Design and Implementation of the Arm JTAG Emulator

ARM processors are widely used in embedded electronic products, especially in communication, industry con- trol, and automatic, has become the major processor in embedded electronic products. Nearly all the high performance emulators are developed by oversea tool providers, which are too expensive to be generally developed by a small or tiny company. Some JTAG emulator with low price can't meet the requirements of large scale software development. This pa- per focuses on the problems mentioned above, provide a solution to design and implement the ARM JTAG emulator after studing ARM EmbeddedICE technology, GDB debugging technology, RSP protocol, μC/OS-II and LwIP and etc. This JTAG emulator is designed based on AT91SAM9260, supporting ARM7 and ARM9 serial processor core and JTAG clock rate programming, with the communication interface including 10/100M auto-adapt Ethernet, USB and RS232.