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XX-3F9DC-09

2000

14 pages

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Document:	PDP-11 Resource Timesharing Systm RSTS-11
Order Number:	XX-3F9DC-09
Revision:
Pages:	14
Original Filename:	Digital.PDP-11.1970.102646128.pdf

OCR Text

resource sharing: timesharing use of high-speed input/outp
RSTSll terminal users may have
exclusive use of any peripheral 09 a
timesharing system (except the disk,
which is a shared device). They may use
it as long as needed, and then return it
for assignment to another user. The
ability to enter, store, and retrieve
programs and data files using high-speed
peripheral devices makes RSTS-11 a true
general-purpose problem-solving system.

Examples of the value of the Resource
Sharing concept are: one user may use the
line printer, card reader, tape and
disk files for performing a "batch"
adrmnistrative data processing task;
another terminal user may use a
DECtape unit for retrieving or creating a
tape file intended for off-line storage;
and when thecard reader is free, yet

another terminal
punched-card file w h i 8
BASIC program he ha%
off-line card punch.

RSTS for business and administrative problem solving
One of the most difficult problems facing
business today is increasing the
productivity of costly, hard-to-find clerks
and secretaries. RSTS-11's power and
flexibility offer the benefits of reduced
costs, increased customer satisfaction,
and increased job satisfactionfor clerical
workers.
How RSTSll Benefits Administrative
Applications
Journals, general ledger, and other
account records are stored on-line for
quick access from high-speed disk
storage, thus reducing paper handling.
Because RSTS-11 is a full-scale
computer system, more of the steps and
decisions in accounting applications
can be automated thus reducing the
drudgery of accounting operations and
the possibility of human errors.
Records are kept on-line. They can be
updated quickly and retrieved easily
for generating timely, detailed reports
for better management control.
Customer satisfaction increases when
an on-line, RSTS-11 customer account
inquiry system reports account status
in a matter of seconds.
Operating costs are reduced because
accounting personnel can be trained
quickly, work more effectively, make
fewer mistakes, and have to handle less
paper.

Potential On-Line Administrative
Applications include:
Order Entry/Accounts Receivable/
Sales Analysis
Inventory Control/Accounts Payable
Data Entry with automatic error
checking, editing, and verification
Inquiry-Response for "instant" access
to records.

RSTSll can be dedicated in
administrative application systems. The
power and versatility of RSTSll permit
terminals to be used for computational
problem solving simultaneously with the
execution of administrative applications.
Thus, the value of RSTSll in an
organization can be enhanced, for
example, by installing a number of
RSTS-11 terminals in the
engineering area as well as in
administrative offices.

R S T S in schools
for interactive timesharing and administrative applications
The low operating costs of RSTS-11
make it an ideal computer system for
schools. Up to 16 students may have
simultaneous, interactive, access to a
true timesharing computer. And, an
expanded RSTS-11 hardware
configurationlets you execute administrative applications at the
same time while students are using the
system for instruction.
Students with little or no computer
background can use RSTSll terminals
for developing computer concepts. More
advanced students meanwhile, can
perform more complex problem-solving
exercises. This is because RSTS-11has
powerful features such as terminal-user
core space as large as 16,384bytes (8192
words). Hence RSTS-11 is valuable in
many curriculum areas. For example,
students can conduct independent
research in simulations, capital budgeting,
and computer-aided instruction system
development.
BASIC-PLUS programming language is
so versatile that students may progress
from the introductory stages of computer
education to learning very advanced
concepts in computer science and data
processing. It is not necessary to interrupt
the students' progress to learn a new
language because they have "outgrown" a
programming language. The success of
BASIC as an introductory programming
language has been proven with thousands
of students, beginning with those at
Dartmouth College, where BASIC was
developed. As students become ready,
they may be introduced to more and
more of the extended features of
BASIC-PLUS. For example, introduction
of the PRINT USING statement (useful
for complex formatting of printed output)
may be deferred until the students are
assigned more sophisticated projects.
Thus, students with a broad range of

RSTS-11 features make it an ideal system
for the development of low-cost
Computer-Assisted-Instruction (CAI) or
Computer-Managed Instruction (CMI)
systems. CAI and CMI system operations
consist primarily of processing i f text in
the form of character strings.
BASIC-PLUS includes extensive language
features which simplify development of
efficient CAI and CMI text processing
programs. For example, special functions
are included that can measure a student's
response time or continue a program if
there is no response.
Administrative avvlications
can be run
* *
simultaneously with timesharing terminal
use on expanded RSTS-11 hardware
configurations.For example, a Grade
Reporting System may be executed
utilizing a card reader, high-speed line
printer, and magnetic tape or disk files
while up to 1.5students are each using an
interactive terminal to complete their
assignments.

