|Me and many of my close friends!|
This is a summary of the HHC 2014 that took place in Reno, Nevada from September 20 to September 21, 2014. HHC stands for HP Handheld Conference, which one takes place around the third weekend of September. If you get a chance - GO! The cost of the conference is reasonably low and often you get a special rate at the hotel.
The website for this year's conference is here: http://hhuc.us/2014/
I have been attending HHCs for four years straight, and have been to six overall since 2003.
I drove from Azusa, CA, where I live, to Reno, NV. I honestly did not want to fly and deal with TSA security. Also, I have never been to Bishop, let alone through the Eastern Sierras before. Driving there presented the perfect opportunity to do so. I drove on U.S. Highway 395, starts in Hesperia, CA. The route is in three sections: (1) never ending high desert where small towns pop up on the side of the road every now and then, (2) the eastern valley of the Sierras where each patch of civilization is marked with trees - and in those towns Route 395 became "Main Street" where we had to drive at slow speeds such as 30 MPH, and (3) once I got north of Bishop, a drive through the mountains. Including quiche and coffee at the Black Sheep Coffee Shop in Bishop and several short pit stops, it took me 11 hours to my destination.
|Welcome to Nevada!|
I will give a summary of each of the talks here, accompanied by a YouTube video produced by http://www.hpcalc.org/. The hpcalc.org website is run by Eric Rechlin. I am under a non-disclosure agreement, which means that I will not be able to discuss certain details of the conference due to confidentiality.
DAY 1 - September 20, 2014
A fun tradition is that the attendees sign a box lid. Bill Butler collects the signatures. Also, we also go to dinner and just enjoy each other's company.
On with the presentations!
Namir Shammas - Bisection Plus Algorithms, Remembering Jack Stout
Shammas describes methods of improving and speeding up the bisection method. In general, the "bisection-plus" method involves additional analysis per loop to refine subsequent guesses, while retaining the guarantee the root will be found. The function to be solved is assumed to be continuous.
Jack Stout was a longtime coordinator of CHIP, which was a sponsor of a lot of HP Handheld conferences in years past. Stout passed away on July 30, 2014. More information of Stout can be found here:
Bob Prosperi - Virtual Loops, PILs, LIFs; An Update on HP-IL
What is HP-IL? The HP-IL is a 1980's communication device that allowed Hewlett Packard calculators and printers to "talk" to each other. This is before the USB ports. Some calculators that communicated with the HP-IL include the HP 41 series (41C, 41CV), HP 71B, and HP 75. The HP-IL also services HP mini-desktop models 80, 110, and 150.
A LIF file (pronounced "lif" or "life") is a 1980's version of the zip file.
One can imagine that it is difficult for the 1980's HP calculators and desktops to talk to other devices because of connections. Here Propseri presents a PIL-Box, which was invented in 2009. The PIL-Box is a unit that connects the HP-IL cable and a USB cable that allows users to connect the 1980's calculators directly to a computer with a USB port. Propseri comments that the HP-IL cable is a challenge to find. This something that fans and enthusiasts of the 41C, 71B, and 75 may want to look into.
Richard Nelson - Solving sans Computer, Calculator, or Slide Rule
What do you do when you are not able to use a calculator, computer, or a slide rule to execute mathematical calculations? Nelson, who states that he has an efficiency gene (and I disagree with him, I don't think that's a deficient gene), uses nomograph to solve math problems. Basically, a monograph, also known as nomograms, consists of scales, which include linear and non-linear, that aid in solving math problems. Just pick the scale that represents your input, line up your ruler or draw a line in the required way, and you get your output. There are many kinds of nomographs, and they are still used in the medical field, piloting, and engineering. This is one of my most favorite topics of the conference.
You can see some examples of Nomographs (Nonograms) on this Wikipedia article: http://en.wikipedia.org/wiki/Nomogram
A Google image search will also provide examples.
Geoff Quickfall - Cloud fed: Sprinkle and Strew
Quickfall describes his 1984 thesis paper, and how he used his HP 41C in his project.
Jake Schwartz - Calculator Odds and Ends
Odds: Over the last few conferences, Schwartz and several others including Jackie Woldering, thousands of HP calculator documents, which every attendant received as part of the conference materials. The updated the HPCC Datafile Index for Volumes 1-6 (from 1982 to 1987) which primarily covers articles of HP 41 including programs. I could easily spend days going through all the material provided - special thanks to Schwartz, Woldering, and crew for putting this together!
If you would like to get DVD for yourself, please visit http://www.pahhc.org/ppccdrom.htm to order a DVD.
Ends: The WP 31S, which operates on a re purposed HP 20b and HP 30b calculator. The WP 31S is a scientific calculator It is a two-line alphanumeric display which runs quickly. The WP-31S is has an RPN, non-programmable calculator based on the popular WP-34S calculator (Walter Bonin, Paul Dale, Marcus von Cube). The WP 31S software was developed by Sanjeev Visvanatha and Jonathan Cameron.
Some features of the WP 31S include:
- RPN with a 4-level or 8-level stack
- Fraction Conversion
- 23 memory registers
- An extensive library of physical constants and conversions
To get either a WP 31S or WP 34S complete, you can order one from this website: http://commerce.hpcalc.org/ Supplies may be limited because HP stopped manufacturing the HP 20b and 30b, the bases on which these calculators run.
David Ramsey - Something, Something, Something Dark Side
Ramsey brought his HP 9810 and HP 9820 to the conference. They are huge, desktop calculators, which are definitely collector's items. In this presentation, Ramsey shows the internal components of the HP 9810 and 9820, which include five memory cards, CPU unit, two single card controllers for the printer, and power supply. The five memory cards, each the size of a large handheld, act like a kit which was sent back to Hewlett Packard should any problems occur. Specifically, each of the memory cards each had a different function:
(1) 51 memory registers
(2) Memory Subsystem with an Intel 1103 DRAM
(3) Control "Ass'y" - not many details are known about the "Ass'y"
(4) A board dedicated to an independent "M" register
(5) A board dedicated to an independent "T" register
The main differences between the HP 9810 and HP 9820 are:
- The HP 9810 is an RPN calculator with a 3 level stack. The weirdest thing with the stack is that binary operations (sin, cos, e^x, etc..) returned results to the Y stack, not the X stack. There is no stack lift or drop when operations are completed.
- The HP 9820 runs on an algebraic operating system.
- Both are programmable. The 9820 had a more expansive set of programming commands than the 9810. Also, the 9820 had a nicer program interface.
Namir Shammas - Trisection Algorithms
If the Bisection algorithm isn't enough for finding roots to functions, consider a Trisection algorithm. Simply put, a Trisection algorithm divides the given interval into three parts and decides which sub-interval should be used to generate the next guess. Using test functions, Shammas shows that the Trisection and Trisection Plus methods are faster than Bisection method, and on par with the Newton's Method.
More details of Shammas' Trisection Method can be found here: www.namirshammas.com/NEW/Tri1.pdf
Eric Smith - Scaled Reptiles from (Silicon) Laboratories
Smith makes RPN calculators from scratch, and has wonderful prototypes that he showed the group. One case is made of Mylar and the other is made with a 3-D printer. The calculator operates Free42 or HP-41C emulator software, both the software is made from third parties. You really need to see this video to see the prototypes look like; and if you come to a HHC conference, you get a chance to test one out for yourself.
- Linear Regression for 1, 2, or 3 variables
- Power Fit for 1, 2, or 3 variables
- y^p = a + b*x^q
- z^p = a + b*x^q + c*y^r
- t^p + a + b*x^q + c*y^r + d*z^w
- Polynomial Regressions of Orders 2 and 3