CR1000 Manual - Campbell Scientific

Section 8. Operation
Using a pull-up resistor on digital I/O channels C1 - C8
8.1.5.3.1 Frequency Resolution
Frequency resolution of a PulseCount() frequency measurement is calculated as
where:
FR = Resolution of the frequency measurement (Hz)
S = Scan Interval of CRBasic Program
Resolution of TimerIO() instruction is:
where:
FR = Frequency resolution of the measurement (Hz)
R = Timing resolution of the TimerIO() measurement =
P = Period of input signal (seconds). For example, P = 1 / 1000 Hz =
0.001 s
E = Number of rising edges per scan or 1, whichever is greater.
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