🚀 go-pugleaf

In article <1989Dec24....@smsc.sony.com>, dce@smsc (David Elliott) writes:
]I looked at some of the data, and things like envelope rates of '>'
]and '&' showed up.  In other words, there is no check in the program
]for values that are too high.  You can't increment or decrement out
]of range, but random data isn't repaired.

I had the good fortune to acquire an HP-45 calculator free of charge
(seems the place my father worked never bothered to get calculators
fixed when they broke, they just left them in a drawer.  The problem
with every single one of them was loose connections between the system
board (that's right, inside a pocket calculator) and the keyboard card.
H-P actually put some real effort into those things.  They took me about
10 minutes to fix).  Connoiseurs of the '45 are aware of the
undocumented stopwatch feature (resolution to .01 second, 10 "splits",
and time/decimal conversion, but the clock frequency was wrong; it was
something like 14% slow, but I forget the exact conversion constant).
Before I learned from an ad in an old Byte magazine about how to invoke
it properly, I found it quite by accident:  the battery connectors were
dirty, and sometimes I'd momentarily lose power.  The glitches this
caused put the calculator in a variety of random states, one of which
was this stopwatch.

Another interesting thing that sometimes happened was that I'd get a
wholly incomprehensible display, with a variety of numbbers separated by
blanks on the display.  When I hit a certain key, a new set of numbers
would be displayed.  I never did learn what that was about, but I always
suspected that it was some sort of microcode debugger/stepper left in
the machine for some reason or other (the display obviously followed a
pattern, but I never figured it out).  I always wondered if the machine
was programmable somehow or other by means of this.  It would have been
a nice machine, since the H-P was much faster than the other traditional
machines of the (early 1980's) day, the TI 55 and 57.

I haven't used the 45 in a while (I now have a 10C).  It was a really
nice machine, though.  Really amazing for something that came out around
1973 or 1974.
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