For thoso who want a gentle introduction to what is a JTAG, and how to use a JTAG from Linux to program a Linux device (an iPAQ in the example), here are some links:
http://web.archive.org/web/200410290...de/jtag-howto/
HP iPaq H5450 JTAG HOWTO
http://openwince.sourceforge.net/jtag/
JTAG Tools (Linux)
http://repair4pda.org/handheld_jtag.html
How to Build a JTAG Interface for PDA or Handheld PC
http://openwince.sourceforge.net/jtag/iPAQ-3600/
How to connect the cables on an iPAQ for JTAG flash programming and a sample work session with Linux JTAG Tools
http://axl.freeyellow.com/iPAQ/image...C5-pp2jtag.pdf
Schematics of a simple DIY JTAG adaptor (parallel port to JTAG), supported by Linux JTAG Tools (it seems to be the one used in the previous example).
Now we only have to know if the pins of the JTAG are in the iliad connector or if it's necessary to open the iliad to reach the nedded points.