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I have 4 pulses to count. They range from one pulse every few seconds, to one source that will pulse about 10 times a second- so none are stunningly fast.

Best option? I've had luck using a gpio pin and python edge detection on a single pulse, but with multiple pulses (even on separate pins) I get too many false-positives.

Is there such thing as a 'raspberry pi-pulse-counting addon board'? Another microchip to count pulses that my pi can then just get the count from? Examples of a pi-only gpio solution with multiple pulses?

  • Maybe you have floating wires somewhere? Are your wires pulled down or up when there are no pulses from anywhere. Does the pulse provide a good voltage, at least 1.5v and rising to 2.2v or falling to 0.8v. As joan said, the GPIO can handle allot faster than that without issues. You may want to use a simple transistor to eliminate allot of problems. – Piotr Kula Aug 13 '15 at 18:17
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You can count multiple pulses per second on the Pi without issue. If you are getting false edges I would suspect dodgy wiring.

Here is a webm video of the Pi capturing pulses from 28 gpios and passing the edge information to piscope for display.

Here is a webm video of 800 Hz PWM being generated on one gpio and magnet sensors on a shaft being read from others.

The above examples are using my pigpio library. With the pulse rates you are talking about any gpio library will do, you could probably use bash!

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