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HP Forum Archive 16

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Hooray to Valentin Albillo!
Message #1 Posted by Antonio Maschio (Italy) on 30 June 2006, 10:25 a.m.

Dear Valentin,

I just input your "Tried & Tricky Trigonometry" program on my Kynpo HP-12C, and I'm astonished for the precision it reaches (only the last out of nine decimals is different by two unities at maximum!). I use my HP-12C for daily work, but I had to add a scientific unit for trigonometry (I'm a civil engineer). Now I can do anything with my HP-12C.

The only problem is that it is quite... slow. Any advice? But anyway, since I do rare calculations based on trigonometry, I guess I can live with it.

Thanks, again!

-- Antonio

      
Re: Hooray to Valentin Albillo!
Message #2 Posted by Les Wright on 30 June 2006, 12:56 p.m.,
in response to message #1 by Antonio Maschio (Italy)

Sorry if I missed the relevant thread but I would be very interested in this routine. It would be nice to do decent precision trigonometric calculations occasionally on the 12c or 12cp.

Les

            
Re: Hooray to Valentin Albillo!
Message #3 Posted by Jeff O. on 30 June 2006, 1:25 p.m.,
in response to message #2 by Les Wright

Valentin's HP-12C: Tried & Tricky Trigonometrics available here.
Gerson W. Barbosa also developed a trig program that works only on the 12CP, available here.
I put Valentinís in my 12CP, they work as advertised and are reasonably fast.

            
Re: Hooray to Valentin Albillo!
Message #4 Posted by Valentin Albillo on 30 June 2006, 5:24 p.m.,
in response to message #2 by Les Wright

Hi, Les:

    The link kindly provided by Jeff O. formerly in this thread does point to the outermost level of my web site, but for the precise article which includes and discusses the routines you're asking for, this is the direct link which will immediately download the full PDF article:

    HP-12C Tried & Tricky Trigonometrics

    Thanks for your interest, I hope you'll find it both enjoyable and useful, and

Best regards from V.
      
Re: Hooray to Valentin Albillo!
Message #5 Posted by Valentin Albillo on 30 June 2006, 5:20 p.m.,
in response to message #1 by Antonio Maschio (Italy)

Hi, Antonio:

"I just input your "Tried & Tricky Trigonometry" program on my Kynpo HP-12C, and I'm astonished for the precision it reaches [...] The only problem is that it is quite... slow. Any advice?"

    Thanks for your very kind words, much appreciated.

    As for its 'slowness', I'm sorry but it's the best I could do at the time under the original HP-12C's program size and hardware limitations, plus the mandatory, self-imposed requirements of comprehensiveness (all 6 functions at once), accuracy, and input range I set out to fulfill.

    As far as I know, no other published programs achieve a better performance while meeting all those hardware and specs requirements, and the easiest way to improve the functionality is simply to use an HP-12C Platinum, which is faster and further it allows for much larger programs, which can then be made to implement faster algorithms.

    Thanks again, very glad you enjoyed my article and found the routines useful, and

Best regards from V.

            
Re: Hooray to Valentin Albillo!
Message #6 Posted by Antonio Maschio (Italy) on 1 July 2006, 4:37 a.m.,
in response to message #5 by Valentin Albillo

V.A. wrote

Quote:
...the easiest way to improve the functionality is simply to use an HP-12C Platinum, which is faster and further it allows for much larger programs, which can then be made to implement faster algorithms.

I know, 12C is not that fast. Your effort is surprising. I guess nothing can be done to reach more performance.

Ciao.

-- Antonio

                  
Accelerating an older HP-12C
Message #7 Posted by Karl Schneider on 1 July 2006, 5:49 a.m.,
in response to message #6 by Antonio Maschio (Italy)

1980's-design Voyager-series calculators can be accelerated by connecting a small inductor in parallel with its existing LC resonator circuit, in order to speed up the clock. Check out this link:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv015.cgi?read=78272#78272

If your HP-12C model is suitable, it can run up to 2.5 times as fast, with a 33 uH inductor. Still well short of Saturn-processor speed, but a very pleasing improvement.

Sorry, I didn't take any pictures...

-- KS

                        
Re: Accelerating (an older?) HP-12C
Message #8 Posted by Antonio Maschio (Italy) on 3 July 2006, 2:33 a.m.,
in response to message #7 by Karl Schneider

I've got a Kinpo model, with 1xCR2032 in place of 3xLR44 batteries (CN130xxxxx).

Does this model use a Saturn?

Can it be accelerated as you propose?

-- Antonio

Edited: 3 July 2006, 2:34 a.m.

                              
Re: Accelerating (an older?) HP-12C
Message #9 Posted by Karl Schneider on 3 July 2006, 3:41 a.m.,
in response to message #8 by Antonio Maschio (Italy)

Antonio --

I don't believe that Kinpo had any role in a 2001 Chinese-made HP-12C, which used what I believe is the same class of processor as did all other Voyager-series models (except the 12C Platinum).

An excerpt from Eric Smith's comments in the article linked in my earlier post:

In later HP-12C prodution, the CPU and RAM/ROM/Display chip were integrated into a single chip, the 1LQ9. I do not know whether any other Voyager models were ever made using the 1LQ9. It is probably possible to speed up a Voyager using the 1LQ9 by the same technique, but neither Ken nor I have tried it.

Even more recently, the design of the HP-12C changed to use a single coin cell rather than the traditional three button cells. Since the operating voltage is reduced, they may have had to redesign the electronics yet again. I have not opened one of these models.

The newer HP 12C Platinum uses a Sunplus SPLB20D microcontroller containing a 65C02 equivalent CPU core.

Edited: 3 July 2006, 3:43 a.m.

                                    
Re: Accelerating (an older?) HP-12C
Message #10 Posted by Antonio Maschio (Italy) on 3 July 2006, 4:50 a.m.,
in response to message #9 by Karl Schneider

So you assume my HP-12C may be accelerated, having an internal equipment in chips which is the same of the old American models, don't you?

Has anyone ever tried?

-- Antonio


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