UNIVAC 422 COMPUTER

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Throughout the country a growing number of colleges, universities, and vocational schools are developing regularly scheduled courses in data processing. Moreover, business and industry spend large sums of money and valuable time training their personnel prior to conversion to electronic data processing. But most of these training courses lack one prime factor-a computer system for practical instruction.

Univac concluded that an inexpensive laboratory tool was needed to allow students to practice computer techniques learned in the classroom.

Engineered to complement your classroom instruction .,. The UNIVAC 422 Computer is a compact, transportable computer that incorporates many of the basic features of much larger processors solid-state components, magnetic core storage, parallel operations, and a powerful repertoire of instructions. In addition to its use as a training device, the 422 Computer can be used by programmers as a program logic tester.

AND THE UNIVAC 422 COMPUTER IS AVAILABLE AT A FRACTION OF THE COST OF LARGER SYSTEMS...

The UNIVAC 422 has been carefully designed to meet the needs of both classroom and laboratory.

For classroom use, a group of students can easily observe the registers and controls of the machine, and can learn proper operating procedures. All logical elements are exposed, permitting the instructor to demonstrate the functions of the individual circuits. In the laboratory, two or three students may be assigned to the same machine at one time, yielding a high-use factor and increasing the amount of actual machine time given to each student.

TESTED AND ACCEPTED... The forerunner of the UNIVAC 422 Computer has been tested and accepted by the military services where electronic data processing plays an extremely vital role. Military personnel found that the use of this computer greatly reduced training time and increased student comprehension of data processing and electronics maintenance. Now an advanced and improved version of that trainer is commercially available to reduce training time and costs.

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FEATURES

POWER REQUIREMENTS

60 cycle, 115 VAC, 500 watts. (approx.)

Sixty-four instructions provide the programmer with all of the tools necessary to build his program. These instructions allow for maximum programming flexibility, and include arithmetic functions such as add, . subtract, multiply, divide, and complement; logical functions such as transfer, shift, store, jump, and selective stop; and input-output functions for communicating with the typewriter and the paper tape reader and punch. The repertoire is flexible enough to allow the preparation of elementary programs in the areas of scientific computation, process control, business problems, and information retrieval

TOTAL COMPUTER CAPABILITY
The UNIVAC 422 Computer does not limit the student to a part of a computer, or a pseudo-computer, but affords practice on a complete data processing system. At the same time, the 422 Computer is simple enough to be understood by the beginner in a short period of time; this is an important factor in maintaining high interest levels.

ON THE SPOT MAINTENANCE
On-the-spot maintenance by the owner or user is made practical because the UNIVAC 422 Computer can be furnished with spare circuit cards. A circuit card testing device is built into the front panel of the 422 Computer. Easy accessibility, test probes, and standard logic cards make it simple to demonstrate and practice maintenance procedures.

The impact of electronic data processing has been felt in many varied areas of American life; in business and industry; in government and national defense; in medicine, transportation science and education, In order to increase knowledge in this still relatively new medium of data handling, UNIVAC has engineered and built the 422 Computer, an inexpensive, compact, binary computer for use as a training device in the data processing classroom. Its unusual power and versatility make it capable of duplicating many of the characteristics and operations of large scale systems.

We are Searching for  a UNIVAC 422 to complement the other computer training devices we have in the Computation Collection at the museum!

Please drop us a line if  you know the location of a unit or any parts or manuals associated with it!

UNIVAC 422 COMPUTER REFERENCE MANUAL

                                              Page No.

Figure 1 - BLOCK DIAGRAM                             12 
Figure 2 - INSTRUCTION FORMAT                    12 
Figure 3  - INSTRUCTION WORD FORMAT        12 

LIST OF TABLES 
                                            Page No.

