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BRL 1964, RCA 3301 REALCOM, starting page 0230

    RCA 3301 REALCOM
    RCA 3301 REALCOM
    Radio Corporation of America
    Photo by Radio Corporation of America
    The RCA 3301 Realcom is an all-purpose electronic data processing
    system. The Realcom combines realtime, data communications and
    scientific computation capabilities with powerful random access and
    serial data processing. A single RCA 3301 Realcom can provide the
    entire range of data processing capability required for an
    organization's total business operations. Together, the RCA Realcom
    and RCA 301 form a compatible machine family.
    The computer is an all-purpose stored program digital machine
    utilizing transistor and diode circuitry. The machine consists of high-
    speed storage, micro-magnetic storage, program control, console and a
    power supply. The 40,000 to 160,000 character high-speed storage is a
    magnetic core, decimally addressed, random access device with a memory
    cycle time of 1.75 microseconds. The micro-magnetic storage is
    utilized for registers and temporary storage, with a cycle time of 250
    nanoseconds. The program control unit contains circuitry for the
    interpretation and execution of the instructions, controls the
    interrupt system and performs automation accuracy checks. The console
    contains an operator's section to monitor normal operations and a
    maintenance section houses the indicators and switches needed for
    maintenance. The power supply unit supplies power to the Processor,
    Control Modules, and certain InputOutput devices.
    Five operating modes are available in the RCA 3301 computer in
    addition to buffered input-output devices. A basic processor includes
    a normal mode and two simultaneous modes for input-output operations.
    A third I/0 simultaneous mode and a communication mode are optional.
    Printers, card punches and interrogating typewriters are completely
    Internal number system                  Binary coded decimal
    Decimal digits/word                     10
    Character oriented, word capabilities
    Decimal digits/instruction              10
    Instructions/word                        1
    Instructions decoded                    61
    Arithmetic system                       Boolean arithmetic
    Optional high-speed arithmetic unit provides fixed and floating point
    Instruction type                        Two address
    Number range
        Limited by size of memory selected. 
    Instruction word format
    |    1      |      1      |    4      |   4       |
    | Operation | N Character | A Address | B Address |
    N Character specifies an I/0 device, symbol or count;
    or, in combination with the OP Code, an operation.
    Automatic built-in subroutines
    Several operation codes have the effect of a subroutine, i.e.
    Translate by Table provides conversion from one bit structure to
    another; Transfer by Count to Edit edits data for printing.
    Automatic coding
    Automatic coding includes FORTRAN, COBOL-61 Extended with Report
    Writer and an Assembly System.
    A variety of general-purpose service programs are provided. The
    Operating System includes a File Control Processor which handles input-
    output processing and the Executive Control System which controls the
    physical environment.

BRL 1964, RCA 3301 REALCOM, starting page 0231

    Other programs provided include PERT, an "Oscillating" 
    sort and merge system, utility programs such as memory dump, 
    tape copy, tape compare, test data distribution,
    peripheral conversion programs and all required PLT 
    maintenance routines. RCA 301 programs are also accommodated.
    Registers and B-Boxes
    There are ten basic registers plus 50 four-character 
    locations in Micro Magnetic Memory (MMM) for register storage.
    Included in MMM are three index registers and 
    accompanying increment registers.
           Incl. Stor. Access    Excl. Stor. Access
           Microsec              Microsec
    Add        9.75                1.75
    Mutt      34.63               26.63
    Div       58.00               50.00
    Construction (Arithmetic unit only)
    The quantity of transistors, diodes and magnetic cores used 
    in the arithmetic unit depend on the particular unit used.
    Arithmetic mode          Serial (Standard)
        Parallel high-speed arithmetic unit, 
        and for indexing and incrementing index registers.
    Above times assume 8-character fixed point fields 
    with high speed arithmetic unit. Sample internal speeds (incl.
    instruction access time) are: 
       Transfer 10 char. word: 5.75 microseconds; 
       Compare 10 char. fields: 6.25 to 42.25 microseconds 
         (left to right compare with termination upon inequality).
    Timing             Asynchronous
    Operation          Concurrent
                      No. of        No. of       Access
      Medium          Words         Digits       Microsec
    Magnetic Core     4,000 -      40,000 -        1.75
                     16,000       160,000
    Micro-Magnetic       50           200          0.25
    Data Disk File             22,000,000 -  100,000 Avg.
     Medium                        Speed
    Punched Cards   Model 324     900 cards/min
                    Model 329   1,470 cards/min
    50 or 81 column cards are photo-electrically read 
        in binary or translate mode.
    Paper Tape                   100, 500, or 1,000 chars/see
    Can accomodate 5, 6, 7 or 8 channel tape. 
    Magnetic Tape
      All input devices are operated in a simultaneous mode 
      allowing compute to occur during the read.
    Medium                   Speed
    Printer, Model 333      1,000 lines/min (120 chars/line)
    Printer, Model 335      1,000 lines/min (160 chars/line)
    Card Punch                300 cards/min
      80 col/card in binary or translate mode.
    Paper Tape Punch         100 or 300 chars/min
    Features include the punching of 5, 7, or 8 channel tape.
    Console Typewriter       924 chars/min
        Accommodates each RCA 3301 character
    Magnetic Tape
      Printer and card punch are completely buffered. 
      Transfer to the printer and card punch control occurs 
   in a simultaneous mode at the rate of 4 microseconds 
   or 36 microseconds/character respectively. 
     All output occurs in a simultaneous mode
   with compute concurrently proceeding in the Normal Mode.
   In addition to normal input-output devices, four 
   real-time or communications devices are available 
   in the RCA 3301 Realcom System.
    The Interrogating Typewriter is a completely buffered 
    input-output device for remote inquiry. Inquiry messages may be
    entered from a distance of up to 2,000 feet from the 
    Computer. Output is typed at up to 924 characters/minute. Eight
    Interrogating Typewriters are permitted in an RCA 3301 System.
    The Communications Control permits long distance communication between an RCA 3301 and other computers or remote
    terminals via telephone lines.

