' 28 bits, and the
length of the characteristic is 15 bits, in-
cluding a sign. It is a three-address system
in which four index-registers are used to
designate the operand and the function
codes. As a complete
software system, it
includes input-output conversion and func-
tion evaluation.
Programming Checks
An important characteristic of the
UNIVAC 490 Real-Time System is operat-

ing reliability, a mandatory requirement of
a system designed for real-time processing.
Although the system's reliability is
achieved through solid-state components, a
number of progran1 checks and error-de-
tection procedures also contribute to the
system's highly reliable performance. The
system features a routine for automatic
restarting after an error is detected and
corrected. Because transaction data in real-
time applications is usually independent
and unrelated to previously entered infor-
mation, the system provides a routine that
preserves the transaction data being proc-
essed should
an error occur.
SPECIAL PROGRAMMING FEATURES
Special programming features enable the
UNIVAC 490 Real-Time System to process
virtually any type of commercial or scien-
tific
data-processing application. In addi-
tion to latest engineering advances incor-
porated into the logic of the system, a host
of special software programming features
associated with the system allows the user
to cut programming costs to a minimum.
Powerful Instruction Repertoire
The sixty-two function code values in the
instruction repertoire can be modified by
the system to provide unlimited program-
ming versatility. Much of the real program-
ming power of the computer lies in the
unique format of the instruction word. Of
the thirty bit positions in the instruction
word, nine serve as special purpose desig-
nators. When these designators are used in
combination with the function codes, the
computer can perform more than 25,000
basic programming operations.
Absolute Efficiency
Execution of a stored program of instruc-
tions on the Real-Time Computer proceeds
in a series of steps. Very often, however,
the unique requirements of real-time prob-
lems necessitate programming a large num-
ber of jump and skip operations. The prev-
alence of these operations arises because
the processing activities of a real-time com-
puter involve serving a large number of
remote peripheral units that are constantly
demanding computer attention on an im-
mediate or near-immediate basis.
Since skip and jump programming opera-
tions are inherent in real-time processing,
the internal logic of the UNIVAC 490 Real-
Time Computer causes these operations to
be handled in a manner approaching abso-
lute efficiency. For example, because the
next instruction is in "review" while the
current instruction is being executed, a skip
instruction brings the computer-at no loss
of time-directly to the resumption point
without leafing through intervening in-
structions. Jump instructions are processed
by the computer with similar efficiency.
Library of Programmed Routines
A maj or problem often encountered in the
installation of a new type of computing sys-
tem is the large amount of programming
required to put the system in operation.
Because the UNIVAC 490 Real-Time Sys-
tem evolved from prototype systems which
are now performing successfully at com-
mercial,
government, and military installa-
tions, an extensive library of proven pro-
gramming routines, including compiler and
assembly systems, is available to the user
immediately.
Core Storage Search
From a programming standpoint, a very
desirable and practical provision of the
UNIVAC 490 Real-Time System is the fea-
ture which allows the entire core storage, or
selected portions of it, to be searched auto-
matically and rapidly. Programming the
search operation requires the use of only
two instructions.
Wired Memory
A permanent memory is built into the Com-
puter for program input and automatic
error recovery. It consists of sixteen 30-bit
words of storage, and is wired to fit the
specialized needs of the Computer user.
This storage may be accessed by a program,
but can only be changed manually.
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