Interrupt-less servo motor controls of pneumatic pumps

The predictability of system behavior based on interrupts, although commonly used in practice, is difficult to analyze because this behavior may vary depending on the order in which interrupts are detected by the system. Polling, however, consists of periodic tasks and an event polling mechanism. Despite the time delay for obtaining a time stamp of an event in polling, recent advances in microprocessors have led to the development of features that are capable of dealing with such challenges effectively. This paper describes an interrupt-less approach to control the servo motor of a pneumatic pump using a special purpose register to maintain the time stamp of a sensor event. The system can provide enhanced predictability even when all the sensor events are periodically polled. Empirical experiments revealed the proposed approach to be as accurate, when measured in terms of the external output of the system, as the interrupt-driven approach.