Welcome to Joe Pfeiffer's home page!

(photo by Becca Pfeiffer)

• Research Interests
• Personal Interests
• Classwork Stuff
• PalmOS Stuff
• Linux Development
• MML Stuff
• Photo Galleries

My current visual programming language research centers on Altaira and Isaac, rule-based visual languages for reactive control of mobile robots. Altaira uses a tile-based navigation scheme, and is suitable for use in small robots with limited processing power, such as HC11 processors. Isaac uses a more general, geometric navigation scheme, and requires a Unix environment on the robot.

• Visual Languages Meet Reactive Robot Control
• Fuzzy Geometric Reasoning for Autonomous Mobile Robots

Some of my personal interests include acting (see my acting link for some photos of a few of my roles) and rebuilding old cars (my daily driver is a '78 Chrysler Newport). I also like to think of myself as camping, hunting and fishing, building model rockets, and practicing martial arts, but there hasn't been much time for those in a while. I hold a shodan in Sanzyuryu Jiujitsu, though I'm not active. I'm fortunate enough to be married to Heather, and to have two children (Joel and Becca).

• This semester (Spring, 2008)
  • CS 273: Machine Programming and Organization
• Past Semesters
• Old Exam Archives
  • CS 273
  • CS 573
  • CS 574

HC11 Stuff

• 
• Miniboard 2.1ext Parts Identification Guide
• Bringing Up The Miniboard
• ASCII code chart
• CS 273-related software
• Windows resources

Click here to download a simple Emacs lisp program that provides two functions, palm-install-buffer and palm-install-region. Anybody who is actually competent at programming Emacs lisp is welcome to rewrite it properly, and to maintain it. Ideally, other useful functions for transferring things back and forth between the Palm and Emacs could go in here.

Linux Development

vrecord 0.1.0

It seems like all the Linux video recording tools I could find out there did far too much for my needs, so I set out to write a simple, command-line video recorder with sane defaults.

When I finished it, I realized it also provided a really simple example of the use of video4linux, popt, and the automake/autoconf/etc tools. It shows a little bit about how to create ppm files, and also includes a brief tutorial on combining audio and video streams into an mpeg.

Here's a ten second sample video captured using vrecord and arecord (no, the a/v sync isn't perfect...)..

libpdf 0.1.0

libpdf is a library for the generation of PDF files from C programs. It is designed so that other language bindings (specifically C++) should be reasonably straightforward; hopefully, it is reasonably well documented. I've been using it to generate a variety of labels and things for Science Fair, so it's at least been through some alpha testing.

Code39.ttf

A TrueType implementation of the standard 3-of-9 barcode. All the supporting software that went into creating it needs to be packaged up to go along with it... I've got it in here with all my linux-specific stuff, but there's no reason I know of that it wouldn't work with something else. The first link in this paragraph is just the font itself; here's a link to the program I wrote to generate the drawing instructions for the font and some other related files, including directions for recreating the font: code39-0.1.tar.gz

Gdl 0.7.2

Gdl (Gtk Down Loader) is a program to download programs to, and communicate with, the Motorola HC11 microprocessor through a serial port. I've gotten tired of trying to keep up with all the myriad libraries necessary make this a gnome application, so all gnome dependencies have been stripped out. It uses the gtk toolkit.

Some other information regarding the HC11 is available under my classwork section, in the CS273 links.

cpqpen-1.1.3

News flash! Michael Fincham has updated the driver to the 2.6.20 kernel, and established a Google code project for it! See http://code.google.com/p/cpqpen2/. Thanks for taking this over, Michael!

I'm afraid my Concerto has been decommissioned, so I can't really be very helpful any more... I'm leaving my drivers available, just in case somebody out there finds them useful. Note that they were last updated for Linux 2.0, and included some mods to XFree86 3.1.1 to work with the pen driver. We're talking really, really old here, folks. Also, I'm afraid I didn't save any of the Windows drivers that came with it, so I can't be any help to anybody who wants those, either. You are welcome to ask me questions, and if I remember the answer I'll tell you!

The PostScript source for the logo is here.

Shawn Clever has made a 3D version in several sizes, with either white or black backgrounds.

Photo Galleries

These photos were taken with an Olympus D-450Z digital camera. Click on a thumbnail to enter a gallery (some of the gallery captions also have links to web pages for related organizations).

	Production photos from the Las Cruces Community Theatre's production of ``Man of La Mancha,'' June 2000, taken by Joe and Becca Pfeiffer. A few that came out well are at the top level; the sub-galleries labelled ``Roll 1'' through ``Roll 5'' are essentially proofs. Some have been massaged a bit to reduce red-eye; others are raw. Sorry, no captions. There's also a photo of me, taken by larrychandler, which you can get to by clicking here.
	Fellowship of Las Cruces Area Rocket Enthusiasts (FLARE) night launch, October 1999.
Christmas 2001 in Mesilla