First(?) HP 33s bug


I realized today while doing my physics homework that my calculator was operating in radians mode, even though the RAD annunciator was not on. I did a bit of research, and realized that if you use the self-test, the LCD screen reverts to its default state (only says RPN), but the calculator does not revert to the default state.

This means that if you are using radians (in my case), which is usually noted by a RAD annunciator, and you use the self test, then your calculator looks like it is in degrees (because there is no RAD annunciator on), but it operates in radians still.

The same holds true for most other annunciators, including bases (it won't say HEX, but it is still in HEX) and user flags (the screen says flags 0-4 are off, but by using FS? they might not be).

I notified HP around 5:00 PM, and have yet to be recieve a response.

Someone test it out to make sure it isn't just mine.



It isn't just your machine. Congratulations, it looks like you've found a genuine bug!


Let's hope the 33s has flash ROM and integrated bluetooth connectivity so that the firmware can be easily upgraded via your cellular phone. Otherwise you will have to get a free replacement unit. I hope that HP already has sold a lot of this c**p, so it won't be too profitable for them. I will always remember the good days when calculators were called 41, 42, 32 and 48 and when they still looked and felt the right way. They were also a bit buggy, but they were great and they had a nice ENTER key ;)


Let me get this straight:

You do not want this calculator to be profitable for HP?

To what end? So they will get out of the calculator business altogether? I don't know if you have thought this through to its possible conclusions (or even some of them). If HP loses money on the 33S I believe you will NOT see any future RPN calculators from them. All the dreamers can then completetly forget about the possibility of a "43S".

Also, you were willing to live with bugs in the "good old days", but this calculator is crap because it has a bug? I don't follow your logic. Why were bugs okay in the past, but today they are sufficient reason to wish ill on the only company left in the world interested in RPN calculators?

Think about it. When the old "classics" are all non-functional or so valuable as collectibles that no one dares use them for their intended purpose (which will happen some day since spare parts are not being manufactured), and HP is not manufacturing RPN calculators, what will we do? I guess we'll all switch to TI Algabraic units; and that will be a sad day, at least for me.

Take care.


PS - As cheap as the 33s is, I'll just keep my "buggy" one and purchase the upgraded one. It's not like they cost $200 or $300 any more, like in the "good old days".


You do not want this calculator to be profitable for HP?

To what end? So they will get out of the calculator business altogether? I don't know if you have thought this through to its possible conclusions (or even some of them). If HP loses money on the
33S I believe you will NOT see any future RPN calculators from them. All the dreamers can then completetly forget about the possibility of a "43S".

I can't speak for Andy, of course, but here's how I see it:

When the 49G came out I hoped it would be a big enough flop that HP would reconsider and go back to making calculators that were more like their older, more successful models. But when the pictures of the 49G+, 48GII and 33S came out (even before the actual units themselves were available), I decided that if this was, indeed, the direction the future HP machines would take, then I'd prefer that they just stopped making calculators altogether. I consider their current products to be an insult, not only to users like myself, but more importantly to the designers of the older models. If I believed there was any reasonable chance that HP might someday make a better calculator then I would feel differently. But the sad truth is that I believe there is almost zero chance that they ever will again make any calculator that I would buy. If the day comes that all of my older calculators no longer work, and I no longer can obtain a working example of the older models from a source like eBay, and no other company has started making a decent RPN model, then I'll just stop using calculators altogether. I'd rather have HP out of the calculator business than continue defiling the memory of their past glorious successes.

In fact, considering that HP has spun off the instrument division (the core of the original Hewlett-Packard), discontinued the HP3000 minicomputer (which I think is the best product HP ever has or ever will produce), and thrown the son of Bill Hewlett off the Board of Directors, it really wouldn't bother me to see the entire company go out of business. I still hope that someone will uncover evidence of illegal activities in the Compaq merger that will result in jail terms for Carly Fiorina and the remaing BoD members.

(Of course, I don't really expect any of that to happen, hence my recent posts about making low-cost introductory RPN models, etc. But that's a case of "making the best of a bad situation," rather than what I'd choose if I could get what I really want. At this point, what I'd really like to see is for HP to go down the tubes and take the personal fortunes of the company officers with it.)


1. Stop using calculators all together. OK. Great idea.

2. "son of Bill Hewlett off the BoD" So? Happens all the time. Nepotism doesn't always work.

3. If the "son of BH" has it in him, he'll start a new company--with the values he holds dear. If not, then that's ok, too---then he wasn't up for the job (either at HP or other) anyway.

