A-D Matrix LED's and Pulse Width

Not sure if this is expected behavior or not so thought I would bring it up just in case. Feeding Tempi 10ms duty cycle triggers into the A-D Input Matrix, and noticed the 301’s input LED’s do not consistently register Tempi’s input, though the scope picks them up fine. Verified with maths as well.

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This is a known issue listed under the cosmetic bugs section:

http://wiki.orthogonaldevices.com/index.php/ER-301/Tracker#Cosmetic_bugs

Basically, those LEDS are being updated in the graphics thread at around 50Hz, which means they look at the signal once every 20ms. So it is expected that they will often miss short triggers. The solution of course is to low pass filter (cutoff at 25Hz) all of the ABCD inputs before the 50Hz sampling but I’m really not thrilled about throwing an extra 12 low pass filters into the audio thread just for the LED sampling. I must find a better way!

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Ahh that makes sense - thanks for the explanation!