Design Of Lua-based Virtual Instrument Control Framework

The Virtual Instrument(VI) is a combination of traditional instrument and computer technologies. As VI implements many features with software, software debugging is required in the VI development. But the regular debugging methods such as breakpoints are not fitting for the multi-threaded VI software, and the lack of standards also makes the code reuse of VI software debugging difficult. To solve these problems, this dissertation proposed a general solution for the VI software debugging.First of all, this dissertation studied the VI software architecture, and implemented a VI control framework based on technologies such as Lua, command console and component-oriented programming. This framework can be integrated with existing VI software easily, and it provides VI software a convenient IO stream manipulation method, a standard debugging interface, and a scripting based operation method.Secondly, in order to test this framework, this dissertation also implemented an virtual audio oscilloscope as a testing platform. Without the requirement of special hardware module, the oscilloscope uses computer sound card as a data acquiring device, which simplifies the testing platform. Besides, because the architecture of the oscilloscope is simple, it demonstrates the usage of the VI control framework clearly.Finally, this dissertation also studied the usage of Lua and related technologies besides debugging. Using spectrum analyzer as an example, this dissertation proposed a Lua based component-oriented VI software architecture. After dividing VI software into smaller parts, not only each part can be developed and tested separately, but also components with the same functions can be reused in different VI projects.Today, many computer technologies already exist, and how to solve problems with the combination of existing ones is not only a necessary but also an innovation. This dissertation uses Lua in the VI software debugging, and makes a good result.