Business is business--and rich powerful people make decisions--sometimes bad ones---and they get greedy---sometimes to their detriment.

I agree that there is a sadness about the loss of a great company----but when you get to the point where HP was----it was already gone----then you might as well say "good riddance" and move on.

I was as shocked as the next guy to discover that the RPN calculator was being phased out 2 years ago. But now I am a year older and wiser---and thanks to this forum and others, I now know (a) where and how to get a hold of an RPN device at reasonable cost for a long time to come, (b) that RPN is not the only way and that yes, you can find a reasonable "Algebraic" system and adapt to it, (c) that there are others out there interested in making new RPN devices (even the Aurora 12-c sim is a promising development).

Best regards,


Edited: 4 Mar 2004, 12:15 p.m.


I am not familiar with the Aurora 12-c sim. Please enlighten me if you have the time.

Thank you.

Take care.




Seems to be an interesting machine.
Too bad it doesn't have keys;-)


Thanks, Bill. It is nice to know someone is using RPN other than HP.

I don't have much use for a financial calculator, but do they have something else on the horizon?

Take care.



The 15C was the "good old days". The 32's were the beginning of the end, and the 48's are downright blasphemous. :)



Really they should have stopped making calcs after the 45 maybe the 65 and still... At work I use a 45 and never lacked anything.



Of course we have mixed feelings about HP!!!

Most, if not all of us on the forum are here because we collect, use, and admire the HP's of the past. (That's why the site is a MUSEUM.)

Then came, "modern times", and values have changed. Many of us think for the worse.

HP dissolved (fired) their calculator division.

So, do we want HP to succeed and make future RPN's? Yes... BUT, will there be a market enough to ever really return to innovation? If not, well, then, NO..... So, I see BOTH SIDES. It's hard to compare the products of today with those of a past era.

I just had to point out why we keep debating this point. Sadly, I doubt we will return to the values of the past, as many here have pointed out.

So, for those who really need the new machines for their work, you have my sympathy, and some bit of hope.

For the rest of us, we have our old "museum pieces."

and for everyone else... they'll never understand what they missed or even what the fuss is about.

I'm going to go comb my wrinkles.



While I congratulate Ben for his discovery, I don't think it is enough to trigger a recall by HP; perhaps just an addendum card.

And, while I'm nostalgic for the old times and models, I didn't saw HP recalling any HP42S for the COMB/PERM bug, etc. The only recall I think they made were for HP35, thirty years ago, for errors in trascendental functions.


I am thinking that HP has only produced one running of the 33s (why else would they not release any to any other stores, or at least give more to walmart?) Perhaps they were looking for bugs in the first 500 they sold, and will make the few minor changes to the ROM before making their next set of them (this month)



I also produced this bug. Good job finding it Ben.



I got the same results. Good find. I found another (minor) one last week when I first got the calc and tried to enter some programs. If you try to enter a fraction in PRGM mode it comes out with commas in the wrong place. Try this: enter program mode and enter the fraction 1234/567. It'll come out looking like this: 12,34/,567. If you enter the same fraction on RPN or ALG mode it works just fine.


Perhaps the reason HP released a set to walmart is to find the bugs. It is more efficient that beta testers, and much faster (the 49g+ was in beta for what, 6 months?). They didn't have 6 months for the 33s. This way, they can simply fix all the bugs before making their next shipment and simply replace the 500 they already sold when someone asks them to.

Has this been done before?



A silver lining, perhaps?

If you own an example of a very early production run of these 33s calculators, and these calculators have a bug which HP will hopefully quickly fix, then you may have a future collector's item in your hands.

(My 2 cents)


I agree, the early 33S machines with these minor bugs are potential future collectables. My sample will take its place next to other calculators in my collection with undocumented "features", including a very early HP-35 version 2 with the ROM bug.

I believe the 33S represents a serious effort by HP to market a calculator not targeted directly at the educational market. Also, the fact that it took three weeks for people to start finding minor bugs indicates that the 33S is a solid product. HP should be commended for their efforts.


According to my copy of the 33s manual, fractions entered in programs should behave the same as is the case with the 32sii---they should automatically convert to decimals.

You may have found another bug.


Ben, you've got a future in the software industry (should you decide that's a direction for you).

That's a pretty obscure behavior, and you went the extra mile and discovered how extensive it was, and formed a plausible explanation that seems to fit the observed facts.

And still in High School, eh?

Good job!

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