On Wednesday, January 16, 2019 at 6:47:24 PM UTC-5, Graham wrote: > > That really does not make a lot of sense. > I have five BBB's and a few Pocket Beagles, and they all free run within > 50 ppm of where they are supposed to be at 24.000 MHz. > 50 ppm error is about 3.5 seconds per day > You can walk them in closer to 2 ppm(at least at room temperature), by > changing C25 and C26 to 24 pF, rather than the factory supplied 18 pF. > NTPD or timesyncd do not have any problem holding time on my Beagles > within 20 milliseconds or so >
On mine, timesyncd gives up. I get periodic step changes. With the pullups to force 26mHz, it's really accurate even without timesyncd. > I would look at the lid of Y2, the main 24 MHz crystal with a magnifying > glass or microscope. > The frequency is usually laser engraved in the metal lid. > > I'll try that tomorrow. I know that I have at least a half-dozen with this problem, and maybe many more. > Where did you get your Beagle? > > I think these came from Newark. All of them are Rev C from mainstream suppliers - not Seeed, for instance. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/63bd6584-ed8e-48a7-9a64-079149986712%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
