last update: 7/17/05 (m/d/y)


That is a beloved part of the history of the U.S. of A.: Lewis and Clark had been sent 1804 on a trail to find a way through the Rocky Mountains to the Pacific Ocean. Several names of participants of this expedition had been used by Hewlett-Packard as code names for the Pioneer calculator series.

There are only a few pioneers around who went on the way to another virgin land, the emulation of those calculators. Sébastien Carlier was one of them (yes, JF Garnier too -- and for sure I forgot to mention some others), who brought the HP-48S/SX and -48G/GX as Emu48 to the Windoze-PC. Christoph Gießelink debugged and improved it (nay! - not Windoze - "only" Emu48) as close as possible to the real hard ware. Based on this work Christoph prolonged the life span of all HP Pioneer calculators by their emulation. Presumably even HP uses (used?) his emulators to test new calculators before production.

So it's worth to have a closer look at the homepage of Christoph Gießelink.


And now (summer 2004) HP offers different CDs with several emulators, alas for teachers only and educational purpose. Be happy, if that's not your business you may still use most emulators mentioned here for free. Well, you may donate what you find appropriate.

Be warned, those emulators do not work by 'click-n-run', you have to read carefully the given information. It will take you about one weekend to get over the hurdle transferring an image (not a photo) of the ROM from a calculator you own to the PC; otherwise the emulator has no firmware to interpret. I do not offer any ROM images without authorisation in written by the copyright owner. There are rumours - and I hope they turn true - that HP may offer ROM images of some (or all?) calculators. I may only give some hints, links, and a few 'skins' that I made. New additions will currently not follow (this is not a skin-factory), only when I've worked out legible recipes on how to migrate some calculator ROMs to the PC I will publish them here. (Even if you do not plan to do your own skin I recommend the KML description, just to get an idea of what may be possible.)

To be clear: i) the information given on this site you may find elsewhere too, ii) none of the emulators mentioned here are programmed by me, iii) only some 'skins' (modified photos and "KMLs") are my hats off! for those excellent emulators.


Emu10 emulates the HP-10B, HP-20S, and HP-21S. Not published yet and will probably not be published in the near future. The chance is quite high that it will never be published. For a normal user there is no way to migrate a ROM image from the calculator to the PC and Christoph will not hold a candle to the devil.

There is a HP-10BII version from Sébastien Carlier. It seems to contain the calculator's ROM concealed in the EXE and so it runs without further ado. Alas it does not save its status and on every start of the emulator you get a HP-10BII set to the factory defaults. For Sébastien's quite dark faceplate a brighter replacement here (95kB).


Emu28 emulates the HP-18C and HP-28C.
see here on Christoph's Emu28-dedicated page
this is the recommended approach to migrate the ROM, for a time and battery consuming experiment first read this hint, then that cookbook recipe.
two from Christoph are in the a. m. Emu28 page, currently none from me
Do not give up too early if you fail for some reasons transferring the ROM. If you do need an emulation of your HP-28C it is worth the effort.


Emu32 emulates the HP-14B and HP-32SII. Alas not published yet and will probably not be published in the near future. The chance is quite high that it will never be published. The reason is the same as for Emu10.


Emu42 emulates the HP-17B, HP-17BII, HP-19BII, HP-27S, HP-28S, and HP-42S.
The former version 0.10beta1 from Christoph did neither support HP-19BII nor HP-28S and perished due to the effort of Erik Ehrling (Sweden). Now you find the full version at With its "key-hit recorder" (Menu Tools/Macro) all the a. m. calculator models are "programmable" in this emulation now. To push in external data I use a Macro Editor.
JF Garnier describes how to migrate the ROM of an HP-42S. For the other calculator ROMs I'll add a recipe ASAP. (The HP-19BII is an issue in this respect, without help from HP there is no way to get its ROM.) To check the integrity of your transferred ROM image use the checksum checker.
Just an incidental remark: which of the calculators of the Pioneer series is emulated by which emulator is somehow linear. More dimensions emerge as for every type there may exist several ROM versions, there are several skins (KML files) each with it's advantages in appearance or value in use, and you may set up for every calculator several state files each for a dedicated task. Just focus on your needs except you are infected by the collector virus. Another warning before you download my skins: when I made them for my own use I had not in mind anybody else. So it is quite possible you do not like them. Hard cheese!

