This is raising an interesting point, only vaguely relevant, but we have been testing some software for amateur radio astronomy purposes that controls intruments over serial lines RS-232 or RS-485. Whilst many application run with out problems for days on internal serial cards, we seem unable to find any USB to serial converter that performs anywhere near as well.on our loopback tests. Many of the fail rates suggest that slower speeds give a longer period between errors, but with one well-known converter we could not run at all at 57.6kB. This may not be too much of a problem with GPS control program speeds but it would seem there are few totally reliable products. It may be much more serious for NTP operations.
Of the USB converters the best seemed to use the FTDI chip and driver, but even these have shown fails suggesting the problem is deeper inside the PC. All problems have been on the PC reception leg, causing corruption, and often what seemed like a driver disconnection so the "serial port" became disconnected from the application, and required the app restarting. Alan G3NYK ----- Original Message ----- From: "David VanHorn" <[email protected]> To: "Discussion of precise time and frequency measurement" <[email protected]> Sent: Monday, June 13, 2011 10:46 PM Subject: Re: [time-nuts] Advice on NTP server needed > > ________________________________________ > > > Unfortunately, my D525 mobo doesn't have a serial port and my symetricom > doesn't like the usb converter. One of these days somebody is going to > make a usb coverter that really looks like a serial port. I'm probably > going to buy a serial card for the box if all else fails. > > > > The best serial port boxes I have found, are Edgeports. They are available in 1/2/4/8/16 port versions, and I've picked up the 8 port versions for $50 on ebay. > Dead solid, and reliable. I haven't hit anything that wouldn't work with them. > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
