Home

Good software is the key to making a computer-based data acquisition system become useful. The scope of the software includes the operation system of the computer (Windows, Mac, Linux, or Unix), the programming language (C, Basic, or G) for the DAQ board, and any functions provided by the DAQ driver software (vendor dependent).

DAQ programming by nature requires low-level hardware function calls which could be difficult to debug and develop. Fortunately, application software bundled with ample function libraries is available for reducing the burden of code debugging, and they can dramatically shorten lead times for prototype development. For example, LabVIEW^TM application software with graphical programming methodology, by National Instruments^®, is one of the more capable products. It rides on a DAQ driver and provides a user-friendly environment for developing complete instrumentation, acquisition, data analysis, and control applications. The user interface of a LabVIEW program can look just like a control panel of a instrument, and for this reason LabVIEW programs are sometimes called a "vi", or "virtual instrument".

LabVIEW can also call or code-in external programs, e.g. Matlab^TM from Mathworks^®, to enhance its analysis capability. Output from LabVIEW can be in a graphical or spreadsheet format (compatible with Excel^TM from Microsoft^®).

One should always remember that there is no free lunch though, for DAQ application software adds another shell on top of the DAQ driver software. In other words, it will increase the load on the computer CPU, and may thus worsen the performance of DAQ hardware. Moreover, its capabilities can only go as far as the driver software can go. If the DAQ driver of a particular DAQ hardware is poorly written, the DAQ application software can not fix the driver and may not be able to execute all of its advertised functions.