Table 1  - REPERTOIRE OF INSTRUCTIONS      -  13

INTRODUCTION

The UNIVAC® 422 Computer is a general-purpose, solid-state, parallel binary computer de-

signed for indoctrinating new personnel in the principles of digital data processing. Since the logic and circuits of the computer are similar to those of large scale commercial computers, civilian and industrial installations, including colleges, universities, vocational schools and data-processing centers, will find the 422 Computer extremely useful.

Major features of the 422 Computer include the following: (1) Word Length - 15 bits

(2) Arithmetic - paralle 1, one's complement, subtractive (3) Memory - magnetic core

·512 words

- cycle time 6 microseconds

- access time, 1.25 microseconds (4) Program - internally stored

(5) Repertoire - 16 basic single address instructions which can be modified by designators to produce 64 different instructions

(6) Instruction Time - add, 12 microseconds

- multiply 30-60 microseconds - divide 57 microseconds

(7) Basic Clock Speed - 4 megacycles, 4 phase

(8) Power Requirements - 60 cycle, 115 V AC, 500 watts (Approx)

(9) Peripheral Equipment - Typewriter unit with paper tape reader and punch

(10) Input/Output - one pair of I/O channels

(11) Over-all Computer Size - 9 in. x 26 in. x 54 in.

(12) Over-all Typewriter Unit Size - 18 in. x 18 x 12 in. (Approx)

GENERAL

INTRODUCTION

The UNIVAC® 422 Computer is a general-purpose, solid-state, parallel binary computer de-

signed for indoctrinating new personnel in the principles of digital data processing. Since the logic and circuits of the computer are similar to those of large scale commercial computers, civilian and industrial installations, including colleges, universities, vocational schools and

data-processing centers, will find the 422 Computer extremely useful.

Major features of the 422 Computer include the following: (1) Word Length - 15 bits

(2) Arithmetic - paralle 1, one's complement, subtractive (3) Memory - magnetic core

·512 words

- cycle time 6 microseconds

- access time, 1.25 microseconds (4) Program - internally stored

(5) Repertoire - 16 basic single address instructions which can be modified by designators to produce 64 different instructions

(6) Instruction Time - add, 12 microseconds

- multiply 30-60 microseconds - divide 57 microseconds

(7) Basic Clock Speed - 4 megacycles, 4 phase

(8) Power Requirements - 60 cycle, 115 V AC, 500 watts (Approx)

(9) Peripheral Equipment - Typewriter unit with paper tape reader and punch

(10) Input/Output - one pair of I/O channels

(11) Over-all Computer Size - 9 in. x 26 in. x 54 in.

(12) Over-all Typewriter Unit Size - 18 in. x 18 x 12 in. (Approx)

GENERAL

The 422 Computer emphasizes rapid communication with external devices and is governed primarily by the speed of the equipment connected to it.

Single address instructions are employed, with instruction words of 15 bits.

Internal storage of the 422 consists of a 512-word ferrite core memory. Control and Arithmetic Sections of the computer have access to the Storage Section. A complete cycle for storage of a IS-bit word from one of the sections requires six microseconds.

Arithmetic and logical operations are performed in the parallel binary mode. In most instances, the result of an operation appears in a IS-bit accumulator register (A). Arithmetic is one's complement subtractive with a modulus (2¹⁵ -1).

Computer operation is controlled by a stored program capable of self-modification. The program instruction contains a 4-bit function code, a 9-bit instruction operand, and 2 bits reserved for instruction modification. Execution modifiers provide for address incrementation, operand interpretation, branch-point designation, and function code modification. For some instructions, the operand may be increased by the amount contained in the index register (B). The operand specified by the execution address can be interpreted as a IS-bit quantity with or without sign

2

extension. The next sequential program step may be skipped, depending upon the contents of the B register. The contents of the accumulator (A) or logical function (Q) register can also cause a program jump to a remote address.

Communication between the 422 Computer and its associated external equipment is accomplished under program control. A communication path is established by a sequence of request and response signals between external equipment and computer. Such signals may originate in either the computer or the external devices.

