Hi,
Thanks a lot for your reply, I just want to ask some more questions to clarify things... the PWM is a digital output, right? So as you said, we get a digital input from the echo pin of the HC-SR04 in one digital pin, then we make a PWM output from another digital pin, and finally, we convert this signal into analog pin through a DAC, then we could take this signal back into an analog pin as an analog input into the Arduino, or a PLC... Is that correct?
/MaverickRF