Magetic Tape Model Nr: 581 582 681 3485
24 Units can be connected Units 24 24 24 24
No. or chars/linear inch Chars/inch 333 667 800 200,556,800
Channels or tracks on the tape Tracks/tap 16 16 16 8
Blank tape separating each record Inches 0.34 0.54 1.1 0.75
Tape speed Inches/sec 100 100 150 150
Transfer rate Chars/sec 33,333 66,667 120,000 30,000, 83,400, 120,000
Start time Millisec 3.5 3.5 5.3 3.0
Stop time Millisec - - 2.0 2.0 2.0
Average time for experienced operator to change reel Seconds 30- 45 30- 45 30 - 45 30 - 45
Physical properties of tape
Width Inches 0.75 0.75 0.75 0.50
Length of reel Feet 2,400 2,400 2,400 2,400
Composition Mylar Mylar Mylar Mylar
Tape stop time is required for read-after write check; other tape slow down time is available for computation. The RCA 3301 Realcom is basically a character machine with word capabilities. Instructions are accessed by word, and internal data manipulation may be either word or character as programmed. Four models of the Data Disk File are available on the 3301. Model 1 with 22,118,400 characters; Model 2 with 44,236,800 characters; Model 3 with 66,355,200 characters; and Model 4, with 88,473,600 characters. Up to six Model 4 disk files will have a capacity of over 530,000,000 characters. Disk Characteristics: 9 data zones of 128 tracks each per disk surface. Each track sores 1,600 sevenbit characters and is divided into ten 160-charact r sectors. In one movement all the access arms of a file are positioned so that all of the read- write heads are over the same track in each zone. Because of this feature, the file is not limited to the data on a single disk. When the heads are positioned over one of the 128 tracks in each zone, there are from 108 (model 1) to 432 (Model 4) full tracks available with no additional mechanical movement. Once initiated track selection proceeds independently of other computer processing.

