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This memorandum was propared by tho 

Sub-Panel on General Purpose Analytic Equipment 

of the NSASAB on 7 March 1955 

1. The Sub-Panel on General Purpose Analytic Equipment has met 

twice for periods of several days at the Agency to review the development program of the Agency in this area and to t?""J and formulate some 

conunents and recommendations which may be helpful in cxbending our 

progress along these lines. 

2. At the February meeting considerable emphasis l'll'S.B placed on 

the present state of the art and on the potentiality of o.chieving a 

very high speed ~rithmetic and logical unit in the milli-microsccond 

range. Dr. vonNeumann and others strongly urged an intensive research 

program in speed of components of this sort aimed at determining 

ult:ima.te limits of the physical phenomena which are helpful to very 

high spoed devices 1 such as the effective grain size and other physica1 

limits. It was pointed out in particular while there are other groups 

in the government interested in this area that research of this type 

will not get itself automatically done and that the Agency appears to 

be the logical organization to initiate work in this area and that 

support might be secured from other sections of the Defense Department 

and the J\.It~C if such a program were undertaken. 

3. A general concept for a General Purpose Analytic Machine was 

set forth as a programmcd-3cquencc-control machine incorporating 

_)eclassified and approved for €ONFIDENTIA:L elease by NSA on 11-15-2013 

Jursuantto E .0. 13526 
nncillfa.ry units co.rrying out specific cryptologic operations or proccssos. In order to meet tho l·ride ve.ricty of rcquirc.r.ionts in ve.rious 

typos of work in the Agcnc;y it 'lrm.s felt tha.t such a machine should 

have the capacity of modifying its instructions by a technique such 

as micro-progrrurnning l"rhich will permit the construct ion of new instructions which the machine ca.n carry out after it.s completion and while 

it is in use. This buuld also permit the creating of complete instructions on what arc essentially short high speed. sub-routines which can 

be called into operation by a single instruction and applied repeatedly 

by a mechanism such as the 1103 1 s repeat inst:tUction. 

4. A third requ:i.romcnt in the machine would be the development of 

some way of introducinf:; .,. parallelism in the operation of various 

portions of tho maclunc so that tho quantity of work produced can 

approximate in some special cases thn.t of special purpose analytic 

machines such as the comparators or the sled type machine. 

5. It is felt that for thi::; general area 0£ machine operation a 

basically different logicc:i.l organization from that of the customary 

electronic computer may bo preferable. One point in particular in 

which there seems to be general ug1·eement was that essentially all data 

processing and w~nipulntion involves two streams of data and that the 

machine should be organized so tho.t WC>rk con be effectively carried 

out on tho basis from input through proccssine; to output nnd the 

o.rith:r.i.otic unit bo connected between tho two streams and perhaps 

folloued b:r a comparison rlcvi.co between the two strcu.ms. It is also 

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felt that because of' the nature of tho work the machine ahould be 

fundrunentally based on character-at-a-time operation \d.th variable 

word, message, .and record length so that a single instruction can 

call for the complete processing of an area of data corresponding 

to any one of these classes. 

6. One very important general requirement is that special 

attention be given to the simplicity of prograrmning the machino so 

that more one-time jobs can be undertaken by the progra.nmers and 

even by the analysts as they cncolUlter situations where a machine 

run may bo useful. 

7. In view of the status of t~e digital computer art at the 

present time as indicated by machines in use, it appears quite 

reasonable to set up standards for llUl.@letic tape input and output 

operations of 501 000 characters per second; for an internal electronic character handling rate of one million characters per secondJ 

and for magnetic drwn reading of 2501000 characters per second. 

These basic character rates can all be modified by paralleling to 

secure more favorable ratios between tho various classes of data 

storage. 

s. In accordance with the discussions led by Dr. vonNeumann 

we should certainly use the £nstest possible speed in the central 

analytic unit e.nd work out the necessary mechanism for combining 

this high speed unit with the slower memories which are all that 

are available nt the present time. 

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9. A discussion submitted ut t:1c li::.st meeting lrlth Hr. Snyder 

and Er. Lathrown conccrnine the F1::.rmcr Project indicates thut this 

pror,rc:.m lncorpara.tos much of this thinking ::!.nd io Pppro~chine a 

point i.rhcrc some def lnito dcsi~n decisions can be made loo.ding to 

the starting of a minimum system to which addltiona.l units can be 

added as developed. There is, however, a basic difference in tha.t 

the Fe.rmcr system considers the individual analytic units a.a special 

mo.chines which can be operated independently with separate input and 

output. The computer ~Tith its progro.mmed sequence control is a vital 

but not essential one of the ma.chines in the system. This in turn 

implies that the various ma.chine units in the system have logical 

programming ability and that control would be passed from one machine 

to the next as it completed its work on some particular data. For 

instance, a minimum system ltU.r,ht consist of input and output units, 

a modular arithmetic nnd D. scorine unit, t>.nd this rnti.chinc would be 

useful without the computer and ito ovcr.:i.11 program control. 

10. Because of a similarity between the Farmer Program and 

suggestions made by Panel l·Iembcrs in regard to the General Purpose 

Analytic Machine, it is strongly recommended that additional analytic 

and engineering effort be devoted to defining the elements ot the 

Fanner System and to establishing design standards for the system 

and review of possible logical organizations of the computer a"'ld ot 

the auxiliary units such as comparators, the recognition units, 

rotor analogs, etc., and in particular, that the set of instruc4 

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tions particularly those which are peculiar to this work- ba 

formulated for discussion and comparison with the mo~t advanced 

digital computar machines. 

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