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Re: Best way to measure period between pulses? Counters and FPGA
Quote:
Originally Posted by jhersh
The FPGA interface function is called writeTimerConfig_AverageSize(). Looks like we never exposed that to the WPILib API layer in C++ (and therefore Java). It's exposed in LabVIEW.
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And I was sitting in this discussion wondering how nobody knows that you can configure the hardware averaging. It's a register in the FPGA's counter/encoder timer config register, exposed by the Set Timer functions, and is very useful.
Our 2012 robot (with a 4-line handmade aluminum and gaffers tape disc) averaged 12 samples (three whole rotations) to get a perfect signal with ~2.5rpm minimum step. If I set the graph to autosize I could see the controller oscillate between exactly one step above or below the target speed, when steady state.
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