David, Thanks again for your suggestion. It seems Garmin 18X USB can be tailored to only output certain messages as you said. Hopefully this will improve the performance. I am going to give it a try.
To all others: I am only trying to find the best solution given my other constraints. Will try in the future to go with a system that can take advantage of the 1PPS signal. jack On Mar 10, 2:18 pm, "David J Taylor" <[email protected] this-bit.nor-this.co.uk> wrote: > Unruh wrote: > > [] > > >> The newer "x" version appears to be a lot more sensitive, at the > >> expense of somewhat higher current consumption. You can tell the > >> LVC version what sentences to send. Better check the technical spec > >> to see what the USB one can be told to do: > >> http://www.garmin.com/manuals/GPS18x_TechnicalSpecifications.pdf > > > Unfortnately, the LVC is a serial port output, plus a PPS output. The > > USB > > version has no PPS output and is liable to have pretty bad timing > > (where good=usec). > > .. which is why I suggested checking in the manual as to whether the > output could be set to be a better determined length, which is what the OP > requested. It may be he /has/ to use USB. > > By the way, while timing on USB may not be wonderful, I have an > application receiving some 40GB per day over USB, in fairly small packets > from a DVB satellite feed, and the buffering isn't that great (a few > kilobytes, I believe). Most often it's lossless, but it may be that the > error-correction in the stream-to-file software does a good job! <G> > > Cheers, > David _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