RSTS for inhouse timesharing in scientific and industrial environments
BASIC-PLUS with its powerful extended
language features makes RSTS-11 an
ideal tool for scientific and engineering
problem solving. RSTS-11 terminals are
easier to use and more flexible than a
desk calculator-even for simple
problems. And, RSTS-11 has large-scale
system features: user core storage of up to
16,000bytes per terminal; additional
programs that can be quickly called from
an on-line program library. Sophisticated
or simple, all applications can be handled
with ease. RSTS-11 terminals can be
placed where the problems are.
High-speed paper tape and punched-card
invuts lets data collected from
experiments to be quickly entered and
analyzed. RSTS-I1 terminals bring
computational power to engineers and
scientists with the convenience,
accessibility, and economy heretofore
available only with deskcalculators. And,
if you're already using a subscription
timesharing service, RSTS-11 gives you
the same familiar programming language
but with many extra extended benefits.

the UNIBUS""
-pathway to
system expansion
The PDP-11 UNIBUST% the PDP-11's
unique means for intercommunications
among all system componentsof RSTS-11.
Any unit -including processor, memory,
disk, terminals, and other peripheral
devices-may be added to RSTS-11
simply by plugging the unit's controller
into the UNIBUS. This modularity means
that RSTS-11 can grow as your needs and
budget grow. Your investment in RSTS-11
is safe and never becomes obsolete. All
future devices for the PDP-11 will always
be compatible.

RSTS-11
configurations

expandibility

Because of PDP-11 flexibility, the initial
RSTS-11 configurationsmay be tailored
to closely fit your needs and budget. And,
when these needs and budget grow, the
configuration may be expanded by
adding equipment from a broad range of
optional hardware.
A minimum RSTSll configuration
includes: a PDP-11 computer with 20,480
words of memory, a fixed-head disk unit,
a dual DECtape magnetic tape unit, a
real time clock, a bootstrap-loader
read-only memory unit, from one to 16
terminals, terminal interfaces and
mounting hardware.

The RSTS-11 configuration may be
expanded either initially or at a later
time with any of the following:

This configuration also supports the
program development system, DOS,
which may be used for the development
and execution of FORTRAN IV and
assembler-language programs. See page 11
for further details.

Additional fixed-head disk units to
increase the on-line file capacity
available to users.
Moving-head, removable disk
cartridge drives for large-scale on-line
file capacity.
Moving-head disk, removable disk
pack units similar to the IBM 2314 f o ~
on-line capacity up to 32 million byte
Additional terminals and terminal
interfaces (up to 16 total). Terminals
may be typewriters, Teletypes, the 30
character-per-second DECwriter,
the high-speed DECdisplay for sil*
terminal operation.
Communications line terminal
interfaces for remote operation of
interactive terminals via telephone
lines.

Card reader for entering punched
card files.
- Line printer for producing hard-copy
output at high speed.
Additional DECtape transports for
expanding the amount of on-line serial
file capacity.
Industry-compatible one-half inch
magnetic tape transports for
large-scale on-line serial file capacity
and for transferring data files manually
between RSTS-11and other computer
systems.

High-speed paper tape reader and
punch for economical input and output
of files at medium speed.
Additional core memory for increasing
the core storage area per terminal from
8192 bytes (on the minimum
configuration) to a maximum of 16,384
bytes. Addtional core also helps
improve the responsiveness of the
system.

matrix operations

string operations

print formatting

A variety of operations are available
which permit efficient operations upon
one and two dmensional arrays of data.
Matrix data elements may be character
strings, floating-point, or integer-numeric
quantities.
Operations include:
MAT READ
MAT PRINT
MAT INPUT
Initialize matrix to zeroes, ones, or the
identity matrix.
Matrix addition, subtraction,
transposition, and inversion.
Large arrays may be dimensioned,
stored, and accessed on an element-byelement basis in an on-line disk file,
thereby conserving user core memory
space.

