All this article deals with the way some of us have made the continued use of the HP41 possible, even some 30 years after this fabulous machine was first introduced by HEWLETT-PACKARD.
I am aware that many more people than the two ones celebrated here have been – extremely successfully – involved into the current revival of the HP41. My hat down to them also. Still I wish to draw your kind attention towards two very special men I have met in this field.
This might be a long story - maybe a repeat to some of you - but I feel higly indebted towards two very special people : Jean-Francois Garnier and HrastProgrammer. I wish to publicly command their extraordinary expertise and most importantly their outstanding help, as well as faithful and friendly support in the past 30 months.
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It all started some 25 years ago when I was an aircraft carrier pilot flying the CORSAIR II single seat Attack Aircraft in the US Navy under an exchange program with the French Navy.
From previous course at the French Naval Academy, right after flying which has always been my favorite professionnal occupation - and I now fly the good old DC10-30 worldwide as a CARGO aircraft - I have always been extremely fascinated by Celestial Navigation, by other items or people too … but this is an other subject. :-) )
As soon as the HP41 was introduced, I realised that I was holding in my hands THE Calculator which could eventually allow me to fulfill a long time dream : automatic computation of Sun, Moon, Planets and brightest stars position WITH AN ACCURACY BETTER THAN 6 ARCSECONDS - the accuracy achieved through the use of the Nautical Almanach - AND (VIRTUALLY) NO TIME SPAN LIMITATION, all this in a “handheld” machine.
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Starting in 1979 I began writing a number of Celestial Navigation routines, taking some inspiration of the then extraordinary HP41 NAVIGATION Module ( Congratulations again M. Kenneth Newcomer !!! ). To fulfill the objective of “unlimited” time span accuracy, thanks to information obtained in Washington from late Dr Leroy Dogget of the U.S.N.O. , I then met in Paris several times with Dr Jean Chapront and late Dr Pierre Bretagnon from the Bureau des Longitudes who were at that time just finishing their new ELP2000 and VSOP82 theories which they kept further developping and improving over the subsequent years.
For the Moon I am now using ELP2000-85 and for the Planets - all 8 Main Planets are included in my Software - I am using VSOP82+NGT which is extremely similar to VSOP87. VSOP82+NGT enables computations with 6 variables while VSOP 87 only yields the three usual X Y Z Variables. Computing with 6 (elliptic) variables immediately gives access to the planetary speeds while VSOP87 would need to be somewhat differentiated for this aim. For the stars I am using the FK5 Catalog, an area where the more recent FK6 Catalog would give little if none leading edge even on a long time span when it comes to the Celestial Navigation required accuracy. With the FK5 Catalog I achieve a computation accuracy better than 2/1,000 arcseconds on stars apparent coordinates when comparing my results with the examples then published in the Astronomical Almanach form 1984 onwards.
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To solve the problem of the required Memory Capacity, I then identified W&W Gmbh in Germany and visited Wilfried Koetz and his micro-code software Engineer Heinz-Ado Arnolds. I first purchased one 32K RAMBOX from them. Since it was to “small” because I needed 64K, I then purchased one RAMBOX II and finally purchased their HP41CY Turbo. This superb machine allowed me to fully develop and test my Software and demonstrate that I exceeded my requirements in all respects. Happy me !!!
Unfortunately HP41 has become old and started decaying over the years. I was really worried that all my important work could not be saved in any way and would somewhat disappear.
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This is when both Jean-François Garnier and HrastProgrammer came to play.
Jean-François had earlier developped his EMU41 running on PC. He first saved all my software ( some 64 K with over 30500 program lines ) from my HP41CY Turbo into his Computer. He then offered to me - for free - to upgrade his EMU41 into an HP41Y Turbo emulator. Very shortly after his kind offer Jean-François achieved this objective as a superb Piece of Art.
Thanks to you Jean-François, I have been able to save all my work and my software now runs some 600 times faster on EMU 41 than on a standard HP41 !
As an example, the (long ) INITialisation Program I need to save time for further computations takes some 85 minutes to run in a standard HP 41 and … less than 9 seconds on my laptop running EMU41 . CONGRATULATIONS AGAIN JEAN-FRANCOIS !!!
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As I earlier mentionned, running Celestial Navigation Software on a HANDHELD computer has been my ultimate objective. At that time Jean-François Garnier introduced me to HrastProgrammer, and to make it short, Hrast did an extraordinary development work for me on HP48GX at an extremely reasonable price given the huge development task he subsequently did for me.
Off the record and like Valentin Albillo (Hi Valentin !), I find HP48GX programming extremely cumbersome when compared to HP41 programming. After 2 1/2 years of regular use of HP48GX, I just start feeling comfortable with a basic use of this machine. It certainly has something to do with my “old” age ( I am 53 now ) and maybe with the ( poor ) quality of the HEWLETT PACKARD documentation for the HP48GX while most of the earlier HEWLETT PACKARD Documentation for the HP41 has always been highly regarded and commended as a MODEL in this area.
Starting from his current HP41X/Z Emulator running on HP48(GX), Hrast was able to upgrade it into a most superb HP41X/Y/Z Emulator with the most outstanding features being as follows :
- All my 64K Navigation Software running on the 2 x 32 K Q-ROM Blocks of a RAMBOX II is saved as an “HP41Y” Object on the HP48GX,
- Programs and Data can now be saved to HP48GX and recalled from HP48GX through totally different manners :
o Virtual HP41 cards,
o Separate HP41 Pages ( any of the 16 pages corresponding to Pages 8 to 16 of either BlockA or BlockB of the RAMBOX II ),
o Full 2 x 32 K Q-ROM blocks ( the HP41Y Object on the HP48GX earlier mentionned ),
· Transformation of the latter into 16 4K files to be inserted into Jean-François’s EMU41,
· HPIL,
o and very importantly for me, direct saving of programs listings from HP48GX onto PC/Laptop under .txt format files. ( By the way, through a USB-COM converter, I am now able to connect both ways my HP48 and my Laptop which has 2 USB ports and no COM Ports). Given the equipment I had at hand, saving Programs listings under .txt format files earlier required that such programs be located into an HP41 - meaning that any modified or newly developped program on HP41X/Y/Z had to be manually re-typed on an HP41 Machine - then resent to HP48GX + INPRINT Program through HP41 IR Module, then sent from HP48GX to PC through KERMIT
- I am now using the extensive and incredible Data Exchange Software Hrast developped for FAST DATA TRANSFER between HP48GX-PC, or HP48GX-HP48GX or HP48GX-HP49G !!! This is quite an achievement here compared to some much bulkier software earlier developped by HEWLETT PACKARD for example. Hrast’s software is running at the incredible speed 1 Kbyte/second. As a “cherry on the cake”, I can even now save entire HP48GX 128K Pages, and exchange them onto either PC or another HP48GX !!! Whaooo !!!
- And of course for my HP41X/Y/Z customized version, I do enjoy all standard features of HP41X/Z ( over 3000 RAM registers, over 30 HP41 modules , 3 times the standard HP41 computing speed to name only a few features of this Magic emulator )
Hrast, again I am extremely pleased to CONGRATULATE you in public !!! Your outstanding kindness, friendly and undefective quick reactions as well as everlasting support must be again commended. For me you Hrast are certainly (one of ) the World most extraordinary HP48/HP41 Expert, Wizard and Magician !!!
With my VERY BEST REGARDS to Both of you Jean-François and Hrast
Antoine M. Couëtte