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Programming an HP-15C (2013)

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Re: Programming an HP-15C (2013)

#41

Post by mschaef »

lmilcin wrote: post #32
mschaef wrote: post #13

Earlier quoted context omitted.

I have a 42S emulator running on my iPhone, but it really isn't the same as being able to press physical keys on a hardware device. One of the charms of these devices was that they were built to last. ie: the keys were injection molded with two colors of plastic so they wouldn't wear down. So, while I still have a couple of working HP's from the 80's, I've been through a dozen or more mobile phones in about the same…

I have actual 42S. The physical device lasts very well but the LCD fades out as it gets older. Right now mine does not have enough contrast to read it looking at it directly. You need to look it from downward angle and in perfect light. Other than that this is the best calculator ever made.

At the time I bought my 48SX, I remember briefly considering a 42S. I had a lot of fun with the 48, but in retrospect, I'd have gotten more use out of the 42.

(But what I really regret is not having bought a 16C.)

Re: Programming an HP-15C (2013)

#42

Post by RedNifre »

Oh, yeah, I wrote a Brainfuck interpreter for those https://steemit.com/programming/@michaelzinn/babbage-s-diffe...

I also did a C64 BASIC compiler in Idris for it, if you have a copy with over 800 lines of program memory you can play HAMURABI on it: https://forum.swissmicros.com/viewtopic.php?f=23&t=2193

I strongly recommend that calculator, it's a great programming toy.

Re: Programming an HP-15C (2013)

#43

Post by 0culus »

I have both the HP15C and two HP16Cs, though I am not old enough to have bought one new. :o) Truly awesome calculators, even if they are a bit slow sometimes. The form factor of the Voyagers is amazingly perfect; in fact the ratio of the length to width is approximately the Golden Ratio if I recall.

I use mine regularly as I prefer a tactile instrument. Plus the mental challenge of implementing programs in a constrained environment is invigorating.

Re: Programming an HP-15C (2013)

#45

Post by mschaef »

acqq wrote: post #26
mschaef wrote: post #11

Earlier quoted context omitted.

> Wow that sounds a lot more complicated than the one I had, HP 42S, Yeah... the 42S derives from the earlier 41 series, and the 41 series was the first to use alphanumeric symbolic names for programming commands. Prior to that, there was always a very direct correlation between the button you pressed on the keyboard and the way the command was encoded in memory. (Which made sense given how resource limited the earli…

I consider HP-28S a work of art. The programming language can be described as an effective mixture of Forth, Lisp and even APL and J. The memory was also very efficiently used, the HP-28S had whole 32K! (not a little for that time). And all that with 4-bit CPU (!) which worked for a very long time on very small batteries. https://en.wikipedia.org/wiki/HP-28_series

> I consider HP-28S a work of art.

I'd extend that to the whole HP calculator lineup through about 1994 or 95.

There are a lot of aspects I could single out, but William Kahan's involvement in their numerical algorithms is a particular standout for me. They wanted high quality numerics out of battery powered 1970's era micro-electronics, so they brought Dr. Kahan in to design the algorithms necessary for the task.

(Dr. Kahan is also noteworthy for his involvement in IEEE-754, which is still the standard for floating point today.)

Serious, serious engineering went into these calculators.

Re: Programming an HP-15C (2013)

#46

Post by 0culus »

mschaef wrote: post #45
acqq wrote: post #26

Earlier quoted context omitted.

I consider HP-28S a work of art. The programming language can be described as an effective mixture of Forth, Lisp and even APL and J. The memory was also very efficiently used, the HP-28S had whole 32K! (not a little for that time). And all that with 4-bit CPU (!) which worked for a very long time on very small batteries. https://en.wikipedia.org/wiki/HP-28_series

> I consider HP-28S a work of art. I'd extend that to the whole HP calculator lineup through about 1994 or 95. There are a lot of aspects I could single out, but William Kahan's involvement in their numerical algorithms is a particular standout for me. They wanted high quality numerics out of battery powered 1970's era micro-electronics, so they brought Dr. Kahan in to design the algorithms necessary for the task. (D…

What would you say is the final model that "has it"? Besides my vintage HPs (HP15C, 2xHP16C, HP45) I also have the 50g and the modern 35S. For me, the 50g's lack of a proper ENTER key ruins it. I'm sort of on the lookout for a nice 48 series to replace it for that reason. The 35S at least has a proper ENTER.

Re: Programming an HP-15C (2013)

#47

Post by golem14 »

smabie wrote: post #40
golem14 wrote: post #38

Earlier quoted context omitted.

The HP store shows many of their remaining 7 (!) calculator models out of stock quite often. I'm not taking any bets on how long HP is going to make any calculators at all. I feel sad every time I visit their store... They already stopped making any kind of graphing calculator, apparently.

Hp prime?

No longer on their (hp) store. Still can get unsold inventory on eg amazon

Re: Programming an HP-15C (2013)

#48

Post by s_T_e_v_o »

I still have mine and the user manual sits on a shelf in my basement. I bought mine in a private deal from a guy whose father was a distributor. Cost me $110 in 1984. It allowed me to invert a 4x4 matrix, thereby earning me an A in my power engineering class. I programmed a sinc function to the amazement of my linear systems instructor. And I programmed complex multiplication and division routines. This was pretty cutting edge back in the day, long before mathcad.

Re: Programming an HP-15C (2013)

#49

Post by watmough »

cameldrv wrote: post #14

Related: it’s been sad to see the HP48 emulators bitrotting. m48 is no longer available on the App Store, and I can’t find anything that works anymore for the Mac.

Gosh. I got lucky that the m48 from my 6s restored successfully to my 11 pro. Love that software.

Re: Programming an HP-15C (2013)

#50

Post by SkyMarshal »

golem14 wrote: post #38
jonsen wrote: post #21

Earlier quoted context omitted.

HP still makes a decent HP-15-like calculator: https://en.m.wikipedia.org/wiki/HP_35s

The HP store shows many of their remaining 7 (!) calculator models out of stock quite often. I'm not taking any bets on how long HP is going to make any calculators at all. I feel sad every time I visit their store... They already stopped making any kind of graphing calculator, apparently.

HP ported their calculators to iPhone and Android apps. Most people who want an HP calc probably just use those now instead, except for the few who want the tactile feel of calculator buttons.
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