BRL 1964, RCA 3301 REALCOM, starting page 0232

    Extensive checks are conducted at key points within the system to
    insure accurate reliable operations. Parity is checked whenever
    information is transferred within the system. Other error conditions
    detected include the use of an invalid operation code, addressing
    beyond the confines of high-speed memory, arithmetic overflow, and
    divisor error.
    Input-output operations are effectively controlled with respect to the
    devices being busy or inoperable, or incorrect parity being read or
    When the Realcom hardware detects a malfunction, an indicator is set
    and control is automatically transferred to the Executive system via a
    priority interrupt. Software then analyzes the condition, effects an
    automatic tape re-read or re-write when indicated, and communicates to
    the operator if required.
    Site preparation requirements. A 208 volt, 60 cycle/second, single-
    phase, four-wire power system is required.
    Number produced to date             1
    Number in current operation         1
    Time required for delivery         11 months
    MODEL       TYPICAL                          MONTHLY
    3303      BASIC PROCESSOR               $   9,800
     3361-3   Memory Increment                  2,500
    3378-21   CMC                                 680
    6025-21   Interface Unit                      100
    6002-11   Telegraph Buffer                    300
     6071     Communications Rack                  60
     6072     Buffer Frames (10)                  300
    6080      Power Supply                        100
     581      Tapes (6) 33KC                    3,300
    3383-6    Dual Tape Channel                   400
     324,     Card Reader & Control               660
    333, 3333 On-Line Printer & Control         1,575
                                             $ 19,775
    3303      BASIC PROCESSOR                 $ 9,800
    582       Tapes (8) 66KC                    7,00O
    3383-12   Dial Tape Channel                   450
    324, 3329 Card Reader & Control               660
    333, 3333 On-Line Printer & Control         1,575
                                             $ 19,485
    3303      BASIC PROCESSOR                  $9,800
    582      Tapes (6) 66KC                     5,250
    3383-6   Dual Tape Channel                    400
    303   Satellite (301)                       1,750
    330     Card Reader/Punch and Control       1,130
    333, 316-1 On-Line Printer & Control          850
    582    Tapes (2) 66Kc                       1,750
    394-1 & 2 Tape Adapters                     1,376
                                             $ 22,306
              RENTAL RATES
    MODEL     TYPICAL                         MONTHLY
     NR.      SCIENTIFIC SYSTEM                RENTAL
    3304      BASIC PROCESSOR                $ 11,675
    404, 3361-3 Memory Increment                2,500
    581       Tapes (5) 33KC                    3,150
    324, 3329    Card Reader & Control            660
    3436, 3336   Card Punch & Control           1,600
    333, 3333    On-Line Printer & Control      1,575
                                             $ 21,160
    Personnel requirements vary in accordance with thecomplexity of the
    problem and the configuration of the equipment.
    RCA offers, without charge to the user, courses in the application and
    use of the RCA 3301 Realcom System. RCA provides training of personnel
    or user representatives in systems analysis courses, programming
    courses, special purpose courses, and operators courses. A continuous
    education program is also provided.
    The machine design of the 3301 Realcom system utilizes techniques
    tested and proven in the RCA 301 and RCA 601 Computers. Logic design
    of the RCA 3301 Realcom was enhanced by use of RCA 501 computer
    programs to check and validate design requirements.
    A single system can handle communications, realtime, random access,
    scientific and serial data processing requirements.
    Building block concept on a functional basis is standard in both
    hardware and software systems.
    Software design permits changes in computer usage without the
    requirement of user reprogramming.
    Production and real-time programs can operate simultaneously.
    Automatic priority interrupt feature facilitates simultaneous program
    operation and error detection and recovery.
    Variable item and record length with word capabilities.
    Indirect addressing and indexing are standard. Multiply and divide,
    and editing features are standard.
    Transfer between the disk file and the high-speed memory occurs in a
    simultaneous mode at 32,000 characters/second.
    The Communications Mode Control permits on-line data input-output
    transmission between the RCA 3301 computer and various remote devices
    utilizing the standard communications line facilities. The CMC permits
    the servicing of 20, 40, 60, 80, 100, 120,140 or 160 buffer-terminated
    communication lines. An additional mode of simultaneity permits the
    transfer of data either way between the Processor and the lines to be
    time-shared with other input-output and compute operations.
    The Data Exchange Control permits long distance communicate with
    either another RCA 3301 or an RCA 301. Data transmission may be in
    either direction, one direction, one direction at a time. Two DXC's
    may be included in an RCA 3301 System. Data transfer rate is up to
    266,666 characters/second.

BRL 1964, RCA 3301 REALCOM, starting page 0233

    Diagram by Radio Corporation of America

BRL 1964, RECOMP III, starting page 0234

    Autonetics Div of North American Aviation
    Photo by Autonetics Division
    General purpose computing.
    Internal number system           Binary
    Binary digits/word              40 including sign
    Binary digits/instruction       20
    Instructions/word                2
    Instructions decoded            54
     Includes 4 optional floating point instructions.
    Arithmetic system               Fixed and floating point
     Floating point is optional and fixed point is standard.
    Instruction type               One address
    Number range      - (239-1) to + (239-1)
    Instruction word format

    |  1   |  6   |    6    |    6    |    1      |   1   |  6  |    6    |   6     |   1       |
    | Sign | OP   | Channel | Sector  | 1/2       | Index | OP  | Channel | Sector  | 1/2       |
    |      | Code | Address | Address | Word      |       |Code | Address | Address | Word      |
    |      |      |         |         | Indicator |       |     |         |         | Indicator |
    |         1st Instruction                     |           2d Instruction                    |

