Research And Designing Of Target Monitor In Embedded Software Developing Environment

This paper discusses the implement technology of target monitor in embedded software developing environment. At first, we analyzed the running and debugging environment of GDB and Gdbserver-a suite of the GNU debug tools in embedded software developing environment. We analyzed the source code of GDB and Gdbserver, and introduced the GDB remote communication protocol. The execution flow, communication mechanism, and the specific implement procedure to support the GDB debug function are analyzed more intensive.Targeted at the requirement of our project - the embedded software development environment and tools, this paper thoroughly investigated the implement technology of target monitors, and designed a prototype of target monitor of booting type with debugging functions based on Angel monitor. This target monitor prototype runs on our embedded evaluation mainboard with ARM CPU. The architecture of the target monitor in the design consists of four parts: boot procedure of the target machine, generating debug environment, task management and implement of the debug function.In order to connecting the prototype to GDB and supporting the debug function of the latter, this paper presents using the Angel communication protocol as the communication protocol of the prototype. The proposed communication protocol is hierarchical with three layers ~ data provider layer, channel layer and device layer. It is the protocol that enables the target monitor designed in this paper can successfully integrate GDB into the embedded developing environment, because GDB can communicate with this protocol via GDB Remote Debug Interface.