There are enough nice skins at Those from me here are not so serious as I modified the photos in a manner to remind it is an emulation (what may not be adequate in quality to the underlying program). Just have a look:

  • Here one skin for the HP-17B (66kB) with a Trading is War-look and two others for the HP-17BII (161kB), one of them is a Gold-Vreneli for the Swiss banker <G>. All three use the same keyboard mapping (what is rather meant for the HP-17BII in RPN mode). Scans are taken from the internet but are strongly modified now. The 'faceplate' for the HP-17BII is a picture of the HP-17BII+ (what may be a misleading fake, but it looks so good). The Gold-Vreneli shows how you may revarnish your favourite calculator according your gustatory - or corporate identity.
  • This skin for the HP-27S (104kB) I call blue baby - as it is a non-UPN model.
  • As Emu42 has no restrictions any more I may now publish a strange HP-28S skin (152kB). Strange in that the photo for it was not orthogonal and I zoomed it out to prevent a screen filling faceplate. Now the emulated display is too big and does not fit in the LCD mount. It lacks the photo-realistic look but with it's smaller faceplate its efficient for all days use.
  • An «in memoriam HP-41»-skin here (122kB). It's mapping of the calculator keys to those of the PC should give easy access to the most often used functions (S=STO, R=RCL, Tab toggles Alpha mode, and so on). I regard it as work in progress and offer it in the hope it could serve you as starting point to make a man-machine-interface of your own touch. In addition a quite "nasty" skin here (11k) to make a distinct difference to the nice one above. I use it for quick-n-dirty tests when it does not matter if it ends with a screwed up state file (what never happened up to now anyway).
Note 1:
There are a few specialists who added more RAM to the real HP-42S. To emulate that you just need to enter the line "Class 32" (without quotes) in the Global section of the KML file and start a new calculator (menu File/New). If you like to keep all data of your emulated calculator and need more storage use the state-file-builder.
Note 2:
If you do not own an HP-42S where you may migrate the ROM to run Emu42 with it — use Free42. It is a simulation very close to the real HP-42S but several times faster, and furthermore it feigns a printer too.
Some «chow» for the HP-42S:


Emu48 emulates the HP-38G, HP-39G, HP-40G, HP-48G, HP48G+, HP48GX, HP-48S, HP48SX and HP-49G.
The ROMs of these machines are available since long time, see here. As such Emu48 is well known and widely discussed in the internet, but I mention it here once more, just to be complete.
see here on Christoph's Emu48-dedicated page
see here and there, or get the last CAS for HP-49G.
What you get from the net is well done, just see here and there, so from me only
  • a grape-green HP-39G+ (179k), alas just a little bit too big for a resolution of 1024x768, therefore in addition a circumcised, peach flesh coloured HP-39G+ (131k) - these two are a fake similar to the a. m. HP-17BII+ because the photo is from the HP-39G+ but "only" an HP-40G is emulated,
  • an ugly HP-40G (143k), and the same with reduced colours (75k), both squeezed to fit on a 1024x768 screen, and
  • a skin for an HP-49G (115k) that fits nicely between the XP-Task-Bar and Office97-Shortcut-Bar on a 1024x768 screen (all I found was a bit too big). I use it with the last CAS release (version 4, 10/05/2003).
to make life easier I suggest getting a ready to run package like that from Colin Croft.

Notes for the User

When you run and close one of the a. m. emulators the first time you are asked to store a file. This state file contains especially the RAM data of the emulated calculator and which KML to use with it. Choose an appropriate name (I advice the codename of the real calculator, or a clue related to the skin, or what you planned to do with this Emu) and accept the suggested file type (suffix .E42 for example). In your filelist (Windoze Explorer or similar) mark this new file, then do an Open with... and navigate to the appropriate program (Emu42.exe in this case). Next you may put a link to this state file on your Desktop or Shortcut-bar.

Repeat that for all calculators you like to emulate and for all skins you want to have easy access. Now you may start very simple your preferred HP Pioneer Calculator or several different ones simultaneously to impress your colleagues.

If you run Emu28 for HP-28C and Emu42 for HP-28S on the same PC choose for the "RAM"-file of the later the suffix (file type) .E42. Using the suffix .E28 for both is ambiguous.

Where to look for more

That should be enough for several sleepless nites <G>.

One more Word

This page is a result from the Allschwil User/Collector/Emulator Programmer Meeting of 2003. Although many different topics had been presented I show here only the field of my interest. (I hope not to upset anybody with my limited focus. Otherwise take that memorial coin as compensation.)
Here the URLs of participants I found:,,,,

Allschwil Meeting 2004

ASAP I'll add more URLs.
Tramway No. 6 in Basle City, a course from the German border in the north, passing at Fondation Beyeler in Riehen, through »tout Bâle« to Allschwil next to the French border. (The photo is modified to fade away the driver.)

Read the legal stuff for this page.