chapter  9
40 Pages

Interfacing Characteristics of digital I/O ports

This chapter aims to introduce readers to the general principles of interfacing sensors and transducers to PC bus I/O cards. We shall describe a variety of common sensors and transducers and, for those who do not wish to make use of ‘off-the-shelf’ signal conditioning modules, details of the circuitry necessary to interface such devices to several commonly available I/O cards has been provided. Before embarking on this task, it is perhaps worth mentioning some of the more important characteristics and limitations of conventional digital and analogue digital I/O ports.