    Automatic built-in subroutines
       Boostrap Loading Subroutine
       Diagnostic Program
    Automatic coding
       FORTRAN Compiler
       RIP 3000 Interpreter
       G-15 Intercom Translator
    Registers and B-Boxes
       A Register - Accumulator
       B Register - Number Register
       G Register - Location and Index Register
       R Register - Lower Accumulator
       Z Register - Instruction Register
       Two 8 word fast access registers
BRL 1964, RECOMP III, starting page 0235
           Incl. Stor. Access    Excl. Stor. Access
           Microseconds          Microseconds
           Fixed Point           Fixed Pt.          Floating Pt.
    Add      9,440 (Avg)           540              1,100
    Mult    19,700 (Avg)        10,800             12,400
    Div     20,000 (Avg)        11,100             12,200
    Construction (Arithmetic unit only)
     Transistors and Condenser-Diodes
    Arithmetic mode    Serial
    Timing             Asynchronous
    Operation          Sequential
                      No. of      Average Access
     Medium           Words       Microsec
    Magnetic Disk    4,096          8,900
    Magnetic Disk       16          2,160
    Medium          Speed           Remarks
    Typewriter     Manual           Flexowriter
    Paper Tape     10 chars/sec     Flexowriter
    Paper Tape    600 chars/sec     Facit Punch
     (Stops on character)
    Punched Card   20 columns/sec
    (Skips columns at 80 columns/second).
    Handles 5, 6, 7, or 8 channel paper tapes.
    Handles 4 input devices without modification.
    Medium        Speed               Remarks
    Typewriter      10 chars/sec     Flexowriter
    Paper Tape      10 chars/sec     Flexowriter
    Paper Tape     150 chars/sec     Facit Punch
    Punched Card    20 columns/sec
    Point Plotter
      X axis       200 increments/sec (Max)
      Y axis       200 increments/sec (max)
      Z axis        10 operations/sec (Max)
    Handles 4 output devices without modification
       Single operation mode.
       Permanently recorded diagnostic program. Optional: 
       Recomp Systems Tester - Displays states of all flip-flops,
       provides for marginal voltage test and logic checking.
    Power, computer          0.40 KVA 0.9 pf 3.5A at 115 V. AC
    Volume, computer        31.0   cu ft
    Area, computer          12.5   sq ft
    Room size required    Normal desk area
    Weight, computer       395    lbs
    Number produced to date        40
    Number in current operation    30
    The system may be operated by office or engineering
    personnel with a minimum of training.
    Small size, low cost, versatile. Simplicity of programing and
    aeration. Large library of available programs. SPARC III
    Program for Automatic Circuit Design Analysis.

BRL 1964, RPC 4000, starting page 0236
    RPC 4000
    (Formerly Royal McBee Corp. RPC 4000)
    Librascope Div., General Precision Inc.

    Photo by Librascope Div., General Precision Inc.
    General purpose, simple to operate, low cost computer and data
    processor with large internal memory.
    Internal number system      Binary
    Binary digits/word          32
    Binary digits/instruction    5
    Instructions/word           One
    Instructions decoded        36 + Variation
    Arithmetic system           Fixed point
     Floating point             Programmed
    Instruction type            Two-address
    Number range                + 1 to - 1
    Instruction word format
    | 0   4 | 5         17 | 18     30 |     31     |
    | Order | Data Address | Next Add. | Index Flag |
    Automatic coding
     Act IV
    Registers and B-Boxes
      1 Index
      2 Accumulators, 1 of which extends to 8 words in length.
    Word recirculating
           Incl. Stor. Access  Excl. Stor. Access
           Microsec            Microsec
    Add     1,040                 260
    Mult   17,420              16,380
    Div    17,420              16,380
     A multiply by 10 is accomplished in 260 micro sec.
    Construction (Arithmetic unit only)
     Vacuum-tubes                    0
     Transistors                   197
     Condenser-diodes              540
     Magnetic cores                  0
    Arithmetic mode             Serial
    Timing                 Synchronous
    Operation               Sequential

BRL 1964, RPC 4000, starting page 0237
                  No. of    No. of Bin.   Aver. not Optimum
    Medium        Words     Digits/Word   Access Microsec
    Drum          8,008       32            8,320
    Medium                Speed
    Paper Tape     500 chars/sec
    Manual          10 chars/sec
     Medium                Speed
    Paper Tape     300 chars/sec
    Typewriter      12 chars/sec
    Type                  Quantity
    Tubes                    0
    Diodes               4,500
    Transistors            500
    Magnetic Cores           0
    Parity on input.
    Power, computer        1 Kw 1 KVA     1 pf
    Air conditioner                  None
    Volume, computer             60 cu ft
    Area, computer               15 sq ft
    Floor loading            33 lbs/sq ft
    Weight, computer              500 lb
    No special site preparation required.
    Number produced to date                 115
    Number in current operation             104
    Number on order                           4
    Time required for delivery              1 to 2 months
    One operator is required for an 8-hour shift.
    Training is made available by the manufacturer to the user.
    Mainframe        95% uptime (average)
    Peripheral      90%o uptime (average)

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