␈↓↓␈↓ α.A DISPLAY TERMINAL SYSTEM FOR THE COMPUTER SCIENCE DEPARTMENT


␈↓␈↓ α(This␈α⊂ is␈α⊂a␈α⊂plan␈α⊂to␈α⊂equip␈α⊂the␈α⊂Computer             ␈↓ εx␈↓␈↓ πX3.␈α
 Each␈α terminal␈α
 should␈α
 be␈αcapable␈α
of
␈↓Science␈αDepartment␈α
with␈αa␈αsystem␈α
of␈αkeyboard     ␈↓ εx␈↓displaying␈α∀at␈α∀least␈α∃half␈α∀a␈α∀page␈α∃of␈α∀arbitrary
␈↓and␈αdisplay␈αterminals␈αfor␈αuse␈α in␈α teaching␈α and  ␈↓ εx␈↓character␈α~ sets␈α~ and␈α~ also␈α~ graphics.␈α→  The
␈↓research.␈α∃  The␈α∃ terminal␈α∃ system␈α∃ will␈α∃make    ␈↓ εx␈↓character␈α∂  sets␈α∂  used␈α∂  in␈α∂ programming␈α∞ and
␈↓accessible␈α∂to␈α∂department␈α∂faculty␈α⊂and␈α∂graduate   ␈↓ εx␈↓in␈α
 mathematics␈α∞ have␈α
proliferated␈α
to␈α∞the␈α
point
␈↓students␈αfrom␈α
their␈αoffices␈α
the␈α IBM␈α 360/67␈α
 in  ␈↓ εx␈↓where␈α⊂allowing␈α⊂each␈α⊂user␈α⊂to␈α⊂ have␈α⊂ whatever
␈↓the␈α∂ Computation␈α∂ Center,␈α∞ the␈α∂ PDP-10␈α∂in␈α∞the    ␈↓ εx␈↓characters␈α~ he␈α~wants␈α→is␈α~the␈α~only␈α→solution
␈↓Artificial␈α∀Intelligence␈α∪Laboratory,␈α∀and␈α∪through␈↓ εx␈↓compatible␈α!with␈α!the␈α goal␈α!of␈α!using␈α any
␈↓the␈α≠PDP-10␈α≠any␈α≠computers␈α≠on␈α≠the␈α≠ARPA             ␈↓ εx␈↓computers␈αthat␈αare␈αavailable␈αto␈αour␈αfaculty␈αand
␈↓network␈α&that␈α% they␈α& may␈α& have␈α% made             ␈↓ εx␈↓students.
␈↓arrangements␈α to␈α use.␈α  This␈α includes,␈α for
␈↓example,␈αthe␈αILLIAC␈α4␈αat␈αAmes␈αResearch␈αCenter.    ␈↓ εx␈↓␈↓ πX4.␈α
Printing␈α
facilities␈α
compatible␈α
with␈αthe
␈↓Connections␈α∪to␈α∪ other␈α∪campus␈α∪computers␈α∩can      ␈↓ εx␈↓above␈α≠should␈α≠ also␈α≠be␈α≠ available␈α≤but␈α≠not
␈↓also␈α
be␈α
arranged.                            ␈↓ εx␈↓necessarily␈αwith␈αeach␈αterminal.␈α In␈αfact,␈αthere␈αis
                                           ␈↓ εx␈↓no␈α∪present␈α∪ way␈α∩ of␈α∪ making␈α∪ such␈α∩ facilities
␈↓␈↓ α(In␈α⊂our␈α⊂opinion,␈α⊂such␈α⊂a␈α⊂terminal␈α⊂system           ␈↓ εx␈↓available␈α≤ to␈α≤ each␈α≤terminal␈α≤ but␈α≠ suitable
␈↓together␈α
with␈α
suitable␈αhard␈α
copy␈α
output␈α in␈α
 the  ␈↓ εx␈↓public␈α∩ printers␈α⊃can␈α∩be␈α⊃had,␈α∩for␈α∩example␈α⊃the
␈↓most␈α≤ important␈α≤ laboratory␈α≤ and␈α≤ teaching     ␈↓ εx␈↓Xerox␈α
XGP.␈α
The␈α
cost␈α
of␈α
 adding␈α
 such␈α
 a␈α
 printer
␈↓facility␈α
 that␈α
a␈α
computer␈α
science␈α
department␈α
can ␈↓ εx␈↓has␈α
 not␈α∞ yet␈α
 been␈α
determined,␈α∞but␈α
there␈α∞is␈α
a
␈↓have.␈α The␈αinterests␈αof␈αthe␈αfaculty␈αand␈αstudents  ␈↓ εx␈↓strong␈α⊗demand␈α⊗for␈α⊗it,␈α⊗and␈α⊗its␈α⊗cost␈α⊗will␈α⊗be
␈↓are␈α∃too␈α∃varied␈α∃to␈α∃be␈α∃satisfied␈α∃by␈α∃any␈α∀one          ␈↓ εx␈↓included␈α
in␈α
a␈α
future␈α
version␈α
of␈α
the␈α
plan.
