Would it be possible then For the expansion board gpio pins. To read gradual voltage fluctuations to control pattern speed? ( of course with the proper resistors capacitors) Or even setup three separate speed ranges? Not important for it to be a global thing affecting all patterns the code written into a single pattern is just fine.
Thank you,
Twilight
Yes, you can definitely use the analog input pins on the sensor expansion board to read a voltage divider and then use that value to control pattern speed.
Just remember that the max voltage is 3.3V for that ADV when setting up the voltage divider. A handy little calculator is here.
Thanks! I had an idea of tapping into my cars speed sensor to control the speed of my wheel ring led’s. I realize it won’t correlate exactly with the increase of vehicle speed but, I’m sure if I play around with it enough I can make it look pretty awesome.
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I got some 10kΩ sliders and 24kΩ resistors and according to the calculator on the Pixelblaze Advanced page, it should go up to 0.97, but I only get up to 0.29!
If I add another resistor in parallel with the existing one, the read value goes up to 0.44 which makes sense (50% more). If I use no resistor, the value goes to 0.99ish when I am close to the top, and it seems like the top would be about 1.05 or so. Happily at the bottom I get precisely 0.0!
So … it looks like I don’t need the resistor at all, to get the full 0…1 range. Is this safe for the slider?
The sliders are:
I have GND on wire ‘1’, A0 on ‘2’, and the resistor going to 3.3v on ‘3’. Any theories?
You don’t need another resistor when using 3.3v and the analog inputs on either the sensor board, or a V3 analog pin.
A resistor is needed for v2, as its analog input is limited to 1v max.
The resistors purpose for v2 is to drop the voltage down a bit to the pot to about 1v. If you read 1v on the sensor board or V3, you’d get about 1/3.3 ~= 0.3 on the ADC.
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