23 Jan
2011
23 Jan
'11
1:16 p.m.
When was this stored-program (in the normal sense)
system added? Before or after other stored-program machines such as EDSAC Manchester Mk1,
etc?
Good question. Conventional wisdom says it happened in 1948, which is
the same year as the Manchester computer. Wikipedia (FWIW) says the
Manchester computer first operated on June 21. I don't know when in
1948 ENIAC got its own stored-program ability.
But .... here's something interesting to ruffle the Manchester fans'
feathers: http://www.columbia.edu/acis/history/acm-meeting.jpg. It's a
memo stating that, at the first meeting of the ACM in 1947, the
unfinished EDVAC computer was working and demonstrated. EDVAC was a
stored-program machine too. So if the memo's claims are true, then it's
possible this function was show pre-Manchester.
(Personally I think that argument is pointless. It's not like the
Manchester team didn't do any testing; I have to assume that the June 21
day of running its first program was not actually the first day it was
turned on and tested. Still, the memo linked above is talking about
March 1947, which is a long time before June 1948. So it just might
hold water.)
there were several projects in electronics magazines
over here in the 1970s to make a pocket calculator 'programamble'. Typically they
ahad a small RAM, the otuptus of which were used to simulate keypresses on the calcualtor.
The better ones had some kind of conditional (often dtecting the -ve sign or the position
of the decimal point in the display. My view is that the calcuaotr with this kuldge is a
stored-program comptuer, without it, it isn;'t. So going ban to ENIAC, it may well
have been modified int oa computer at some point, but this doesn't mean it was a
computer at the start.
I disagree about the need for a program to be of the stored variety for
the machine to be a computer. What's important is that the program can
be accessed at electronic speeds vs. electromechanical speeds.
To the ABC advocates, I ask, "How did your machine access its program
... oh wait, I almost forgot, it didn't have one." :)
Ergo a calculator -- and not even an all-electronic one at that.