Understanding JTAG and Other Debug Interfaces
1. JTAG Protocol JTAG (Joint Test Action Group) is an international standard testing protocol (IEEE 1149.1 compatible), primarily used for internal chip testing. Most advanced devices today support the JTAG protocol, such as ARM, DSP, and FPGA devices. The standard JTAG interface consists of 4 lines: TMS, TCK, TDI, and TDO, which correspond to test … Read more