hi ,thank u both jim and torben ,
but u see i still don't get it???
i mean the ultrasound transmitter has two legs:
one for the square signal and the other is for the ground!! so why in the above code they used both legs for transmitting signal?
and if i remove the loop will the MCU generate 40KHz too?
and how much time does the square wave stay high? and how much time does it stay low??
sorry for the too many questions, but if u help through this point "generating 40KHz square wave" the rest will be just fine. and i'll always be thankfull to u
but u see i still don't get it???
i mean the ultrasound transmitter has two legs:
one for the square signal and the other is for the ground!! so why in the above code they used both legs for transmitting signal?
and if i remove the loop will the MCU generate 40KHz too?
and how much time does the square wave stay high? and how much time does it stay low??
sorry for the too many questions, but if u help through this point "generating 40KHz square wave" the rest will be just fine. and i'll always be thankfull to u