本文主要介绍ARM JTAG调试的基本原理，基本内容包括了TAP 和BOUNDARY-SCAN ARCHITECTURE的介绍。在此基础上，结合ARM7TDMI详细介绍了JTAG的调试原理。-This paper describes the basic principles of ARM JTAG debugger, the basic elements including TAP and BOUNDARY-SCAN ARCHITECTURE introduction. On this basis, combined with detailed information on ARM7TDMI principles of JTAG debugging.