JTAG (Joint Test Action Group) is a widely-used interface for testing and debugging embedded systems. Its primary purpose is to provide a standardized way to access internal components of a microcontroller or processor without physically altering the device. JTAG allows developers to perform boundary-scan testing, which helps identify manufacturing defects such as shorts, opens, or misaligned components in a circuit board.

Apart from testing, JTAG is essential for debugging embedded software and hardware interactions. Using a JTAG interface, developers can halt the processor, examine internal registers, modify memory contents, and step through code execution. This is particularly useful for diagnosing issues that cannot be replicated in a simulation environment. JTAG also supports in-system programming, allowing firmware updates directly through the interface.

The significance of JTAG in the embedded world lies in its versatility for both hardware testing and software debugging, making it a vital tool for ensuring reliable performance in embedded applications.

To fully understand the use of JTAG and other essential debugging tools in embedded systems, consider enrolling in an embedded system certification course to deepen your knowledge and hands-on experience.