␈↓computer␈α
 since␈α
 no␈α
 one␈α
 computer␈α
 will␈α have
␈↓all␈α∩ the␈α∩hardware␈α⊃and␈α∩software␈α∩facilities␈α⊃that   ␈↓ εx␈↓␈↓ πXThe␈α
scheme␈α
proposed␈α
has␈α
the␈αfollowing
␈↓are␈α
of␈α
research␈α
or␈α
teaching␈α
interest.           ␈↓ εx␈↓characteristics:

␈↓␈↓ α(The␈α_plan␈α_we␈α↔are␈α_now␈α_proposing␈α↔is                 ␈↓ εx␈↓␈↓ πX1.␈α∀The␈α∪display␈α∀image␈α∪for␈α∀each␈α∪active
␈↓based␈α∩in␈α∩ part␈α∩ on␈α∩ a␈α∩ study␈α∩made␈α∪ by␈α∩John         ␈↓ εx␈↓user␈α⊃ is␈α⊃ stored␈α⊃ as␈α⊃ a␈α⊃512x512␈α⊃raster␈α⊃in␈α⊂an
␈↓McCarthy␈α∞at␈α∞M.I.T.␈α
in␈α∞fall␈α∞1972␈α
in␈α∞support␈α∞of␈α
a     ␈↓ εx␈↓integrated␈α
circuit␈α
read-write␈α
memory.
␈↓plan␈α
to␈α∞get␈α
a␈α
terminal␈α∞system␈α
for␈α∞Project␈α
MAC
␈↓and␈α∃the␈α∃Artificial␈α∃Intelligence␈α∃Laboratory.␈α∀ In ␈↓ εx␈↓␈↓ πX2.␈α
 There␈α
are␈α64␈α
terminals,␈α
but␈α
only␈α32
␈↓this␈α⊗ study,␈α⊗ requests␈α⊗ for␈α⊗ proposals␈α∃ were    ␈↓ εx␈↓memories␈αso␈αthat␈αonly␈αhalf␈αof␈αthe␈αterminals␈αcan
␈↓sent␈α
to␈α
leading␈α
firms␈αin␈α
the␈α
display␈α
field␈αand␈α
the  ␈↓ εx␈↓be␈α↔active␈α⊗simultaneously.␈α↔ However,␈α↔ a␈α⊗ low
␈↓replies␈α→ were␈α→ evaluated.␈α→ The␈α~ best␈α→ plan,     ␈↓ εx␈↓duty␈α∂ cycle␈α∂is␈α∂to␈α∂be␈α∂expected␈α∂if␈α∂the␈α∞terminals
␈↓however,␈α→ was␈α→found␈α→to␈α→be␈α~scheme␈α→being           ␈↓ εx␈↓are␈α
in␈α
offices␈α
so␈α
this␈α
is␈α
ok.
␈↓developed␈α∞by␈α∞Peter␈α∞Wiener␈α∞of␈α∞Yale␈α
University,
␈↓and␈α⊃our␈α⊃plan␈α⊃is␈α⊂based␈α⊃ on␈α⊃ the␈α⊃ Yale␈α⊂scheme        ␈↓ εx␈↓␈↓ πX3.␈α∩The␈α∩cost␈α∩to␈α∩add␈α∩a␈α∩terminal␈α∪to␈α∩the
␈↓which␈α
 is␈α
 also␈α
 being␈α
 followed␈α
 by␈α∞ the␈α
 M.I.T. ␈↓ εx␈↓system␈α is␈α about␈α $500,␈αand␈α the␈α cost␈α to␈α add
␈↓Artificial␈α0Intelligence␈α0 Laboratory.␈α/  The    ␈↓ εx␈↓a␈α∞ memory␈α∞ is␈α∂ about␈α∞ $2200␈α∞now,␈α∞but␈α∂a␈α∞large
␈↓Stanford␈α~  Artificial␈α~  Intelligence␈α~Laboratory␈↓ εx␈↓reduction␈αis␈αexpected␈αin␈αless␈αthan␈αtwo␈αyears␈αas
␈↓also␈α∪hopes␈α∪to␈α∪upgrade␈α∪its␈α∪Data␈α∀Disk␈α∪display       ␈↓ εx␈↓4096␈α∞bit␈α∂memory␈α∞chips␈α∞come␈α∂ into␈α∞ production
␈↓system␈α
to␈α
the␈α
new␈α
standard.                    ␈↓ εx␈↓replacing␈α⊂ the␈α⊂ 1024␈α⊂ bit␈α⊂ chips␈α⊂on␈α⊂which␈α⊂the
                                           ␈↓ εx␈↓present␈α
prices␈α
are␈α
based.
