There is significant jitter using USB for timing. Has been done poorly for a long time. Well known.
Bill Dailey Negativity always wins the short game. But positivity wins the long game. - Gary Vaynerchuk Don’t be easy to understand, Be impossible to misunderstand - Steve Sims > On Nov 5, 2021, at 1:33 PM, Andy Talbot <[email protected]> wrote: > > Use FTDI USB serial ports - you can't go wrong with them. > https://ftdichip.com/ > > I have, at the last count, used something like 200 of their FT232 device in > one form or another on the shack PC. I know that, because device manager > has registered up to COM200. Every time a new one is plugged in, a new COM > port is set up. > > Andy > www.g4jnt.com > > > >> On Fri, 5 Nov 2021 at 18:26, Alec Teal <[email protected]> wrote: >> >> A friend of mine who lives and breaths this stuff (I wont tell you what >> he does - but suffice to say he's authoritative) basically said to me on >> something about serial ports that you can't go wrong with USB stuff, >> even on Linux. >> >> Would that work? >> >> Serial ports certainly are getting scarce! You'd get 2 to a board an >> embarrassingly long time ago! >> >>> On 05/11/2021 06:10, Darren Freeman wrote: >>> On Thu, 2021-11-04 at 22:36 -0700, Rich Wales wrote: >>>> However, mobos with a serial port are becoming harder to find. >>> That's not really been my experience, they just moved it to a header. >>> You will need to supply a DE9 to ribbon cable, say on a bracket, or >>> installed in a cutout elsewhere in the case. >>> >>> This is the first one that I checked, and it has such a port labelled >>> COMA, along the left/bottom edge. >>> https://www.gigabyte.com/Motherboard/B450-AORUS-M-rev-1x/sp#sp >>> >>> Also note that the Linux PPS driver supports the standard PC parallel >>> port, which you can usually find as a header. If you are having >>> performance issues with one, try the other. (But you may need to supply >>> negative-going edges to the parallel port.) >>> >>> >>> Have fun, >>> Darren >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] -- To unsubscribe >> send an email to [email protected] >>> To unsubscribe, go to and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- [email protected] -- To unsubscribe send >> an email to [email protected] >> To unsubscribe, go to and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
