John W. Kennedy wrote:
A) There were a number of completely different 70x/70x0 lines, and, B)
the Whirlwind was done by MIT; I cannot at this moment find any evidence
that IBM was involved at all, although IBM later used parts of the
abandoned Whirlwind II specs for the noncommercial AN/FSQ-7. Development
of the 701 was certainly stimulated by the Korean War, but it and its
successors were never intended specifically for government use.
Considering the price and strategic nature of the technology, you pretty
much had to be a government agency or contractor thereof to get one in
their heyday. But yes, it was not government-specific. I imagine if some
rich movie star or musician had wanted one, they could have plunked down
the x.x million and IBM would have built them one. But they did suck at
synthesizing music.
That’s simply wrong. There was no 707, and the 7070 /was/ the follow-on
to the 650, as any history of IBM’s pre-360 computers will tell you. As
with the 701->704, 702->705, and 1401->1410 transitions, the machines
were not compatible, but general concepts and formats were. In this
case, the 7070 retained the basic 650 word architecture of ten decimal
digits plus a sign, and continued to use two-digit op-codes and
four-digit addresses. But the four digits that the 650 used for the
next-instruction address were replaced by two digits to select an index
register and two digits to select a subfield of the data word.
As an aside, I worked at IBM during the transition from the 7000 series
to System\360. There was never a 707, and wouldn’t have been because of
the airliner. The 704 was originally called the 703 but someone else
grabbed that number and so IBM moved to 704, forcing the follow-on to
the 702 into 705.
More notes from that period: in addition to FORTRAN, IBM developed a
language called COMTRAN for business programming. It never caught on,
though, mostly because Grace Murray Hopper and Univac and the Feds put
all their weight behind COBOL.
No, the 7070, 7072, and 7074 were follow-ons to it.
The 7070 was kind of a half-breed business and scientific machine. Yes,
its architecture looked like a 650, but it had a real FORTRAN compiler,
tape drives and all the other mainframe peripherals.
The IBM pre-360 commercial lines (-> incompatible; => compatible):
The main scientific line
701->704=>709=>7090=>7094=>7094 II
|
.->7040=>7044
(The 7040 line was a cheaper subset of the 7090 line. It did /not/
derive directly from the 704, as some have incorrectly concluded from
the number.)
The 709 was a short-lived beast. The architecture of the 709 and 7090
were almost identical, and IIRC there were less than a dozen 709s built.
The 709 was a tube machine and the 7090 was a transistor machine, so
most folks just kept their 704s going until they could get a 7090.
By the way, IIRC the 701 did not have hardware floating point or index
registers. It was essentially a 36-bit version of the Von Neumann IAS
machines like ILLIAC I, ORDVAC, JOHNNIAC, etc. Both floating point
arithmetic and index registers appeared in the 704. The 709/7090 added
I/O channels and indirect addressing, but not much else.
Budget scientific and real-time.
1620=>1710
(The 1710 was a 1620 with command-and-control extras. There was also a
one-off 1720.)
This niche later was occupied by the 1130 and 1800, respectively.
(The 1440 was an almost-compatible cheaper version of the 1401; the only
incompatibility was in the handling of punched cards and printing. The
1410 was an incompatible upward extension of the line; machine code was
different, but carefully written assembler code could be portable. Two
more systems in the line were the 1240 and the 1420, which were
essentially 1401s with magnetic-ink reader/sorters in the same chassis.)
The 7010 was pretty much upward compatible from the 1410.
Budget general-purpose machines.
650->7070=>7072=>7074
I wouldn’t call any 7000-series mainframe a “budget” system. The
hardware, power, cooling, weight and size were quite similar. They all
had “SMS” card logic and magnetic core memories, although some of the
core memories were air cooled and some were oil cooled. The closest
thing to a “budget mainframe” before System\360 was probably the 7010.