Many applications, including ComputerAssisted Instruction and business data
processing, require efficient processing of
strings of characters. A string may be up
to 512 characters in length. String
operations available include:
Concatenation for appending one
string to the end of another.
CHANGE a one dimensional array of
characters to a string or a string to a
vector (In RSTS-11, a character string
need not be considered as a onedimensional array of characters).
A full set of relational operators for
comparing one string to another.
LENGTH function for determining the
number of characters in a string.
LEFT, MID, and RIGHT functions for
extracting a string of characters
contained within a larger string.
INSTR for searching for a substring
within a string.
SPACE function for creating a string of
N space characters.

Many applications, such as business data
processing, require more flexible control
of the printing format than Dartmouth
BASIC allows. BASIC-PLUS includes a
PRINT USING statement which may be
used to achieve precise definition of
printed data format. PRINT USING
allowscharacter, decimal, and exponential
data field lengths and positions to be
defined, and mixed, for a print line. In
addition, leading dollar or asterisk
symbolsmay be "floated" to automatically
precede the most significant digit of
decimal fields. Trailing minus signs for
data fields may be specified for
compatibility with accounting report
standards.

extended program statement coding

integer data type

The effectiveness of RSTS-11 in solving problems in a broad variety of application
areas is significantly increased with the addition of numerous extensions to the
structure (syntax) of the BASIC program statements. These highly flexible program
statements permit more concise expression of complex program steps. Here are a
few examples:

BASIC-PLUS includes the definition of
integers in addition to strings and
floating point numbers. Integers are
whole numbers in the range of - 32,767 to
32,767. The use of integers often
increases the execution efficiency of
programs. The most common uses of
integers are in counting and
indexing operations.

LET A1=PlkR1 IF R1=5.0 OR R1=0.0
G O T 0 5530 UNLESS Xl$>Yl$ AND Z$="ABC
LET (Yl,Zl)=Zl+3 FORZ1=1 TO L
IF X>Y AND Y >Z THEN Z=X ELSE Z=Y
FOR I=X (J) STEP 3 WHILE L$ (I)=L$ (I+1) AND J I - I 4 2
ON X(2,5) G O T 0 100,150,200,250,300

interval timer

program recovery from input/output errors
One of the more frustrating situations for a timesharing terminal user is when his
program is cancelled because an input/output error condition occurs (perhaps
temporary) and causes all results created (in a file, for example) to that point to be lost.
This situation, although rare, may be eliminated in RSTS-11 applications by use of the
ON ERROR G O T 0 statement. This subroutine call statement is triggered by a variety
of input-output operation errors. The call subroutine is passed a value which
identifies the error type, and attempts to recover from the error condition. If the
subroutine is successful, normal execution of the application program resumes.

In some timesharing applications, the
length of time that a terminal user takes
in responding
at his
- to a message
- printed
terminal is a significant variable. The
WAIT function provides an interval timer
feature which may be used for signaling
the program that the terminal user has
not responded within some predetermined
length of time. One example of the use of
the WAIT function is in Computer-Aided
Instruction applications where one
measure of student performance is his
"think time." If he takes more than 5
seconds, for example, to respond to a
question, the computer can restate the
question in another manner, and record
the delay as one element of his overall
performance.
An additional feature provides year,
month, day, and time-of-day information
to the RSTS-I1 program.

file handling
input-output capability on-line file library

file security

Small computer timesharing does not
imply a reduced need for file handling
capability. RSTSll supports a broad
range of peripheral devices with costs
and characteristics suitablefor a variety
of problems. Each peripheral device may
be directly accessed by a terminal user
to help him solve his problem in the most
effective manner:
Low-speed paper tape at ASR
Teletype terminals for short or
infrequently used programs and data.
High-speed paper tape reader and
punch for somewhat larger files.
Industry-compatible DEC Magtape and
inexpensive, high-performance
DECtape for unlimited program and
data file storage. Low-cost reels of
DECtape offer many benefits over
punched cards for off-line file
storage: faster input/output, reduced
storage space, ease of handling, and
increased reliability.
DECpack removable disk cartridge
drives, DECdisk fast-access fixed-head
disk units, and removable disk packs
with a capability of 32 million bytes,
total, for on-line storage of
frequently used files.
Punched-card files may be created
off-line for data collection or classroom
programming and then entered into
RSTS to build data and program files.
Files may be printed at high speed
under terminal user control via a
high-speed line printer.

