Saturday, August 22nd

Stanford University
Terman Engineering Center
Room 556

Terman Engineering Center can be found on these maps - just search for Terman: Google map or Searchable Stanford Campus Map

There is open parking on weekends. Park in any A or C or metered space.

Take the elevator to the 5th floor. Walk across the foyer and up the ramp just to the left of the glassed-in office. Room 556 is at the top of the ramp - entrance on the left.

Wireless Internet access is anticipated (though not guaranteed) at Stanford, so bring your wi-fi enabled laptop.

If you would like to have meeting announcements e-mailed to you, send the message Subscribe SVFIG Meeting Agenda to: George Perry

Meeting Agenda for August 2009

10:00 --- Coffee and a Chat

10:14 --- Videos from July 2008 Continued
That month our room at Cogswell wasn't available, so a few members convened at Ting's meeting house in San Mateo. Masa videotaped most of the meeting. Was Bill Ragsdale there? Dave Jaffe was there, so we'll have a look at:

Interesting Items - Volume 11 - Dave Jaffe
Dave continued his survey of interesting newly-introduced microcontrollers, I/O peripherals, sensors, products, and gadgets that can provide useful and unique capabilities to Forth embedded systems.

11:40 --- Lunch
Lunch on-campus is most likely, but open to discussion. To avoid the "noon lemming effect", we'll leave a little early.

13:00 --- Introductions, Announcements, Rumors, and Random Access

13:23 --- Computing Logarithms and Exponentials - Eric Smith
The most common algorithms to compute approximations of transcendental functions (including exponentials and logarithms) use polynomial approximations. Such algorithms are well-suited to microprocessors with high-performance floating-point hardware, but are extremely slow otherwise. Since many embedded systems use processors without floating-point hardware, algorithms that do not require multiplication are useful.


14:28 --- Five Topics for Discussion - Jim Harrison

  1. Why floating point isn't "friendly" - it isn't associative - and how to make it so. My opinion: it isn't worth the trouble.

  2. While I'm waiting for GreenArrays (GA), hello XMOS. I will bring an XMOS board and chips to show and tell. I already have the development board and hopefully the chips will arrive by Friday.

  3. Community building in Forth? This is an invitation for people to collaborate on porting Colorforth to XMOS, including documenting the whole process. This will serve as a general tutorial for porting Forth. Why collaborate? I haven't started and I have never done anything like this before. Why XMOS? It has a simple instruction set, is not very expensive, and the chips are available.

  4. Quaternions in Forth. I will use quaternion multiplication to illustrate "good" (and bad?) Forth programming. The discussion will start with browsing a thread that I started on the Colorforth list and continue with comparing Colorforth's virtual machine versus other Forth's VMs and how that impacts the coding style.

  5. Opening session of the Haypress Creek Fan Club. I'm sure other SVFIG members have been reading Chuck's blog. I have questions, perhaps others do as well, so perhaps we can discuss them together.

16:00 --- Adjourn - maybe earlier if we run out of gas (or electricity)

How you can help SVFIG:

  • Bring your speaker and topic suggestions to every meeting!
  • Your input for and participation in next year's Forth Day is always welcomed.

Coming to SVFIG - September 26th

Halted / HSC Parking Lot Sale
For a change of pace, SVFIG members are encouraged to attend Halted's annual parking lot sale in Santa Clara. There are always interesting things to see and purchase. The sale begins at 9am. We'll convene for lunch at 11:45 up the street at St. John's Bar and Grill and travel to Stanford for an afternoon of Forth presentations and discussions beginning at 1:30pm

Examples from the Forth Foundation Library - John E. Harbold
John will demonstrate some code which makes use of the Forth equivalent of a C++ Class Library. The Forth Foundation Library (FFL) is a general purpose Forth library. Its main purpose is to make it easier to develop applications. Examples presented will include using the Finite State Machine (FSM) and Dynamic Strings.

Coming to SVFIG on Forth Day 2009

Sam Falvo - "boring details of my website's new blog implementation" - tentative

Coming to SVFIG:

Engineering TV
Fifty engineering topic channels, four new episodes per week.

Botbash 2000 Video
A cheapie video of a May 2000 robot rumble in Mesa, AZ.

Prototyping with QFP Parts - Kevin Appert
This presentation will be based on an article in the September 2008 issue of Circuit Cellar entitled "Prototyping with QFP Parts".

WAV File and Soundcard I/O Software Using Win32Forth - Andy Korsak
This software was written for amateur radio applications. Andy has suggested that it might be useful to look at his code in advance of his talk. Contributions to this work-in-progress would be welcomed. You can download and view his sound card software on the Win32Forth group (membership required), or here.

Solicitations for presentations and assistance:

Mitch Bradley's Forth in C
A volunteer is needed to present and demonstrate this software.

PowerMOPS Demo
Looking for a volunteer to present this.

Kevin Appert: "I've sent an email to the implementer of the PACE FIG-Forth and he responded. I think he got the idea that my invitation to present was 'one-time' rather than 'any time'. Hopefully when there is something else PACE-related on the program, he'll join us and present."

Meet the Mac - Kevin Appert
Kevin Appert: "I'm having trouble emailing Ward McFarland, the Carbon MacForth guy. If anybody knows a good way to buy a copy, fill me in! The email doesn't bounce but it doesn't get answered. The phone number is out of service but the website is still up. I'm also getting error boxes when I try to start PowerMops under OS-9.1, so if anybody wants to help out there I'd be grateful."

Please register your interest for these topics:

If you have anything you'd like to talk about for the August meeting,
please contact Kevin Appert.

Meeting Notes