January 2006 Meeting Notes

Dave Jaffe


Starbucks Coffee, Tea, Bagels, and Pastries


LEGO MindStorms and pbForth - CH Ting
"I bought a MindStorms set as a Christmas present for myself. I wanted to evaluate pbForth and see how it works. I constructed a Rovobot and got it to follow a black line. I will talk about pbForth and give some demos."

Ting bought a Legos Mindstorm for $200.

The computer was unable to communicate with the robot due to the overhead fluorescent lights.

Version 2.0 of the software uses a USB interface to an IR transceiver, older version used RS-232 interface

32 Kb of firmware that includes 4 demo programs
processor is a Hitachi H8/300, an 8/16 bit processor
runs on 8 AA batteries
3 motor drive ports and a 2-way IR port
3 sensors - 2 touch sensors and a light sensor for line detection
can the robot be cloned with an ARM chip?
can A/D, D/A, I/O bits be added?
PB Forth, a public domain ANS standard is available
12 K, but some tools missing
BricX CC firmware (Control Center) - Bricx Command Center 3.3
Windows program that communciates with the Mindstorm
supports PB Forth and C programs
Ting's experiences:
he can download PB Forth
can't download multiple lines of source code
can download source code one line at a time

O' Reilly - Unofficial Guide to Lego Mindstorms Robots and Online Resources

VEX is a modular robot sold by Radio Shack
Starter Kit $300
a $20 ultrasonic distance ranging module is available

BAYLUG is the Bay Area Lego User's Group

Lego models and ideas
Lego train on gauge one track

Lego's drag-and-drop visual programming is reminescent of Kim Harris' D-charts in Forth


More New Products - Dave Jaffe
Dave will survey some newly introduced microcontrollers, I/O peripherals, and gadgets that are interesting and can provide useful and unique capabilities to Forth embedded systems.

Presentation in PDF with web links


Lunch - go to TOGO's or bring your own meal and stay at Cogswell


Introductions, Announcements, Rumors, Gossip, and Random Discussions

From Bob Nash:
Lantronix XPORT - embedded device server (ethernet)
Digital filter DSP devices:
Saelig Signal Wizard II for audio frequencies
$400 board - 4-channels
Quickfilter QF4A512 4-channel programmable signal converter - 32 pin part
$200 for 2-channel development kit, $20 for chip
programmable gain
188 Khz bandwidth
anti-alias filter
12 / 16 bit A/D convertor
SPI port
available from Mouser


LabVIEW and the South African Large Telescope (SALT) - Dirk De Mol (National Instruments)
LabVIEW is a dataflow language used in the control and instrumentation world. A short overview will be given of its structure, constructs, functions, and grammar. SALT, a 10 meter-class telescope will be discussed as a case study.

Labview can write Excel files and do FFTs
user designs front panel and Windows
$100 for student version
$2000 for full version
can produce .exe file that does not need a runtime environment
runs on Mac and Linux as well
Labview Embedded - product for chips
SALT - South African Large Telescope - 11 meter
uses Labview for telescope control
scheduling program is written in MPE Forth

Slideshow in PDF - 8.88 Mb


"Watergate" and Forensic Engineering - Jay McKnight
FIG member Jay McKnight was one of the "tape experts" on Judge John J. Sirica's panel that advised him in 1973 about the "missing 18 minutes" in Nixon's tapes. Jay will show and discuss slides from the report, and/or answer your questions. The full report describing the techniques that they developed is online at the AESHC website under the heading "Forensic Audio Engineering".

AP photograph from SF Chronicle - January 19, 1974

Meeting Announcement

| Home | 02/2006 | 12/2005 |