Hi,
as your Tx and Rx will be on the same side, both facing the object to be detected ...
sound will have a travel equal to ... Twice the distance you look for.
As simple as that !
2 x 10 cm / 340 m/s = ... 0.588 ms = ~ 600 µs
10 cm mini ??? haha ... I let you discover why ... and why to cancel detections under these values ...
Alain
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Why insist on using 32 Bits when you're not even able to deal with the first 8 ones ??? ehhhhhh ...
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IF there is the word "Problem" in your question ...
certainly the answer is " RTFM " or " RTFDataSheet " !!!
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