John wrote:
"Why do you care about non-programmability? You don't
*have* to program a programmable calculator!"
I concur with this observation, I thought the same
when I read the original post. Any programmable RPN can
be used as if it wasn't at all, so what's the point ?
About the only reason I can fathom for the absolute need
of a non-programmable RPN calculator is if programmables
are forbidden at some exam.
Else, the minimal LCD programmable is possibly the
HP-10C, which has only 8 bytes of program memory to begin
with [they only expand to about 70 if you do key in some
program]. Also, it's programmability is so minimal that
most HP-25 worthwhile programs simply don't fit in.
However, getting an HP-10C is much easier said than
done, so the next minimally-programmable, affordable LCD
model must be the HP-12C. This model has also only 8 bytes
of program memory initially.
If you want it for use as an everyday RPN,
non-programmable calculator, I would honestly recommend using an
inexpensive, easy to get HP-12C. It has lots of storage
registers, it's classy and good looking, Singapore and USA
models are solid and well built [unlike Chinese ones],
and has all functions you would need, save trigonometrics.
And if you do need trigonometrics, you can use its
program memory to store a trigonometrics package
permanently. It's exactly what I use, always at hand.