|Re: hp 71b|
Message #7 Posted by Ex-PPC member on 25 Feb 2003, 5:19 a.m.,
in response to message #1 by Joe Edwards
Hi Joe, glad you liked my former posts on the HP-71B.
As for your request for info or opinions, I'll tell you
the HP-71B is the one HP machine I use most of the time,
even today. I do have all the others (41's, 42's, 32's,
15C's, etc), but the one I grab to do *anything* be it
at home or out of it, is the HP-71B.
My HP-71B is fitted with nearly 210 Kb RAM, the Math ROM,
the HP-IL ROM, the Forth/Assembler ROM, and the Card
Reader, and no other HP calculator can touch it, in sheer
power, ease of use, manufacture quality and versatility.
Why ? Let's see:
Manufacture quality: it is *extremely* robust, strong,
durable. It has real HP keys, molded (not painted),
with the usual HP colours and quality, as found in the
Voyager series, for example, not cheap plastic, painted,
garish-colours affairs. Those keys can stand any
use and abuse, indoors and outdoors with ease. Matter
of fact, my HP-71B is the only calculator/computer I
can trust to work reliably under extremely cold and
humid conditions, mountains in winter, for instance.
After nearly 20 years, it still looks and works like new.
Memory: while a 32s has some 0.3 Kb or so, an HP-41CX
can have up to some 6 or 7 Kb, and a 42S can be fitted
with as much as 32 Kb, you can fit up to 512 Kb RAM/ROM
combination in a 71B. I've seen machines with up to
400+ Kb, and mine has nearly 210 Kb. That's more than
enough for most programming needs, even those involving
data collection (surveying, geophysical engineering),
and you can handle really large systems of equations
and matrices with that much memory. Compared to that,
a 42S simply does not deliver the goods.
Expandability: unlike the almost non-I/O 32S/42S, you
can fit dozens and dozens of devices to an HP-71B, via
the HP-IL module. This ROM can handle up to three IL
loops, with scores of devices on each one, and can
transmit data in excess of 5,000 bytes/second. You can
use digital tape drives, floppy disks, control other
HP-71Bs or even HP-41Cs, and using the HP-IL/HP-IB
interface card, you can even access and control files
on a PC !! The HP-IL ROM features some 50 keywords
(which extend BASIC, written in assembly, of course)
which allow you to do most anything I/O-related you
may want. Just ask Tony Duell ! :-) Matther of fact
its HP-IL controller capabilities are so good that the
HP-71B has been used and is probably still used inside
HP as a controller for their expensive digital measurement
devices (multimeters, oscilloscopes, etc).
If that wasn't enough, you can use the attached card
reader to write/read programs and data without any
HP-IL mass storage devices in sight.
Ease of use: The HP-71B features one of the best BASIC
dialects ever. It comes with more that 240 keywords,
and features such advanced capabilities as a whole
file system which allows multiple files in RAM, multiline
user defined functions, named subprograms, recursivity,
passing parameters by value and reference, user-selectable
precision for numeric arrays, two-dimensional matrices,
strings, 12-digit IEEE precision with NaNs', infinities,
and gradual underflows with denormalized exponents,
programmable timers that can turn off and on the
machine or interrupt execution at specified intervals,
As such, it's extremely easy to write programs using it,
even very complex ones, and what's better, you *can*
understand and modify your own programs months or years
after you wrote them. I guess that no matter how much
we like or love RPN, it's far too cryptic when compared
to English-like, BASIC statements, not to mention RPL.
User-expandability: the HP-71B allows you to program it
in at least four languages: BASIC (native), RPN (HP-41C
translator, runs some 7 times faster than the real
thing), FORTH (runs 6-10 times faster than BASIC) and
Assembler (full machine speed).
In this regard the HP-71B is almost unique in that it
allows the user to add his/her own BASIC keywords to
the already existing ones, in assembly, undistinguishable
in use, appearance and speed, from the built-in ones.
For instance, I've created a LEX (Language EXtension)
file that adds some 40 very powerful keywords to the
BASIC. Once created, you can share this file with any
other HP-71B, use the keywords in your programs, etc.
Also, most ROMs add their own keywords, such as the
50+ added by the HP-IL ROM, the 85+ added by the Math
ROM, etc. That why you'll find yourself with hundreds
and hundreds of extremely powerful, assembly-language
high-level BASIC keywords at your command.
Open: Full documentation is available for the HP-71B,
including the complete, documented, commented listings
for the 64 Kb operating system, with thousand of
supported entry points exhaustively documented for use
in your own assembly-language routines. You can use
those entry points as subroutines in your own keywords,
and you can even modify the way the built-in keywords
work, by means of intercepting polls, so further
customizing even the built-in BASIC language to your
I could go on, and on, and on, I haven't mentioned
the incredible CALC mode, the 15-level command stack,
the user-definable keyboard and character set, the
graphic, dot-addressable display, but the summary is clear:
there is no other HP machine which can touch the 71B. Some
may have more memory, some may be smaller, some may be
faster, none is more rugged, none is more extensible,
none has all those features to such a high degree in the same, very machine.
Of course, it isn't perfect, it could use
at larger display, for instance, but then nothing is.
As for use, I use it daily, from balancing my checkbook
to keeping personal data, to playing what-if with my IRS
data (far from a non-secure PC environment), to gathering
geophysical data high on a mountain, at -20. I would trust
no other HP calculator/computer to perform flawlessly and
reliably under such environmental circumstances.