Each terminal user has full control on
d
the degree of privacy he desires for each
file he creates. The disk librarv file
directory system, which provides
efficient access to files, includes a
privacy-protectionlevel which may be
set only by the terminal user responsible
for creation of the file. Personnel records,
for example, can be given absolute
protection from all other users. Other
levels of protection include access
limited to a particular group of users,
read only, write only, and public.

RSTS-11 users may create and have
high-speed access to program and data
files stored on disk units with total file
space of up to 32,000,000 bytes. Files
may be created for either sequential or
random access processing, depending
upon the requirements of a user's
application. Up to 12 files may be open
and accessible from a single program at
any one time. The number of files a user
may have stored in the disk library is
bounded only by the total system disk
capacity and the library demands of
other users.
An on-line file library system means that
RSTSll terminal users have the
convenience of almost instant access to
any desired file or file item. Terminal
users are spared the problems and
frustrations of handling paper tape each
time a program is to be executed. Many
applications such as on-line customer
inquiry-response are possible with the
large-scale file library system of
RSTS-11.

' running other languages on RSTS-11
-

he need for a variety of programminglanguages, the RSTSll hardware
10116
rnav be used for the develment and execution of FORTRAN IV and

assembly-languq; programs using the
development software system, DOS.
PDP-11 FORTRAN includes language compatibility elements that permit transfer of
FORTRAN IV programs from other systems such as the IBNI 1130to the PDP-11. The
language, which is an ANSI-standard compatible FORTRAN IVl will .operate in the
minimum RSTS hardware configuration described on page 6. DOS is a disk-resident
softwaresystem which enables a user to both develop and runhis own programs. A
series of softwaremodules permits creation, debugsing and editing of programs with a
series of simple commands. During the program run, the monitor furnishes all the I/O
device routinesIloaders and basic resources accountingnecessary from disk resident
files.AdditionaI features af DOS include random access and sequential files, file
protection for user privacy, sirnultaneaususe of inputfoutput devices with processing
and input/output device independence.

digital 4 uipment corporation and its timesharing experi rice
Your decision to buy a minicomputer
timesharing system is an important one.
The company behind the system is *
important too.
Digital Equipment Corporation is the
world's largest and most experienced
manufacturer of small computer
systems. Over 11,000 Digital smallcomputers are now in use performing a
large variety of tasks. Digital has a
network of sales, support, and field
service offices throughout the United
States, Europe, Canada, The United
Kingdom, Australia, and Japan. These
offices are prepared to respond quickly
to your needs for training, programming
assistance, and maintenance.
Digital produced the first minicomputer
timesharing system-TSS-8, a 16-user
system based on the popular PDP-8
computer. The features built into RSTS-11
reflect Digital's experience in responding
to the needs of the many owners and
users of TSS-8 in schools, research and
development organizations and
timesharing utilities. The developers of
TSS-8 system software participated in
the development of RSTS-11. You benefit
from Digital's knowledge about
minicomputer timesharing.
Digital also produces thel27-user PDP-10
timesharing system, giving you the added
benefit of large-scale experience. This
background has allowed Digital to
produce the best medium-scale systemthe RSTS-11; one that has many of the
best features of both large and small
scale systems.

Dallas. Texas 75247
Telephone (214)838-4880

*%ANPA

%IS C i e a w l w Place, sclb fda.
Atlanta. Georg~a90340
Telephone (404)-4583133/3134/3135 TWX 810-7574223
KNOXVILLE
5731 Lyons View Pske. S W.. Knomille. Tenn. 37919
Telephone: (615)-5886571
TWX: 8105830123

CENTRAL
REGIONAL OFFICE:
1850 Frontage Road. Northbrook. lllmois 60082
Telephone (312)-4982500
TWX 9106860855

Pmburgh. Pcwlvania 1953

CWm UM,E n o l d , Nraw
Telephone. (201)871-4984. (212)-5944355, (212)-7360447
TWX 710-991-9721
N.-.
E W. .
IERSEY
-. .-- .
1259 Route 46. Parsipparty. New lersey 07054
Telephone: (201)-3353300
TWX: 710.987-8319
PRINCETON
US. Route 1
Princeton. New lersey OBYlO
Telephone: (809)452-29U)
TWX: 510685-2338
LONG
-. ISLAND
1919 i J d i i e ~ i u n t r yRoad
Centereach. L.I.. New York l l i 2 0
Telephone: (516)5855410/5413
TWX: 510-P&8505
PHILADELPHIA
Station Square Three. Paoli. Pennsylvanm 1931
Telephone: (215W4749W/441O
Telex: 5106688395
WASHINGTON
Execut~veBu~ld~ng
6811 Kendworth Ave.. Riverdale. Matyland 2M140
Telephone (301)-779-16W752-8797
TWX 710-8269BM
DURHAWCHAPEL HILL.
2704 Chapel Hlll Boulevard
Durham. North Carolma 27707
Telephone (919)489-3347
TWX 5109270912

