[LinuxPPS] linuxpps 2.6.23-rc2p4-g29fe58f3

[Rodolfo Giometti]

On Thu, Sep 27, 2007 at 06:04:06PM -0700, gnu not unix wrote:
> 
> Hello everyone--
> 
> I've built the linuxpps 2.6.23-rc2p4-g29fe58f3 (is that the
> latest?) and have tried to run the Documentation/pps ppstest

The last LinuxPPS version is "5.0.0-rc2".

> program. It gives me a timeout:
> 
> ./ppstest /dev/pps0
> trying PPS source "/dev/pps0"
> found PPS source "/dev/pps0"
> ok, found 1 source(s), now start fetching data...
> time_pps_fetch() error -1 (Connection timed out)
> time_pps_fetch() error -1 (Connection timed out)
> 
> The kernel dmesg shows this when I get the timeout:
> 
> PPS_GETCAP: source 0
> PPS_GETPARAMS: source 0
> PPS_SETPARAMS: source 0
> PPS_FETCH: source 0
> timeout 3.000000000
> PPS_FETCH: source 0
> timeout 3.000000000
> PPS_FETCH: source 0
> timeout 3.000000000
> 
> However, I can run the shm pps userspace program that
> captures dcd and timestamps it on its own, and it works
> fine. So, my gps is delivering pps and the shm program
> can grab its own timestamp. Oddly enough, the dmesg shows 
> this when I have run the shm program:
> 
> PPS event on source 0 at at 1190940926.51594425
> capture assert seq #438 for source 0
> PPS event on source 0 at at 1190940926.52943355
> capture clear seq #438 for source 0
> PPS event on source 0 at at 1190940927.51596409
> capture assert seq #439 for source 0
> PPS event on source 0 at at 1190940927.52946961
> capture clear seq #439 for source 0

The ppstest program is just a poor little testing program. :)

Maybe your GPS antenna needs special enable sequence throught the
serial line or so to start sending PPS data.

> So I'm a bit confused at this point. I have not yet
> tried to patch ntpd and see if it can grab a
> linuxpps timestamp.

Please, try to do so so we are sure your GPS antenna is correctly
configured.

Ciao,

Rodolfo

-- 

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