JTAG for beginners :)

[dds]

How do I find  JTAG ports if they exist on a particular board? Should i probe points with multimeter or oscilloscope?

Thanks.

[djsb]

You could look for the data sheet for a particular device and look for the connections to the following pins

# TDI (Test Data In)
# TDO (Test Data Out)
# TCK (Test Clock)
# TMS (Test Mode Select)

This should give you a good start.