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<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>When I first learned
to program in 1964 we used an IBM 1620, fondly known</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>as CADET (Can't Add,
Doesn't Even Try). It had 20,000 memory cells, each</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>of which stored one
<EM>decimal</EM> digit. Words were delimited by a flag bit in
the</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>most significant
digit -- i.e. they were variable length. Since there were
no</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>integrated circuits
then, the whole desk-sized machine, complete with blinking</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>lights, console
switches, and a built-in IBM Executive electric typewriter
for</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>small amounts of
input and output, was made with individual transistors.
My</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>ex could type faster
than that machine, especially with a Selectric, but this</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>was before the
Selectric too.</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>For larger amounts
of input or output one of course used the read-punch unit.</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>You typed your
Fortran program on a keypunch, went to the machine, set the</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>switches, read in a
deck with the Fortran compiler, reset the switches, read in</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>your program and it
punched out the object code on a deck of cards. If you
</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>needed any
subroutines (sine, exp, etc.) they were on a separate deck you
read</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>in and it punched
out the necessary code. Finally you took your compiled
deck</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>from the punch side,
reset the switches, and read it in and got your output
off</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>the
typewriter. If you had a lot of output, you punched it to a deck of cards
and</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>took them over to
the listing machine, put in an appropriate pegboard to get
the</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>formatting you
wanted, and printed out the deck.</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>The variable word
length was very useful for calculating Fibonacci numbers to</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>1000's of
digits. Incidentally, 3/5/08 last month is a Fibonacci date, the
last</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>one for about 5
years till 5/8/13. After that it's 8/13/21 and that's it for
this</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2>century.</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial size=2>Please do not bend,
fold, staple or mutilate these cards.</FONT></SPAN></DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=875381207-04042008><FONT face=Arial
size=2>Bob</FONT></SPAN></DIV></BODY></HTML>