September 2007 Meeting Notes

Compiled by Dave Jaffe

Contributions from Kevin Appert and others


Coffee and a chat


Simple Effective HTML - CH Ting
"Anyone interested in HTML? I can share my very limited experience in building the new Offete website. I am taking the simplest approach to organizing the pages. I only used about 20-30 tags and I think that's all one has to know to start a website. I will show webpages to demonstrate these HTML tags and how to make the best use of them."


Some folks bring their lunch, some folks go to Togos.


Introductions, announcements, rumors, and random access


LaFarr's Steel-Cut Unsieved Primes - LaFarr Stuart
LaFarr is widely regarded as a master practitioner of fast, efficient Assembly Code. He will demonstrate and discuss an incredibly economical method for generating primes and other programming gems.

"Yes, I was encouraged by your enthusiasm and interest, so I decided I should dig out and study (possibly update - The Creeping Feature Creature - you understand I'm sure.) what I had done years ago. I did, and converted it to my favorite assembler (A86 or A386 by Eric Isaacson, details at: ) You wanted a little blurb. How about the following:"

"Back in the days when computers were used for computing, almost everyone wrote a program to generate a list of Prime Numbers. Most generate test numbers, and then do divides (by primes) to see if the test number is prime."

"Simple enough, and easy enough to make several optimizations. With an obvious goal: Generate primes as fast as possible generally with a limited amount of memory. The best that I have found does not use any divides, and only one multiply for each prime it stores in memory."

"I will bring an older Lap-top running DOS 6.2 and demonstrate generating primes as well as a couple other simple little arithmetic programs. I'll probably try to sell the concept that Assembly Language is the only way to really write fast code. It might be interesting to discuss and share a few programming tricks."

"In case you are interested in how programming was done in the good old days has a story about Mel - A REAL Programmer."

LaFarr Stuart's website
Bio webpage
Assembly Programming, Intel 8086 By Example
Writing HTML is quite Easy, but there are some rules.
My Forth and Mathematical Stuff
Borland Turbo Assembler
Terse Algebraic Assembly Language
This is a list of things I talked about at the SVFIG meeting on 22nd Sept.

Graphical proof of Pythagorean Theorem
Graphical proof Area of a circle is Pi(r^2)
Tools needed for Assembly Language programming.
        An Assembler (I like A86 by Eric Isaacson)
        A description of the processor instructions
        A description of the operating system functions
        Several tools such as:
                A good editor (I customized SemWare's Junior Editor under DOS
                        - worth it just for the spelling checker)
                A Debug facility (DEBUG comes with Microsoft Windows ??)
                A File Dump routine (Include my DUMP.COM)
                A File Compare program (SUPERC - contact me about it)
                A program to read the computer clock (for timing)

Programs I demonstrated:
DT        Prints Date & Time optional text after DT on command line
PAN       Phone Alpha to telephone number
SX & SXS  Sequence Extender (SXS shows steps--more for debugging.)
NP3       New Prime number generator - uses 386 32-bit registers.
            Outputs 1 byte for each prime
                Use KCHAR and DUMP to show.
                Don't test multiples of 2 or 3
                P & Q Tables
                DS and ES are separate 64K Segments. SS is 1000 bytes higher
                For speed Q is in ES & P in DS at same address
                The first 4000 hex bytes of ES is the output buffer
                Put value being tested at top of Q
                Don't need low order bit
                At any point in time the high bits are all the same

PPN   Print Prime Numbers to display in decimal, variable number of columns
PGC   Print the Count of Gaps between consecutive primes
PPT   Print Prime Twins (only the last of the two)
KCHAR Keeps first n characters of a file
DUMP  Displays a file in Hex and ASCII

 Directory of my prime programs as of:
        2007-09-20 Ordered by Size

HELLO    COM            21 01-10-29   15.49
PAN      COM            82 04-05-19   19.01
KCHAR    COM           342 93-11-19   11.24
DT       COM           394 98-11-01   15.53
PGC      COM           402 07-09-20   11.51
PPN      COM           572 07-08-23   20.40
PPT      COM           576 07-08-29   16.59
DUMP     COM           576 01-12-02    9.23
SXS      COM           702 02-08-21   18.17
SX       COM           704 02-08-21   18.14
NP3      COM           884 07-09-04    6.32
       11 file(s)          5 255 bytes

Quick notes added to help with programs:
To get "tiny help", TYPE any of the .com files except: HELLO.COM & PAN.COM

The .8 and .S8 files are source, however I use ` names to drop in
"boiler-plate" to help understand it a little better I have included PGC.8
which has everything expanded. 

A86 allows local labels, which can be re-used. They are a single letter
followed by a number. A forward reference is preceded with a > without it it
is a backward reference.
Files - 16 Kb zip file




Audible Computing, Part 2 - Masa Kasahara
What would happen if we only relied on our hearing when using a computer? Masa will continue his experiment based on the feedbacks he received in the previous talk. He will discuss Prototype 1 in detail and also touch upon his view of human and computer languages inspired by Ting's papers on computers and Zen.

Slides - 1.3 Mb pdf file



Other items:

Meeting Announcement

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