process stage

In systems design, the stage which produces the heart of a system where the inputs are dealt with to produce the required outputs. It is often the last stage to be designed, because it can be quite complicated.

For example, the simplest timer would use an input switch to activate a monostable delay, which could operate an audible signal that would sound continually during the timed interval. Keeping the same input and output stages, it is possible to expand the process stage to produce a pulsed sound output which may sound better than a continual tone. The process stage could be extended further still to create a timer that remains silent during the timed interval, but sounds an alert at the end. This would require an additional reset input to silence the sounder, but the idea of simple input and output stages combined with more complex process stages allows a range of different solutions to be produced.