How to Verify a JTAG

The Joint Test Action Group is a standardized testing component that allows you to connect to circuit boards. It is also the official name of Intel's Std 1149.1-1990 IEEE Standard Test Access Port and Boundary-Scan Architecture. It connects your computer's processor to its hardware and gives access to system parameters as well as repairs any bugs. With a magnifying glass and your system's user's manual, you can verify a JTAG by viewing its components and PIN number.

Things You'll Need

• Magnifying glass

Instructions

1. Unplug your computer system and refer to its manual on how to open it in order to view the internal hardware.

2. Locate your system's manual's diagram to identify the Intel microchip.

3. Remove the casing from the microprocessor chip. Place it down so that the interface component is on the left.

4. Verify that the JTAG connector is a 20-pin device. The part on the bottom left is the JTAG.

5. View the JTAG through your magnifying glass. Confirm that it has a data register, test access port controller, signals, instruction register and boundary scan register.

References

• Intel Publication: JTAG 101; Randy Johnson, et al; January 2009
• Intel Publication: Intel 80331/80332 I/O Processors JTAG Support; 2004
• Intel Publication: Intel XScale Microarchitecture; 2000