[time-nuts] thunderbolt for ntpd or gpsd

Chris Kuethe chris.kuethe at gmail.com
Mon Jul 14 17:21:15 EDT 2008

On Sun, Jun 15, 2008 at 2:57 PM, Tim Cwik <timenuts at stnhbr.com> wrote:
> I have discovered the even though cgps does not report position or time
> using the Thunderbolt, the stock gpsd is getting enough timing data to
> update ntp. Gpsd is selected as the sys.peer with a jitter of about .8.
> It looks like the PPS pulse is too narrow to be detected on DCD

as i've now got my thunderbolt i can start adding support for it in
gpsd. wayne knowles did a nice patch which i'm using as the foundation
of my development.

the main issue is auto-detecting parity of the serial line since
trimble couldn't make up their minds about 8N1 or 8O1.

i've noticed two primary complaints (with which i agree) - the PPS
output is too short and positions don't seem to be output by default.
i'm probably going to add an initializer to make the thunderbolt emit
position data and crank up the 1PPS pulse length to something
reasonable - at least 1ms. the change will be purely runtime - i won't
write it to EEPROM. does that seem reasonable?


GDB has a 'break' feature; why doesn't it have 'fix' too?

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