Re: Serial port latency

[Geir Thomassen]

Problem solved !

The main problem was that I didn't know that the equipment used
DTR as character acknowledge (not RTS/CTS which is common for flow
control). I didn't even bother to look at those lines with the
oscilloscope. Now the software runs fine with negligible latency.

Now the total latency is so low that the low_latency option to
setserial really matters, it reduces the total run time of my
program with 38 %

I don't get any measurable speed improvement by forcing the UART
to be detected as a 8250 or a 16450 though.

I have not tested with HZ=1000.

All in all, my problem is solved, thank you all.

Geir