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HP Forum Archive 14

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"speed" of 11c
Message #1 Posted by Bram on 24 Aug 2004, 4:58 a.m.

A nice way of getting acquainted with a (new) device is to convert an existing program and get it running. I did so with a program for my HP-29C and ran it on an 11C. It went well, but I was amazed, if not baffled, to notice that the 11C ran at less than half the speed of the 29C. It was the last thing to expect from a 2-generations-younger calculator.

My queens program finds the first solution in about half an hour on a 29C. On both the 20S and 32SII it takes 5 minutes (newer devices), but with an 11C youíll have to wait for more than one hour. I guess this is the *only* drawback of the latter, but a very important one.

(Off topic: On my Psion Series 3mx it takes a mere 2 seconds, although the programming language OPL doesnít even really compile, but this one is a real computer)

      
Re: "speed" of 11c
Message #2 Posted by Valentin Albillo on 24 Aug 2004, 6:40 a.m.,
in response to message #1 by Bram

Bram posted:

"I was amazed, if not baffled, to notice that the 11C ran at less than half the speed of the 29C. It was the last thing to expect from a 2-generations-younger calculator."

Just have a look at their respective power consumptions. One of the main design goals of the Voyager series was to minimize power requirements so that the batteries would last for long and thus a charger/adapter wouldn't be needed at all. They succeeded in spades, with my own HP-11C lasting for 10+ years between battery changes (and 15+ years aren't unheard of). It's amazing that the CPU can still run at such a reasonable speed given the extremely minimal current it draws from its power source.

On the other hand, the HP-29C draws orders of magnitude more power from its batteries and so they'll last just a few hours, at most. Even if you could switch off the display completely (instead of leaving a single "."), they wouldn't last much longer.

I hope this explains the speed difference, and I hope you'll appreciate that even using 1/100th the power, say, it still manages to run at 1/2 the speed.

Best regards from V.

Edited: 24 Aug 2004, 6:44 a.m.

            
Re: "speed" of 11c
Message #3 Posted by Ronald on 24 Aug 2004, 7:41 a.m.,
in response to message #2 by Valentin Albillo

If you want to increase speed, you could replace the timing capacitor in the HP11C with a smaller value, 70% is certainly possible. Althouhh power consumption will increase about linearely, it still gives a very long lifetime of the batteries. I replace the batteries anyhow after a certain period, do not want to risk leakage one day unnoticed.

Ronald

            
Re: "speed" of 11c
Message #4 Posted by Bram on 24 Aug 2004, 10:48 a.m.,
in response to message #2 by Valentin Albillo

Clear answer, Valentin. Thank you.

Would I have been the designer, I strategically wouldn't have made it slower than its predecessors. Still I could have stressed that 5 years battery life is very long. Canít imagine what the sales would have been this way. Prefer not to think about it. ;-)

Iíll leave the device as it is. I have ďtastedĒ the 32SII with alpha display, and I think I will program that one instead. So on the 11C speed isnít really an option. Having it always available and operational however, is.

Edited: 24 Aug 2004, 10:55 a.m.

                  
Re: "speed" of 11c
Message #5 Posted by marais on 24 Aug 2004, 3:24 p.m.,
in response to message #4 by Bram

In fact, according to the 11c user's guide, they only claimed 1 year of battery life. Amazing from today's perspective with all its marketing hype.

      
Re: "speed" of 11c
Message #6 Posted by Katie on 25 Aug 2004, 9:05 a.m.,
in response to message #1 by Bram

What I find even more amazing is that 20+ years later the 12c is still just as slow. It's still bought and used by countless thousands of financial professions who still sit there patiently waiting for the bond price calculations to complete! In my job as a consultant I've been telling these "countless thousands" about the 17Bii for years and they just don't want to change. Speed seems unimportant to them and they never have to think of changing the batteries. The old HP was right (the new HP is virtually never right about anything) to not have worried about slowing down the calculator in order to extend battery life.


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