Grace Brewster Hopper

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At present, the multiplication time for the computer is 3 milliseconds, and the sddition time is 80 microseconds. These present times are partly due to safety factor delays which have been built into the arithmetic control circuitry

by means of mono-stable fllp-flops. Wlth the present arithmetic control, a multiplication time of 1 millisecond and an addition tlme of 50 microseconds seems feasible.

M A C H I N E AIDS TO C O D I N G By

Naval Research Coding process

of

for

A problem

be expressed

of several forms of tation

types logical

the

volving variables, direct

code of

the

to be computed

result

language.

out

difficulty.

arranged

in

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cases

checking

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use 17

necessary ~rocess, auxiliary

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ed Into

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digital

E a r l Y. I s a a c Laboratory, Washington

in

clerical

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ary

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advantages.

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permits the coder to think

positions

occupied

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the

c o m b i n a t i o n s of the e l e m e n t a r y a r i t h m e t i c

punches

control

and logical o p e r a t i o n s

reproducer

in terms of functions

that are c o m p l e x

of the machine.

that

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that

than that p e r m i t t e d by the basic machine.

appropriate

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deck.

the r e p l a c e m e n t for

the

system

in is

the

by t h e

machine

now u n d e r

Naval Research

development

Laboratory

to

a single-address

the

For

purely

system

will

permit

the

coder

in each

instruction,

written

dundant

dictionary,

up to six

for

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the

subroutine

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control

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producer

only

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form and with

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previously.

left

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deck while

in

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the in-

information cards

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instruction

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in-

is

card i s

in terms

of the com-

translatlon

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and sub-

form the

processes

of

a careful

analysis

or

subroutine.

blanks

decks

in

puter but with symbols still from a re-

word

constants

placed

the first card

of the e l e m e n t a r y o p e r a t i o n s

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coded

is

c o n t a i n i n g a set of i n s t r u c t i o n s

and

sets

subroutine

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read.

of

and re-

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the

from the g a n g - p u n c h e d columns

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by s u b r o u t i n e s

into

deck.

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into a p p r o p r i a t e

structure,

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symbols

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two s t e p s :

translation

step

is held.

transfer

(1)

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the

selectors

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deck

of

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place

is p u n c h e d

of the s u b r o u t i n e

results

of

subroutine

of the s u b r o u t i n e

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the

feed

into

in

contain

As each instruction card

arguments

a n IBM s o r t e r

and takes

the

operations

using

designation

arguments

feed,

formation

the

computer,

arithmetic

read

decks

read

timing

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arguments.

passes under the r e a d i n g brushes

A

perform

for

this

at

the

positions

punch feed.

equivalent

terminology.

translation NAREC.

the

of the coder's e x p r e s s i o n

complex operation

structure

is

subroutine

and the

punch the

by t h e

not

itself

any advantage

using

the

in re-

stead

of

for

use.

pattern

computer the

performed

step

as

described

can obviously

described

above.

can determine

elementary

this

whether

purpose

machinery

perOnly

would be gained for

of

by in-

now i n

COMPUTER AIDS TO CODE CHECKING By I r a C. D i e h m N a t i o n a l B u r e a u of S t a n d a r d s , W a s h i n g t o n W h e n a complex r o u t i n e is t r i e d on a c o m p u t e r for the first time, it is seldom f o u n d to be free from error. The t r e n d t o w a r d a u t o m a t i c p e r f o r m a n c e of the c l e r i c a l p a r t s of the coding p r o c e s s should r e d u c e the n u m b e r of coding errors. This m e c h a n i z a t i o n of c o d i n g is the subject of several

p a p e r s at this conference. Nevertheless, a significant a m o u n t of v a l u a b l e c o m p u t e r time w i l l c o n t i n u e to be d e v o t e d to the search for oodlng e~cors. Careful proofreading and clerical c h e c k i n g are o b v i o u s but important 19