One pair of Input/Output channels is provided with the computer. This pair of I/O channels provides six parallel lines which are employed by the Typewriter Unit. The transfer rate of input or output data over a given channel is determined by the program, and the speed of the paper tape reader and typewriter.

The Input/Output channels carry EXTERNAL FUNCTION WORDS as well as data words to external equipment. These specify the function desired of the external device. An EXTERNAL FUNCTION WORD to the paper tape unit, for example, may specify "Enable Paper Tape Reader".

The computer is housed in two sections, which are assembled into a single unit that is 9 inches deep, 26 inches high, 54 inches wide. One chassis of logic modules is vertically oriented within the unit. Logic modules consist of printed circuit cards which plug into the chassis. Maintenance test points are readily accessible on each of the chassis. The computer also contains a built-in card tester.

The 422 computer operates on 115-volt, 60-cycle power. Total power consumed by the computer and Typewriter unit is approx. 500 watts. Under normal conditions no air conditioning or water cooling is required. Therefore, the computer can be installed wherever a convenience outlet is available.

The high instruction execution rate gives the 422 Computer a data-processing capability far greater than that possessed by regular training devices. The user can easily exploit this capability by using the 422 Computer to solve a wide variety of problems.

The 422 Computer has been carefully designed to meet the needs of both classroom and laboratory. For classroom use, a group of students can easily observe the registers and controls of the machine, and can learn proper operating procedures. All logical elements are exposed, permitting the instructor to demonstrate the functions of the individual circuits. In the laboratory, two or three students may be assigned to the same machine at one time, yielding a high-use factor and increasing the amount of actual machine time given to each student.

The repertoire of instructions is designed to cover the widest possible spectrum of programming orientation, including program indexing (B-boxing). Beginning with simple arithmetic problems, the trainee programmer can progress through programs of increasingly greater difficulty. The physical construction of the 422 Computer is particularly suited to the training of computer maintenance engineers and technicians. All sections of the computer are readily accessible

for the development of skill in maintenance and troubleshooting procedures.

A simplified block diagram of the 422 Computer appears in Figure 1. For explanatory purposes, The 422 Computer may be considered as comprised of four major sections: Control,

Arithmetic, Storage, and Input/Output. The operation of the various sections is discussed in the following paragraphs.

CONTROL SECTION

The Control Section consists of those registers and circuits necessary to procure, modify, and execute instructions of the program. The instruction word consists of 15 bits. The upper 6 bits are called the "instruction", and the lower 9 bits make up the "operand".

The F register receives the 6-bit instruction and is called the Program Control Register.

The instruction remains in F while it is being executed.

The 6-bit instruction is composed of f, k, and b designators (see Figure 2). The 4-bit f designator determines what instruction is being performed: add, subtract, shift, etc. The k designator is used to detect the source of the operand, and the b designator is used in conjunction with the

B register for indexing purposes. The k designator and b designator are sometimes combined to form the j designator. This enables the computer to have a larger, more versatile repertoire of instructions.

The lower-order 9 bits of the instruction word enter the X register and make up the operand, or

the address of the operand, of the instruction being executed. These bits can be modified or "indexed" by the B register, which is controlled by the b designator.

In addition to the F register, the S,P ,and K registers are a part of the control section.

S - A 9-bit memory address register. Its main function is the translation of the memory address for the current instruction so that its contents can be obtained for processing.

P - A 9-bit program address register that holds the address of the current instruction in memory.

During operation, the contents of the P register are normally incremented by one in order to ad_~ vance the program to the next sequential instruction.

Kl and K2 - Four-bit registers employed by the shift, multiply, and divide instructions. The contents of K 1 and K2 are sampled to determine when the instruction has been completed. ARITHMETIC SECTION

The Arithmetic Section is that part of the computer which performs numeric and logical calculations. Though greatly simplified, Figure 1 shows the important components of the Arithmetic Section: A, D, Q, and X registers and the "add" network.

