Quote:
Originally Posted by RoboNerd01
I've been trying to use a hall effect sensor and a magnet to measure pulsed from a spinning wheel. But the cRio seems to not respond fast enough to pick up all the pulses. I started clean, and still the problem remains. Has anyone else had this problem? I need help.
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The problem is that your robot code loop runs a lot slower (20 ms) than your sensor is sending the signal. The FPGA can sample way faster than that (> 10,000 pules per second), and can be accessed by using a counter and calling the counter.getPeriod() method to get the time between pulses.
If you're planning to use this rpm for some type of control loop, you may notice that the reported speed seems to fluctuate. If this happens you can make the FPGA average the last couple of samples to get a better reading.