🚀 go-pugleaf

Sorry if this is a bit off-topic, but...

In <PHR.92Sep30185509@napa.telebit.com> phr@telebit.com writes:

>...
>  One advantage of the Bible is that, at least until recent times, carrying
>  one wouldn't draw suspicion to the spy.  (Carrying a Hagelin machine
>  would be pretty incriminating).  As a modern day alternative, I've
>  often thought the No Such Agency could do the following:
>  
>     - write encryption/decryption code that runs in an embedded
>       micro of the kind found in calculators.
>  
>     - go to favorite defense contractor that also makes calculators
>       (e.g. TI), and say "we want you to make a new model of simple,
>       consumer calculator, priced so lots of people will buy them
>       (here's some $$$ to make it profitable), and by the way, when
>       the user types this undocumented 20-keystroke sequence, it should
>       run this code that we'll supply (from previous step).

This reminds me of my first scientific pocket calculator I used in
high school. (It was manufactured by Casio but I know the way TI
calculators suck and I surely can imagine a TI with such features too
;-)

It was a (then) highly pouplar model called fx85, which was slightly
cheaper than the fx100, which looked exactly the same, except that a
third (blue) layer of key definitions (apart from first (black) and
second (brown) functions) was missing from the 85. Knowing a bit about
mathematics you would have recognized the blue functions as
statistical functions. 

Both of the calculators had an INV key (some sort of a shift) and a
MODE key (for switching from degrees to radians). Pressing BOTH of
them would result in switching the machine into SD (statistical) mode,
in which the third function layer was in effect and, of course, some
keys had total different meanings.

The manual of the 85 stated that [paraphrased] 'some wrong input may
cause an ERROR sign to appear, in which case you should turn the
machine off and on again.' It turned out that the condition for
getting an ERROR was exactly INV-MODE, and the same could be used to
turn the ERROR off again.

Now, some people had the 100 model, and quickly we found out that
except for the nasty ERROR display instead of SD, the statistical
functions did work as well on the 85. The two models had the same CPU,
only the displays and key labels were different.

Now don't tell me that there are no pocket calculators with surprising
undocumented features :-)

MfG,
        Olaf
-- 
    o     Olaf Titz - comp.sc.student - univ of karlsruhe - germany
 _ /<_    s_titz@iravcl.ira.uka.de - uknf@dkauni2.bitnet - praetorius@irc
(_)>(_)   +49-721-60439 - did i forget something?
Wichtig ist, was hinten rauskommt. - Helmut Kohl