Jtag-based Systems Programming And Hardware Debugging Research And Applications

JTAG is a important type of debug architectures, which has been registered as one of IC designing specifications named IEEE Std.1149.1. JTAG is playing a important role at the embedded-system development. In the target system without any initialization program, the download of the initialization code to its processor is usually achieved through the in-system program, and the initialization code, such as bootloader, is downloaded through JTAG Due to the advisable design, the methods of using JTAG are extended. When developing embedded-system software, because for the default of software emulation and debug hardware emulation based on JTAG is highlighted. So, the research and application of the in-system program and hardware emulation based on JTAG indicate its important meanings.In this paper, firstly, the architecture and principle of JTAG are introduced in detail that the following works are carried on without it.Secondly, the design of the communication channel between Host and JTAG port is token account. Above all, the software achievements of controlling and running JTAG for some key technology are provided.Third, the in-system program based on JTAG is lied out which is one of the studies in this paper. Perspicuously, the software achievements are still keys.Lastly, the debug architecture about Intel(?)XScale^TMcore is introduced in some degree. In addition, the debug handler which running on the target CPU and the debugger which running on Host are thought better of ,so that they can assort better with each other. When the debugger and debug handler can communicate synchronously by JTAG hardware, accessing CPU registers and dynamically downloading code into instruction Caches are implemented, the hardware debug is achieved.