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A blog for electronics professionals, amateurs, hackers, and anyone interested in the world of electronics.

24 July 2011

Advanced Calculations

(Or how 1989 - 2011 = 15+30+34+41 )

Thanks to Make Magazine Blog for mentioning my article on calculators (see Difficult Calculations ). It seems that I am not alone in my calculator geekery. Page views shot up by a factor of 100x in a couple of hours!

Inevitably though, no sooner had I written the article than things started to move on. It looks like Hewlett Packard aren't totally devoid of sense after all. Thanks to Dave Jones of the EEVBlog for pointing me in the direction of this:

Yes, this is from the real Hewlett Packard web site. This is a screenshot of the Google cache (see here) of HP's Singapore web site. (Screenshotted just in case the cache gets overwritten) Similar pages were on other nations HP sites too, including the Indian version. I checked, and it all looks legitimate and not a spoof. At the time of writing, HP still hosts a photograph of the calculator in question, an HP-15C:

HP-15C Limited Edition

Investigations by the forum members at the HP Museum site have revealed that the "HP-15C Limited Edition" will shortly be on sale in Japan. No information is available as to whether they will be shipping them in other countries.If they do appear in the UK, then one is going straight on my shopping list.

It looks like a pretty close copy of the original, but the brushed aluminium bezel around the display has been replaced with what looks like white plastic, and the printing somehow looks less crisp. My guess is that Kinpo have been brought in once again by HP, and rather than simply producing a copy of the original, they have re-engineered it to maximise cost savings. Something which has rather back-fired on them in the past. As it stands, the (still in production) HP-12C internals have been converted to an ARM processor based system for some time, so a new version of the 15C and 16C should be straight forward.

Back in the 80s, the HP-15C cost $135. It looks like the new version will sell for an RRP of $129. That is fine in the US, the land of discounts and coupons, but I suspect it will come out at £129 here in the UK after taxes. Given that the HP-15C is based the same hardware used by the HP-12C ($70) then it starts to look a bit expensive. It is a shame that they didn't go the extra mile and produce the HP-16C too, which adds binary and hexadecimal functionality.

The WP-34S

It looks like the HP-12C re-purposing project (that's the polite term for hacking now) has stalled (see here) but the project to investigate the potential of the HP-20B and HP-30B business calculators seems to have moved onwards very quickly indeed (see here), enabling vastly more functionality, based around the HP-42S core software, but very much expanded upon. In fact, it does so much more, that the developers have had to print a whole new set of key legends:

Original HP-30b
Modified with WP-34SFirmware and key legends

Yes, these are the same calculator. I do wonder just how robust the stickers are, but reports seem generally favourable. A complete reprogrammed calculator + overlays is on sale at £76:98 / €84:68.  The firmware manual / user guide is available here.

Do you know what I love about it though? It has markings on the keys - and this is the important bit - I don't know what they all mean. Seriously, I have a row of letters after my name, I have been doing engineering maths for decades, but yet there is stuff in there that is a mystery to me. Sure, it is statistical stuff that I will never need, but that doesn't matter, it means someone is finally adding new functionality to calculators. It makes me feel a bit like when I was a kid with my nose pressed against the window of the glass cabinet with all those mystical electronic boxes inside.

So that is 15, 30, and 34 dealt with (see the blog title), how about 41?

Well, processor designer Monte J. Dalrymple has reverse engineered the HP-41C, and then created an improved version of it on an FPGA. I mean - seriously - it doesn't get much more hardcore than that does it?

Lots more information here on Monte's site

The thing is, all the essential hardware is on an FPGA. It is a relatively (and I use the term recklessly) easy job to hook up your own LCD and keypad, and you have your own HP-41C clone. All it needs is a millionaire willing to stump up enough money to make moulds for the enclosure. Some things have simply got to be done.

Suddenly, the world of calculators just got more interesting.