␈↓␈↓ α(The␈α∞goals␈α∞that␈α∞we␈α∞want␈α∞to␈α∞achieve␈α
are
␈↓the␈α
following:                              ␈↓ εx␈↓␈↓ πX4.␈α∂The␈α∂system␈α∂is␈α∂controlled␈α∂by␈α∂a␈α∂mini-
                                           ␈↓ εx␈↓computer,␈α⊂say␈α∂a␈α⊂PDP-11,␈α⊂which␈α∂ communicates
␈↓␈↓ α(1.␈α∩A␈α⊃terminal␈α∩in␈α⊃each␈α∩office␈α∩used␈α⊃ by             ␈↓ εx␈↓with␈α→the␈α→host␈α→computers␈α→(initially␈α→the␈α→IBM
␈↓faculty␈α⊂ and␈α⊃ graduate␈α⊂students.␈α⊃This␈α⊂requires  ␈↓ εx␈↓360/67␈α&and␈α&the␈α&PDP-10),␈α&and␈α& writes
␈↓very␈α
low␈α
cost␈α
terminals.                      ␈↓ εx␈↓characters␈α) and␈α) pictures␈α* by␈α) directly
                                           ␈↓ εx␈↓addressing␈α" the␈α" display␈α# memories.␈α" The
␈↓␈↓ α(2.␈α∂ A␈α∂ large␈α∞ terminal␈α∂ facility␈α∂ for␈α∞ the       ␈↓ εx␈↓displays␈α
are␈αmaintained␈α
by␈αa␈α
memory␈α
port␈αthat
␈↓use␈α∪of␈α∩students␈α∪in␈α∩courses.␈α∪About␈α∪ half␈α∩ the      ␈↓ εx␈↓reads␈α~bits␈α~from␈α~the␈α~memories␈α≠ into␈α~ shift
␈↓terminals␈α≡ would␈α≡ be␈α≡ available␈α≡ for␈α≡ this      ␈↓ εx␈↓registers␈α∩and␈α⊃ transmits␈α∩ them␈α∩ together␈α⊃with
␈↓purpose.                                   ␈↓ εx␈↓synchronization␈α∞signals␈α∞through␈α∞a␈α∂video␈α∞switch
                                           ␈↓ εx␈↓to␈α
the␈α
displays␈α
over␈α
coaxial␈α
cable.

␈↓↓␈↓ εH␈↓1␈↓↓␈↓ X



␈↓␈↓ α(5.␈α⊗Each␈α↔display␈α⊗is␈α⊗connected␈α↔to␈α⊗the              ␈↓ εx␈↓␈↓ πX10. Contingencies␈↓ ≠$10K
␈↓central␈α⊃ unit␈α⊃ containing␈α⊃the␈α⊃ memories␈α⊃by␈α⊂an
␈↓individual␈α!cable,␈α!and␈α!the␈α!keyboards␈α!are         ␈↓ εx␈↓␈↓ πX                        TOTAL␈↓ $178K
␈↓connected␈α~to␈α~the␈α~keyboard␈α~multiplexer␈α~by
␈↓twisted␈α∞pair␈α∂unless␈α∞it␈α∞turns␈α∂out␈α∞to␈α∂be␈α∞feasible
␈↓to␈α∞ transmit␈α∞ the␈α∞ keyboard␈α∞signal␈α∞back␈α∞on␈α
the    ␈↓ εx␈↓␈↓ πXNot␈α#included␈α"in␈α#these␈α#costs␈α"are
␈↓same␈α
coaxial␈α
cable␈α
as␈α
is␈α
used␈α
for␈α
the␈α
video.       ␈↓ εx␈↓engineering␈α≤which␈α≤we␈α≠hope␈α≤ to␈α≤do␈α≠ with
                                           ␈↓ εx␈↓volunteer␈α$labor␈α#and␈α$wiring␈α$costs.␈α# The
␈↓␈↓ α(6.␈α∨The␈α∨video␈α∨switch␈α∨is␈α∨a␈α∨32x64                   ␈↓ εx␈↓necessary␈α⊗programming␈α⊗will␈α⊗ also␈α⊗ be␈α∃ done
␈↓electronic␈α∞crossbar.␈α∞ It␈α∞ will␈α
be␈α∞ a␈α∞ copy␈α∞ of␈α
 a  ␈↓ εx␈↓within␈α  the␈α  Computer␈α
  Science␈α  Department.
