Amazing RPN calculator discovered


I just found this incredible scientific RPN calculator from xxxxx, made in Japan in 1982.

The specification sheet reads like a dream:

Floating Point 1.00000000001E-1024 ... 9.9999999999E1024

12 digits accuracy on most functions, some only 10 digits

Double wide ENTER key

DISP key shows "height" of stack

12 Memories

Statistical functions

And - it is not in db's photo collection ;-))

Your bet?



Omron, I'd guess? I don't think Sharp/Casio/Toshiba ever bothered with RPN, but I know Omron made some RPN models. Anyhow, sounds like a nice acquisition.


You found a Panasonic.
Pinche puta malcreado avericioso. I'll trade you my TI 150 for it.



Quasar HHC-1400 with RPN ROM ;-))




Are you referring to their version of FORTH called SNAP?




I'm not sure - it might be based on Forth...
See the pictures below.



I'm almost certain that this is SNAP, and it's the built-in language on this machine. It has BASIC too, but that was on a plug in ROM.




We shouldn't talk too much about Forth - it reveals our age ;-))

I finished my diploma of Electrical Engineering in 1986 in Stuttgart and worked as a freelancer for companies like Bosch, AGIE and EPSON before joining a "Rapid Protoyping" company in Switzerland in 1990. In the years before 1990 I programmed microcontrollers (I-8085, HD6303) in Assembler and the famous Epson HC-20 in Basic.

My project in Switzerland were the Main-Controller and Display-Controller boards of a desktop blood analyzer, a total of 12 (!) microcontrollers. The smallest ones were National Semi Cops400, the larger ones nice NEC V25's. Every single controller was programmed in Forth, we teamed up with Mr. Flesch from Forth Systems in Germany.

I think early in the 90's it was still a very cool language! Very efficient in performance and compact in the ROM and RAM.

Well, these days the smallest controller we use in our products are ARM9's, TI C6400 DSP's - don't ask about ROM sizes ;-))

By the way, I turned last month 50 ;-))



Ohh, 6303 in Forth :) ¡That brings really nice memories!

I even made a decent multitasking kernel for the 6303-based TDS9090/9092 from the recently disappeared Triangle Digital Services.


We shouldn't talk too much about Forth - it reveals our age ;-))
It is not embarassing. Although some Forth methods are outdated, Forth itself is timeless--not outdated at all--and still offers huge advantages over other more-popular languages today.

The RPN calculator ROM for the HHC is written in SNAP, but it doesn't provide direct access to SNAP programming.

I've done a fair bit of work on reverse-engineering the mainframe ROM, including the SNAP interpreter, though there's still a long way to go. SNAP is a token-threaded variant of FORTH, with some one-byte and some two-byte tokens. From the disassembly I've worked out what many of the tokens are.

I do have the SNAP development module, but unfortunately not the technical documentation.

I've got one other rare HHC module, which is SNAP BASIC. It's a BASIC implemented in SNAP, entirely unrelated to the more common Microsoft BASIC ROM.


BASIC in SNAP, I love it! Ages ago I wrote a forth-like language for the Commodore PET and used it to write a BASIC-like language too, even though it had an early Microsoft BASIC in ROM. I may have to find one of these HHC computers to play with too.......



deal. i'll email you tomorrow. do you FIND this stuff?


How does he FIND this kind of stuff? I wonder how do you KNOW about this kind of stuff... Makes me feel like living in another planet, for God's sake! <*^D


Luiz (Brazil)

Edited: 14 July 2010, 10:44 p.m. after one or more responses were posted


Luiz; It's calculator lust. As a Brazilian - you understand about lust. - db


This one by accident!

A huuuuge box with some nice TI's ;-))



Hi, Joerg, guys;

as I was not aware of this model, I searched the www for it and found that one of these was sold in Brazil for R$400,00 (about US$200) but I could not find any reference about when it was sold. I was also pointed to this link about the Panasonic HHC 1400.

And Joerg: not fair! Without the RPN ROM it is a regular pocket computer!!! Well, it also needs a BASIC ROM, anyway... And as Katie mentioned, the resident OS is SNAP (BTW, what the heck does SNAP stand for? Could not find any concise info...)

