Question

I comunicate with a serial device via bluetooth.
i send it pid and it responds to me with a data response.
i comunicate with him with serial comunicatione one request-response. i want to measure how many response i receive in one second. i think that i have to know the moment when i do the request and the moment whene i receive the response and do the difference. The result(called delta) is the time-to response of device. in the end i have to do 1000ms/delta.

how can calculate it ?

Answer 1

You can get the before/after time in ms using System.currentTimeMillis() or in nanoseconds using System.nanoTime().

Note:

This method provides nanosecond precision, but not necessarily
nanosecond accuracy

(from the doc)