The present invention relates to process I/O controllers for semiconductor
manufacturing to which a tool host can delegate data collection,
monitoring and control tasks. In particular, it relates to process I/O
controllers that can perform more than one of data collection,
monitoring, control and response to commands from a tool host with
statistically repeatable performance and precision. Embodiments described
use prioritized real time operating systems to control of semiconductor
manufacturing tools and data collection from tool associated with the
sensors. Statistically repeatable responsiveness to selected commands and
to sensor inputs during selected recipe steps effectively reduces jitter.