JTAG – Micro-Controller Debugging

The report is a practical guide to identifying and validating JTAG interfaces on embedded hardware (a Linksys BEFSR41 router) using the JTAGulator, covering environment setup, pin discovery (IDCODE and BYPASS scans), and validation steps (BYPASS test) to enable further debugging and analysis. It highlights the security implications of exposed or obscured JTAG Test Access Ports and recommends tools (OpenOCD, GDB, binwalk) and datasheet research for effective hardware-based analysis.