@cts WiPy supports a Pin interrupt, which can be triggered with the rising edge. Look in the documentation for "Pin". And is has a timer module, which could be used for setting the gate time. Look in the documentation at "Timer". However, the precision and speed is very limited. Without testing, I would assume that it works reliably only for frequencies below 1 kHz, with a uncertainty of the gate time of about 1 ms. I