What is JTAG?

Introduction JTAG, which stands for Joint Test Action Group, is a standard that defines a way to test and debug electronic circuits. It was created in the 1980s as a way to improve the testing and programming of printed circuit boards (PCBs) and has since become an essential tool for electronic design and manufacturing. JTAG allows for the testing and programming of digital and analog circuits, including microprocessors, memory devices, and other digital and mixed-signal components. The standard defines a set of signals that are used to perform various operations on the circuit, such as reading and writing data, controlling the circuit's state, and checking for faults. The JTAG standard is implemented using a set of pins on the circuit, which are used to connect the circuit to a JTAG controller, also known as a JTAG probe. The JTAG controller is typically a specialized piece of hardware or software that is used to communicate with the circuit and perform the desired oper...