3.6Frequency Measurement
3.6.1Using Advantech 32-bit DLL Driver
This approach is for a high frequency signal.
Measuring pulse frequency is simple by using the Advantech
3.6.2 Using Direct I/O
This approach is for a high frequency signal.
Figure 3.5: Frequency Measurement
It also takes two counters for frequency measurement. Counter 0 counts the number of incoming standard source clock, while Counter 1 counts the number of incoming unknown signal clock pulses.
Connect the standard clock source to Gate of Counter 0 and set Counter 0 to “Mode D”. The total time period can be measured by Counter 0 through the standard source clock (Multiply the number of incoming pulses by their frequency). Also connect the unknown signal to CLK of Counter 1 and set Counter 1 to “Mode B”, and the frequency of the unknown signal can be calculated by dividing the number of pulses by the total time period.
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