Sara XXXX wrote:

> hi, i was wondering if anyoone can write me a code for an ultrasonic 
> tape measure. pic16f84  has to creat a 40khz signal and then has to 
> count how long iit will take for the sigal to come back, and must from 
> there calculate its distance and send the data to LCD.
>
> I will pay for anyhelp provided
>
>
I think it might be that you measure the phase shift between the signal 
sent out and the signal received.
Check out this link, http://www.mnsi.net/~boucher/Sonar1.htm

James Burkart

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