Counter / Timer cards can be programmed to generate time pulses, measure time periods, count events or measure frequency.
PCI Express Digital I/O Cards with Change-of-State (COS) Detection, IDC50 I/O Connector
USB Digital Counter/Timer Module
USB 32 digital I/O, rugged enclosure and screw terminal connector, Optional Counter/Timers
Multifunction High-Speed USB Digital I/O with 6 Counter Timers