Measurement Computing Personal Daq/3000 Series - Manual (Page 53)

A typical acquisition might take 6 readings off of the Personal Daq/3000 as illustrated below. The user
determines the scan rate and the number of scans to take.
Personal Daq/3000 Series, Acquisition of Six Readings per Scan
Note: Digital channels do not take up analog channel scan time.
In general, the output of each channel’s counter is latched at the beginning of each scan period (called the
start-of-scan.) Every time the 3000 Series module receives a start-of-scan signal, the counter values are
latched and are available to the unit.
The Personal Daq clears all counter channels at the beginning of the acquisition. This means that the
values returned during scan period 1 will always be zero. The values returned during scan period 2 reflect
what happened during scan period 1.
The scan period defines the timing resolution for the Personal Daq/3000 Series.
If you need a higher timing resolution, shorten the scan period.
Personal Daq/3000 Series User’s Manual 887894 Counter Input Modes 5-19