Teleohone 14121-2458500
TWX 710-797-3657
. .
CHICAGO
1850 Frontage Road. Northbrook. Illmom 60082
Telephone 13121-4982500
TWX. 9106860855
ANN ARBOR
230 Huron V~ewBoulevard. Ann Arbor. Mtchigan 48103
Telephone (3131-761-1154
TWX: 810-223-6053
INDIANAPOLIS
21 Beachway Drive - Sulte G
Ind~anapolls,Indiana 46224
Telephone Ki17)-24%8341 TWX 8103413438
MINNEAPOLIS
Sulte 111. BMO Cedar Avenue South.
Mmneapol~s.Minnesota 55420
Telephone (612)-8&(-.1092
TWX. 91LL57€-2818
CLEVELAND
35104 Euclid Ave
Park H ~ lBldg
l
Willoughby. Ohio 4 4 M
Telephone (2161-94&6464
TWX 8104274808
ST LOUIS
Sulte 110. 115 Progress Pky Maryland He~ghts.
M~ssourl63043
Telephone (314)472-7520
TWX: 910-78+0831
DAYTON
3101 Kettermg Blvd Dayton. Ohlo 45498
Telephone (513)298-7377
TWX. 810459-1676
MILWAUKEE
Suite 107.2825 N. Mayfair Rd.. Milwaukee. Win. 5222

TWX: 910.881-4MK1

HOUSTON
3417 Mdam Street. Suite A. Houslon. Texas 770M
Telephone. (713>5242981
TWX: 810881-1651

WEST
REGIONAL OFFICE
560 San Antonlo Road. Palo Alto. Californla 94306
Telephone (415)3265&(0
TWX. 910579-1288
ANAHEIM
801 E. Ball Road. Anaheim. California 92805
Telephone (714)-7768932/8730
TWX: 91MS1-1169
WEST LOS ANGELES
1510 Cotner Avenue. Los Angeles. Californna 90025
Telephone. (213-479-3791/4318
TWX: 910-342-6~98
SAN FRANCISCO
560 San Anton10 Road. Palo Alto. Callforn~a94306
Telephone (4151.3265640
TWX: 9109731268
OAKLAND
7850 Edgewater Drwe
Oakland. California 94621
TWX. 9103667238
Telephone: (415)6355453/7830
ALBUQUERQUE
6303 Indian School Road. N E
Albuquerque. N.M 87110
Telephone (sos>2985411/5r128 TWX: 910-989-0814
DENVER
2905 South Colorado Blvd Sulte #5
Denver. Colorado 80222
Telephone: (303)-757=/75glg56/7581658
TWX 910-931-2650
SEATTLE
1521 1 M h N.E.. Bellevue. Washington98005
Telephone: (208)4544%/4555404
TWX. 910.443.Po6
SALT LAKE CITY
431 South i r d ~ a s t Salt
.
Lake City. Utah &I111
TWX. 910.92Telephone. (801-9838
PHOENIX
307 E. Southern Ave.. Tempe. Arnona 85281
Telephone: (802>%7-1618 TWX: 91095M691
PORTLAND
19015 Southwest Pac~hcHlghway. Tlgard. Ore. 97223
Telephone: (503)63P8832/88&0
TWX: 9104S8792

CANADA

GERMANY (cont.)

