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vvigilante / comelit-simplebus1

Open implementation of a smart doorphone compatible with the comelit simplebus 1 audio protocol
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Dogital Write #2

Open Gurkenflieger opened 1 year ago

Gurkenflieger commented 1 year ago

Hello, sty for the question but why are you connecting the digital write output transistor Q1 over a capacitor C2 and resistor R1 , minimizing fluctuations? Why not connecting it directly with a resistor to the IO18.

vvigilante commented 1 year ago

Let me open by saying that I don't know exactly what's going on.

I think the capacitor there will prevent the micro from holding the gate down for a long time (e.g. in case of software issues and such). You only need to send pulses on the bus, and my understanding is that the capacitor allows you to do that.

Correct me if all this doesn't make sense to you