EEVblog #499 - What is JTAG and Boundary Scan?

What is the JTAG interface and Boundary Scanning, how does it work, and what is it useful for?

The XJTAG unit: http://www.xjtag.com/jtag-tools/xjlink-xjlink2-jtag-usb.php

Forum: http://www.eevblog.com/forum/blog/eevblog-499-what-is-jtag-and-boundary-scan/

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