␈↓unit␈α∂ now␈α⊂ in␈α∂ use␈α⊂in␈α∂the␈α⊂Artificial␈α∂Intelligence ␈↓ εx␈↓Maintenance␈α∞ of␈α
 the␈α∞system␈α
should␈α∞cost␈α
about
␈↓Laboratory's␈α
display␈α
system.                 ␈↓ εx␈↓$5000␈α∃per␈α∃year␈α∃counting␈α∃student␈α∃labor␈α∀and
                                           ␈↓ εx␈↓parts␈α
costs.
␈↓␈↓ α(7.␈α
In␈α
the␈α
initial␈α
version␈α
of␈α
the␈α
system␈α
 all
␈↓characters␈α_ and␈α_vectors␈α_ are␈α→ produced␈α_by       ␈↓ εx␈↓␈↓ πXPerhaps␈α→$50K␈α→of␈α_the␈α→costs␈α→can␈α_be
␈↓software␈α⊃in␈α⊃the␈α⊃mini-computer.␈α⊃ A␈α⊃PDP-11/45     ␈↓ εx␈↓obtained␈α∃from␈α⊗projects.␈α∃ The␈α⊗AI␈α∃ Laboratory
␈↓will␈αtake␈α150␈αmicroseconds␈α
in␈αthe␈αworst␈αcase␈α
to    ␈↓ εx␈↓should␈α
 pay␈α
 for␈α its␈α
 connection␈α
and␈α
the␈αcost␈α
of
␈↓write␈α a␈α character.␈α If␈α the␈αhost␈α
computers␈αcan  ␈↓ εx␈↓the␈α⊗terminals␈α↔used␈α⊗by␈α⊗project␈α↔members␈α⊗on
␈↓support␈αa␈αhigher␈αrate␈αof␈αcharacter␈αwriting␈αthen   ␈↓ εx␈↓campus.␈α≤  With␈α≤ NSF␈α≤ not␈α≥ giving␈α≤facilities
␈↓a␈α
special␈α
character␈α
writer␈α
can␈α
be␈α
added.         ␈↓ εx␈↓grants␈α⊗ any␈α∃ more,␈α⊗ the␈α∃ outlook␈α⊗ from␈α∃that
                                           ␈↓ εx␈↓source␈α⊗is␈α↔not␈α⊗bright.␈α↔ We␈α⊗believe␈α↔that␈α⊗the
␈↓␈↓ α(Here␈α≡are␈α≡the␈α≡components␈α∨of␈α≡ the                 ␈↓ εx␈↓University␈α⊃should␈α⊃pay␈α∩the␈α⊃main␈α⊃ cost␈α∩ as␈α⊃the
␈↓proposed␈α
 system␈α
 and␈α
 their␈α
estimated␈α
costs:   ␈↓ εx␈↓major␈α∂ laboratory␈α∂ instructional␈α⊂ and␈α∂ research
                                           ␈↓ εx␈↓facility␈α
of␈α
the␈α
Department.
␈↓␈↓ α(1. Integrated circuit raster memory␈↓ ¬k$73K
␈↓␈↓ α(complete with buffer registers             ␈↓ εx␈↓␈↓ πXRegrettably,␈α∂there␈α∂are␈α∞a␈α∂few␈α∂costs␈α∞not
␈↓␈↓ α(and power supplies,based on                ␈↓ εx␈↓yet␈α⊃listed␈α⊃above.␈α⊃ The␈α⊃major␈α⊃one␈α⊃is␈α⊃stringing
␈↓␈↓ α(prices paid by Yale and quotes             ␈↓ εx␈↓the␈αcables,␈αand␈αthis␈αhas␈αnot␈αyet␈αbeen␈αexplored.