The A register (15 bits) may be thought of, for programming purposes, as a conventional accumulator. Because of the logic employed, however, the A register does not feed directly into the add network, but only receives the output of that network.

The Add operation is typical of the relationship between the A, D, and X registers. The augend and addend are initially contained in the A and D registers. As the Add instruction is performed, the contents of the A register are transmitted to the X register. This action makes the X register the main rank of the add network; the D register serves as a second rank. The sum is formed in parallel by the add network and placed in the A register.

The Q register (15 bits) receives one-half of the double-length product from a multiply instruction, and receives the quotient from a divide instruction. The contents of both A and Q may

be shifted left or right, individually or as one double-length, 30-bit word. The Q register is also employed as the communication register to external equipment during Input/Output instructions.

STORAG E SECTION

The Storage Section consists of the main memory stack, address translation logic, transfer register (2), and control circuits.

The memory, constructed of modular arrays of ferrite cores, has a capacity of 512 words of 15 bits each, is coincident-current driven, and is addressed via the address translator. Content

of the referenced address is read into the 15-bit 2 register.

The memory operates in the destructive read-out mode, and the time required to execute the

read/restore cycle is six microseconds.

INPUT /OUTPUT SECTION

The Input/Output Section includes a pair of I/O channels and control circuits used by the 422

Computer for communicating with the Typewriter unit. All communications into or out of the Typewriter unit must pass through the lower 6 bits of the Q register. The same 6 bits are used when sending the External Function to the Typewriter unit.

Because the Input/Output Section is simplified, all data transmission and inputs are under control of the main program.

The Operator and Maintenance Control Panel includes: (1) indicator lamps that display a detailed report of the internal status of the computer, and (2) controls that allow varied, manually governed operations. It is not necessary to monitor the panel during normal operation.

Each register, except the B register and K register, is represented on the control panel.

The registers are shown by a row of display lamps, each of which indicates the contents of a corresponding register stage.

The control panel is provided with manual controls that permit the following special modes of operation:

-1.  

(1) (2) (3) (4)

 

 

Execution of one master clock phase for each depression of a switch

Execution of one sequence of a program instruction for each depression of a switch Execution of one program instruction for each depression of a switch

Operation that is normal or high speed

0.  

4

The panel includes a set of Jump and Stop switches that can, in normal computer operation, govern the execution of a select-jump instruction. If stop conditions are satisfied, the computer stops and an indicator is lighted to show that the select stop condition has been honored. In the case of the select-jump condition, the computer will honor the jump only if the Select Jump switch is engaged, and the proper instruction is executed.

The Master Clear switch is a spring-return toggle that is used to clear all registers and control designators to zero. This clearing action does not include the main storage.

This portion of the technical notes presents the instruction repertoire (see Table 1) of the

-1.  

f k b

J ()

RNI

 

 

= Function code designator

= Operand interpretation designator = Index designator

= Function code modifier and branch designator

= "contents of"

= Read next instruction

0.  

L(Y) (Q) = Bit-by-bit multiplication of Y nand Qn. Logical Product

1.  

y (y) Y

Yn

(Y)

A

D

Q S

P F

x z

 

 

= Operand designator. Low-order 9 bits of the instruction word

= Indicates the operand is located at the memory address specified by y

= Indicates the operand is y plus b modification. (In the repertoire of instructions,

it means "the operand" regardless of its source.) = nth bit of the contents of memory address y

= Indicates the operand is located at the memory address specifIed by y plus

b modification

= The A register (IS-bit arithmetic register) = nth bit of the contents of the A register

= The B or index register. Located at memory address 0

= The D register (IS-bit arithmetic register) = The Q register (IS-bit arithmetic register) = Memory Address Register (9 bits)

= The P or Program Address Register (9 bits) = The F or Program Control Register (6 bits)

= The X or exchange register (IS-bit arithmetic register) = A IS-bit non-addressable memory exchange register

2.