When performing a buffered time measurement of a digital signal, the initial sample is often invalid. The following devices
detect such samples and discard them.
Bus-powered M Series USB devices
Parallel digital I/O modules connected to CompactDAQ chassis, CompactDAQ controllers, CompactRIO controllers and CompactRIO Single-Board controllers. Refer to
Digital I/O Considerations for C Series Devices.
NI 661x devices
X Series devices