D~gitalEquipment of Canada. Ltd.
CANADIAN HEADQUARTERS
150 Rosamond Street. Carleton Place. Ontario
Telephone: 16131-257-2615 TWX. 610-561-1651
OTTAWA
120 Holland Street. Ottawa 3. Ontario
Telephone 16131-W2193
TWX 610-5Mgg07
TORONTO
230 Lakeshore Road East. Pon Credit. Ontario
Telephone: i416l-278-6111
TWX: 610.4924326
MONTREAL
9675 Cote de Llesse Road
Dowal. Quebec. Canada 760
elephone: 5148389393
TWX: 6104224124

SWITZERLAND

MUNICH
8 Muenchen 13, Wallensteinplak 2. Germany
Telephone: 0811358011-15
Telex: 811-%WMl
HANOVER
D~~IG
Equipment
I
Corporation GmbH
3 Hannover. Germany. Podblelskiatrass. 102
Telephone: 0511BO70-95 Telex 922-952

Digital Equ~pmentCorporetlon S A.
GENEVA
81 Route De L'Aire
1227 Cerouge / Geneva. Switzerland
Telephone: 42 79 50/58/99
Telex. 22 883
ZURICH
Frelgutstrasse26, aMYL Zurlch. Switzerland
Telephone (51) 36 76 23

Edmonton. Alberta. Canada
Telephone: (4W)43Wm
TWX: 610891-2248
VANCOUVER
Dtgital Equ~pmentof Canada. Ltd
WO West 12th Avenue
Vancouver 9. Br~tishColumb~a,Canada
TWX 61aEM9-2W6
Telephone (604)73g5616

SOUTH AMERICA
COASIN S A.
V m y del Pmo 4071 Buenos Alres. Argentina
Telephone: 52.3165
Telex 012-2284

EUROPEAN HEADQUARTERS
Dlg~talEqu~pmentCorporation Internat~onalIurope
81 Route De L'Adre
1227 Carouge / Geneva. Switzerland
Telephone: 42 79 50/58/59
Telex. 22 B83

GERMANY
Dig~talEquipment GmbH
COLOGNE
5 Koeln. Bismarckstrasse7. West Germany
Telephone: 52 21 81
Telex 888-2269
Telegram: Fhp Chip Koeln
FRANKFURT
A M Forsthaus 5 7
8078 Neu-laenburg-Gravenbruch.Germany
Telephone: 08102-5526/5529

ENGLAND

ITALY

Dlgital Equipment Co.. Ltd
READING
8 Tessa Road, Readlng. Berkshire. England
Telephone. 073+S89ga/4/5/6
Telex: &(327
MANCHESTER
6 Upper Precinct. Worsley
Manchester. England M25AZ
Telephone. 081-7WE4ll
Telex 888868
LONDON
B~ltonHouse. Uxbr~dgeRoad. Ealing. London W.5
Telephone 01-679.2781
Telex 22171

FRANCE
Equipement Dlg~tal
PARIS
327 Rue de Charenton. 75 Par@12 "I=.
Telephone: 3VFE-07
Telex: 21339

Dlgltal Equipment S.p.A
MILAN
Corso Garlbaldi. 49. 20121 Milano. Italy
Telephone 872 748. 872 894. 872 394
Telex:

AUSTRALIA
Digital Equipment Australia Ply. Ltd
SYDNEY
75 Alexander St.. Crows Nest. N.S.W. 2065 Australla
Telephone: 43925BB
Telex. Am740
Cable. Dialtal. Svdnev
. .
MELBOURNE
60 Park Street. South Melbourne. Victoria. 3205
Telephone: M 1 4 2
Telex: AA307CU
WESTERN AUSTRALIA
W3 Murray Street
West Perth. Western Australla 6W5
Telephone: 21-4893
TeleB A.492140
BRlSBANE
139 Merwale Street. South Br~sbane
Queensland. Australia 4101
Telephone. 44047
Telex: AA4K616

France

BENELUX
THE HAGUE
D~gitalEquipment N.V.
Sir Wlnston Churchillaan 370
Rllswllk (2-H). Netherlands
Telephone: i'O-S95180
Telex: 32533
BRUSSELS
Digital Equlpment N.V.S.A
106 Rue D'Arlon
1040 Brussels. Belgium
Telephone: 02-139256

SWEDEN
Dlgltal Equipment Aktiebolag
STOCKHOLM
Vretenvagen 2. 5-171 54 Solna. Sweden
Telephone, 98 13 SO
Telex lm SO
Cable Dag~talStockholm

JAPAN
TOKYO
Rikel Trading Co Ltd (sales only)
Kozato-Kaakan Bldg
No 1814. N~sh~sMmbashi
1-chome
Mlnato-Ku. Tokyo. Japan
Telephone: 5915246
Telex 781-4208
D~gttalEquipment Corporetlon International
Kowa Bullding No. 17. Second Floor
2-7 N~sht-Azabu1-Chome
Mmato-Ku. Tokyo. lapan
Telephone: 40C5894/6
Telex. TK8428