Personal computer flexible multichannel interface for data acquisition of low-frequency signals

The authors describe the structure and give the hardware/software implementation of a multichannel interface card which takes one slot of an IBM PC or compatible computer and enables the PC to perform the data acquisition and storage of signals to be measured. Because of the flexibility of components used in building the card, the user can select, using the keyboard, several operational parameters, such as the sampling rate and number of samples to collect from every channel. Software to control card components is written in assembly language, while that for analyzing collected data is written in a high-level language. Channels work independently, and their combined sampling rate is limited mainly by the speed of the microprocessor used