NICE! The OS comes in (EP)ROM packets...


Luiz (Brazil)

Edited: 14 July 2010, 11:13 p.m.


The Panasonic and Quasar branded HHCs are identical other than the brand and minor cosmetic differences.


I'd expect a TI-150 to be much more valuable than a Panasonic/Quasar HHC; the HHC routinely sells for a mere pittance on eBay.

On the other hand, the RPN calculator ROM for the HHC is fairly rare. I've got one, but if I didn't, I'd find an extra HHC ROM (maybe an extra copy of Microsoft BASIC), remove the chip, and replace it with a suitably programmed MC68764 EPROM.


And I don't expect a TI-150 for the HHC ;-))

db contributed a lot of nice stuff to my little Datamath Museum and he will receive the whole HHC box with lots of manuals for free...

Just shipped.



Manuals??? Joerg; you're a prince.

Hey Eric; if you know how to copy the rpn rom and anyone wants a copy we could get together sometime and burn a couple (i'm assuming you need two HHCs to do it). i still live only 45 minutes north of where you were living.

does anyone need a new RPN?




Hallo Jörg,

ein Foto ist doch nicht so schwierig, oder? Ich bin genauso neugierig wie Luiz, wie das Rechnerchen aussieht ;)

(I concur supporting Luiz' request)


Here we are - sorry that you had to wait almost a day.

We are rather busy these days (what is good...).



Interesting likeness to:


HA! This IS 'calculator lust'...

Danke, Joerg; Gracias, db!

Luiz (Brazil)


Danke für die Bilder. Mit 5 unbelegten Tasten sieht es so aus, als hätte man den Rechner umgewidmet. Wie sieht er aus, wenn man die Tastaturschablone entfernt?

(Thanks for the pictures. Due to 5 unused keys, it seems the calculator has been "customized". How does it look with the keyboard overlay removed?)


Like any Quasar HHC-1400 ;-))




I have one of those, it came with a carrying case, charger, some ROM chips, and the Printer/Cassette adapter, some paperwork. My nephew gave it to me as a (goofy) wedding present (10 years ago). It apparently had been used by an insurance agent for giving on-site quotes for policies.

I didn't know it was RPN!
But it is Y2K compatible!

It's batteries (NiCd's) are old and don't hold a charge long.

Follow-up: Oops! I just checked again, mine doesn't have the Scientific Calc overlay or the ROM chips needed for that function.
Is it possible I can get a HEX dump of the those ROM chips?

Edited: 29 July 2010, 1:31 p.m.


Ren; Joerg & me checked out the HHC he was talking about and it turns out that although it has the manual and overlay; it did not have the RPN ROM itself. We were bummed. I have found that the Motorola chip was still available as of 3 years ago and it is mountable in one of those plastic frames that the insurance ROMs are sitting in. I think there is a very small market (about 6 or 7) for these: you, me, probably Katie, Michael, Viktor (since this allows three short RPN programs), Telly, & maybe Craig. Who knows - maybe one or two more. I have had no luck so far but if you can find how/where we can get them burned, maybe Eric or somebody can provide the code off their chip and we are all in business. I am waiting for a response on where to get the bare-nekid ROMs. and waiting......


What is the chip?, I do have a small chip burner for 27xxx? family chips,
Hmmm, IIRC the burner needs to plug into an ISA bus slot...

I still might have one of those...


ren; supposedly the eprom is the motorola mc68764. abra electronics had them as late as last january and they can be programmed. the guy who found them had his programmed somehow. i have tried to use abra's website to look it up but their search function can't find it. the search function can't find adapters, boards, resistors, LEDs or anything else either, so i think it is FUBAR, or it just doesn't like linux. i'll try to call soon. -db


I have at least one EPROM programmer that can program MC68764, and I may even have some of them as they where the EPROM equivalent of the ROMs used in the original IBM PC. I also recall making adapters to replace them with the more common 2764, but that would probably not be an option in the confined space of a hand held device.

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