␈↓␈↓ α(to M.I.T.                                  ␈↓ εx␈↓The␈α⊃cost␈α⊃of␈α⊂the␈α⊃cable␈α⊃itself␈α⊂is␈α⊃not␈α⊃large␈α⊃-␈α⊂4
                                           ␈↓ εx␈↓cents␈αper␈αfoot,␈αbut␈α
the␈αcost␈αof␈αstringing␈α
it␈αmay
␈↓␈↓ α(2. Keyboards␈↓ ¬k$14K                           ␈↓ εx␈↓be␈α⊂significant.␈α⊂ If␈α⊂we␈α⊂figure␈α⊂500␈α⊂foot␈α∂average
␈↓␈↓ α((70 keyboards at $200,                     ␈↓ εx␈↓cable␈α∂length,␈α∂we␈α∂get␈α∂$20␈α∂per␈α∂terminal␈α∂for␈α∞the
␈↓␈↓ α(based on quote by Microswitch)             ␈↓ εx␈↓cable␈α
or␈α$1280␈α
altogether␈α
for␈αthe␈α
bare␈α
cost␈αof
                                           ␈↓ εx␈↓the␈α∞coax.␈α∞ The␈α∞cost␈α
of␈α∞the␈α∞keyboard␈α∞cable␈α
will
␈↓␈↓ α(3. Monitors␈↓ ¬k$14K                            ␈↓ εx␈↓be␈α
less.
␈↓␈↓ α((70 monitors at $200,
␈↓␈↓ α(based on quote by Ball Bros.)              ␈↓ εx␈↓␈↓ πXThe␈α!AI␈α!Lab␈α is␈α!hiring␈α!an␈α expert
                                           ␈↓ εx␈↓programmer␈α and␈α∨digital␈α engineer␈α who␈α∨is
␈↓␈↓ α(4. PDP-11/40 with 16K words␈↓ ¬k$20K            ␈↓ εx␈↓presently␈αbuilding␈α
a␈αYale␈α
type␈αsystem␈α
at␈α M.I.T.
␈↓␈↓ α((D.E.C. published prices)                  ␈↓ εx␈↓He␈α
can␈α
help␈α
with␈α
this␈α
work,␈α
but␈α
he␈α
is␈α
not␈α
free.

␈↓␈↓ α(5. Shift registers and                     ␈↓ εx␈↓␈↓ πXA␈α~recent␈α≠survey␈α~of␈α~offices␈α≠in␈α~the
␈↓␈↓ α(control electronics␈↓ ¬{$5K                     ␈↓ εx␈↓Computer␈α∃Science␈α∃Department␈α∃turned␈α∃up␈α∃57
                                           ␈↓ εx␈↓locations␈α∂where␈α⊂terminals␈α∂would␈α∂be␈α⊂wanted.␈α∂ I
␈↓␈↓ α(6. Video switch␈↓ ¬{$9K                         ␈↓ εx␈↓am␈αnot␈αsure␈αwhether␈αsecretaries␈αwere␈αincluded
␈↓␈↓ α((cost of video switch built by AI Lab)     ␈↓ εx␈↓as␈α≥they␈α≥should␈α≥be␈α≥according␈α≥to␈α≥AI␈α≤Lab
                                           ␈↓ εx␈↓experience.␈α⊗ This␈α⊗suggests␈α⊗that␈α⊗a␈α∃somewhat
␈↓␈↓ α(7. Keyboard multiplexer␈↓ ¬{$8K                 ␈↓ εx␈↓larger␈α⊃system␈α⊂would␈α⊃be␈α⊃wanted␈α⊂if␈α⊃we␈α⊃are␈α⊂to
                                           ␈↓ εx␈↓meet␈α
all␈α
CSD␈αdemand␈α
and␈α
provide␈α
a␈αsubstantial
␈↓␈↓ α(8. Connection to PDP-10␈↓ ¬k$15K                ␈↓ εx␈↓terminal␈α≠room␈α≠(at␈α≠least␈α≠16␈α≤terminals)␈α≠for
                                           ␈↓ εx␈↓students.␈α∂ Therefore,␈α∂we␈α∂recommend␈α∂$200K␈α∂as
␈↓␈↓ α(9. Connection to the IBM 360/67␈↓ ¬k$10K        ␈↓ εx␈↓the␈α∂total␈α∞cost␈α∂of␈α∞the␈α∂project␈α∞not␈α∂counting␈α∞any
␈↓␈↓ α((in addition $300 per month rental         ␈↓ εx␈↓overheads.
␈↓␈↓ α(for IBM hardware is required)

␈↓␈↓ εH2␈↓ X